JP2015136233A - Photovoltaic power generation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photovoltaic power generation system in which the measured value is corrected when the measurement accuracy of the measured value of current is low.SOLUTION: A photovoltaic power generation system includes a solar cell string connecting multiple solar cell modules, a connection box connected with multiple solar cell strings, a current collector for collecting power of the connection box, a plurality of current detectors arranged in the connection box and/or the current collector and detecting the current value of each input unit, and a temperature detector for detecting the temperature of atmosphere where the current detectors are arranged. The current values detected by the current detectors are corrected based on the temperature detected by the temperature detector.

Description

  The present invention relates to a photovoltaic power generation system.

  In recent years, considering the danger of nuclear power generation, it has been studied to reduce the dependence on nuclear power (the ratio of nuclear power generation to the total amount of power generation). On the other hand, it is necessary to secure alternative energy to reduce the dependence on nuclear power plants. However, due to soaring crude oil prices necessary for power generation using thermal power (thermal power generation), which is one of the leading alternative energy sources, and the growing importance of protecting the global environment, it will be possible to generate power using renewable energy such as sunlight. Expectations are growing, and various renewable energy power generation systems are being actively introduced or planned.

  The solar power generation system includes a solar cell string in which a plurality of solar cell modules are connected in series and a current sensor that measures a total output current value of the plurality of solar cell strings. The measured current value is displayed on a display screen or the like. The user or the maintenance manager can determine whether there is an abnormality in the photovoltaic power generation system using the current value displayed on the display screen as a clue.

  By the way, a current sensor is generally provided in a box that collects electric power supplied from a plurality of solar cell strings (see, for example, Patent Document 1).

JP 2011-187807 A

  In the current sensor, the current measurement accuracy varies depending on the temperature (that is, the air temperature) of the atmosphere in which the current sensor is disposed. That is, if the temperature in the box changes from the reference temperature defined in the specification, the current measurement accuracy decreases. When the measurement accuracy of the current measurement value is low, it is not desirable to display the measurement value as it is on the display screen or the like.

  An object of this invention is to provide the solar power generation system which can improve the reliability of the measured value of an electric current in view of said situation.

  In order to achieve the above object, a photovoltaic power generation system according to the present invention includes a solar cell string in which a plurality of solar cell modules are connected, a junction box to which a plurality of the solar cell strings are connected, and power in the junction box. A current collecting device, a plurality of current detectors arranged in the junction box and / or the current collecting device to detect a current value for each input unit, and a temperature of an atmosphere in which the current detector is arranged And a temperature detector for correcting the current value detected by the current detector based on the temperature detected by the temperature detector.

  In the photovoltaic power generation system having the above configuration, the current collector is preferably a current collection box.

  In the photovoltaic power generation system having the above configuration, the current detector preferably uses a Hall element.

  Moreover, in the solar power generation system of the said structure, it is desirable to provide a display part and to display the corrected electric current value on the said display part.

  According to the photovoltaic power generation system of the present invention, it is determined whether correction of the current value detected by the current detector is necessary based on the current state detected by the current detector. Alternatively, according to the photovoltaic power generation system according to the present invention, based on the current state detected by the current detector, the photovoltaic power generation system can use the current value detected by the current detector as a clue in a certain current state range. Take the option of not judging whether there is any abnormality. Therefore, the reliability of determining whether there is an abnormality in the photovoltaic power generation system using the measured value as a clue is improved.

  Moreover, when the incident angle of sunlight to the solar radiation meter is shallow during low solar radiation, the amount of power generated by the solar cell is small and the current value of the current sensor is also small. The smaller the amount of electricity flowing through the current sensor, the larger the detection error and the lower the current measurement accuracy. When the current measurement accuracy is low, the current value is not used to determine whether there is an abnormality in the photovoltaic power generation system. Is preferred.

  As a condition when the measurement accuracy of the current measurement value is low, one of the values of the input voltage, input current, input power, and power generation amount of the power converter output from the current collector and input to the power converter, It is preferable to use any one of the value of the pyranometer, the value of the first thermometer group, and the value of the second thermometer group. Alternatively, when the average value of the current values of the plurality of current sensors or the total generated current is small, the generated power amount of the entire system is determined to be low solar radiation, and the presence or absence of abnormality of the solar power generation system is not determined.

It is a figure which shows schematic structure of the solar energy power generation system which concerns on 1st Embodiment of this invention. It is a figure which shows schematic arrangement | positioning of the solar energy power generation system which concerns on 1st Embodiment of this invention. It is a figure which shows one structural example of a connection box. It is a figure which shows one structural example of a current collection box. It is a figure which shows the example of 1 structure of a power converter device. It is a figure which shows the example of 1 structure of a communication apparatus. It is a figure which shows the example of 1 structure of an abnormality monitoring and control apparatus. It is a figure which shows an example of the data transmission path between a communication apparatus and an abnormality monitoring and control apparatus, and an external server. It is a figure which shows schematic structure of the solar energy power generation system which concerns on 2nd Embodiment of this invention. It is a figure which shows the other structural example of a connection box. It is a figure which shows the other structural example of a power converter device. It is a figure which shows the other structural example of a communication apparatus. It is a figure which shows the other structural example of an abnormality monitoring and control apparatus. It is a figure which shows the other example of the data transmission path between a communication apparatus and an abnormality monitoring and control apparatus, and an external server. It is a figure which shows schematic structure of the solar energy power generation system which concerns on 3rd Embodiment of this invention. It is a figure which shows the further another structural example of a connection box. It is a figure which shows the further another structural example of a power converter device. It is a figure which shows the further another structural example of a communication apparatus. It is a figure which shows the further another structural example of an abnormality monitoring and control apparatus. It is a figure which shows the further another example of the data transmission path between a communication apparatus and an abnormality monitoring and control apparatus, and an external server. It is a figure which shows the required procedure etc. which differ according to the maximum output value of a photovoltaic power generation system. It is a figure which shows the required installation etc. which differ according to the maximum output value of a solar power generation system. It is a flowchart which shows the example of a determination process which a communication apparatus and an abnormality monitoring and control apparatus perform. It is a figure which shows schematic structure of the solar energy power generation system which concerns on 4th Embodiment of this invention. It is a figure which shows the structural example of the connection box which concerns on 4th Embodiment. It is a figure which shows the structural example of the current collection box which concerns on 4th Embodiment. It is a figure which shows the structural example of the power converter device which concerns on 4th Embodiment. It is a figure which shows the structural example of the communication apparatus which concerns on 4th Embodiment. It is a figure which shows the structural example of the abnormality monitoring and control apparatus which concerns on 4th Embodiment. It is a figure which shows the example of the data transmission path between the communication apparatus which concerns on 4th Embodiment, an abnormality monitoring and control apparatus, and an external server.

  Embodiments of the present invention will be described below with reference to the drawings.

<First Embodiment>
FIG. 1A is a diagram showing a schematic configuration of a photovoltaic power generation system according to the first embodiment of the present invention. The photovoltaic power generation system according to the first embodiment of the present invention is a 500 kW class photovoltaic power generation system, and includes 160 solar cell strings 1_ # 1 to 1_ # 160 and 20 junction boxes 2_ # 1 to 1_ # 1. 2_ # 20, four current collection boxes 3_ # 1 to 3_ # 4, two power converters 4_ # 1 to 4_ # 2, a substation facility 5, a pyranometer group 6A and 6B, a first Thermometer groups 7A and 7B, second thermometer groups 7C and 7D, two communication devices 8_ # 1 to 8_ # 2, two signal converters 9_ # 1 to 9_ # 2, 1 And an abnormality monitoring / control device 10 for a stand. In the following description, solar cell strings 1_ # 1 to 1_ # 160 may be referred to as solar cell string 1 when individual division is not necessary. Similarly, in the following description, the connection box 2, the current collection box 3, the power conversion device 4, the communication device 8, and the signal conversion device 9 may be referred to. Moreover, schematic arrangement | positioning of the solar energy power generation system which concerns on 1st Embodiment of this invention is as FIG. 1B.

  Each of the solar cell strings 1_ # 1 to 1_ # 160 has a configuration in which 13 polycrystalline solar cell modules M1 having a maximum output of 240 W are connected in series.

  Each of the connection boxes 2_ # 1 to 2_ # 20 is an 8-circuit input connection box. The junction box 2_ # i collectively outputs the power supplied from the eight solar cell strings 1 _ # (8i-7) to 1_ # 8i (i is a natural number of 20 or less).

  One structural example of the connection box 2 is shown in FIG. In the configuration example shown in FIG. 2, the connection box 2 includes backflow prevention diodes D1 to D8 that prevent current from flowing back to the solar cell string 1 side, a lightning arrester 21 that suppresses a surge voltage during a lightning strike, and an overcurrent. A breaker 22 that opens the electric circuit when it flows is provided.

  The current collection boxes 3_ # 1 to 3_ # 4 are current collection boxes each having five circuits. The current collection box 3_ # j collectively outputs the power supplied from the five connection boxes 2 _ # (5j-4) to 2_ # 5j (j is a natural number of 4 or less). In addition, the current collection box 3 detects an abnormality in input units, that is, in units of eight solar cell strings, and outputs the detection result.

  One structural example of the current collection box 3 is shown in FIG. In the configuration example shown in FIG. 3, the current collection box 3 includes current sensors S1 to S5, a lightning arrester 31 that suppresses a surge voltage during a lightning strike, a breaker 32 that opens an electric circuit when an overcurrent flows, and a communication I / F. And an A / D converter 33 that converts the output signals (analog signals) of the current sensors S1 to S5 into digital signals and outputs the digital signals, and a power supply unit 34. The current sensor S1 of the current collection box 3_ # j has eight measurement values that are necessary to detect an abnormality in units of eight solar cell strings 1_ # (40j-39) to 1_ # (40j-32). The total output current values of the solar cell strings 1 _ # (40j-39) to 1 _ # (40j-32) are acquired, and the acquisition result is output. Further, the current sensor S2 of the current collection box 3_ # j is a measurement value necessary to detect an abnormality in units of eight solar cell strings 1_ # (40j-31) to 1_ # (40j-24). The total output current value of each of the solar cell strings 1 _ # (40j-31) to 1 _ # (40j-24) is acquired, and the acquisition result is output. The same applies to the current sensors S3 to S5 of the current collection box 3_ # j. The power supply unit 34 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V) that serves as a drive voltage for the current sensors S1 to S5 and the A / D converter 33. Voltage, DC24V voltage, etc.) and supply the current sensors S1 to S5 and the A / D converter 33. In addition, although A / D converter 33 and the power supply part 34 may be provided in all the current collection boxes 3, one A / D converter 33 may be shared by several current collection boxes 3, and the same A plurality of current collecting boxes 3 may share one power supply unit 34.

  Although it does not specifically limit as current sensor S1-S5, It is desirable that it is a current detector using Hall elements, such as a Hall sensor and a clamp ammeter. As a result, the current value can be measured without disconnecting the wiring between the junction box 2 and the power converter 4.

  Each of the power conversion devices 4_ # 1 to 4_ # 2 has a maximum output of 240 kW and is a two-circuit input power conversion device. The power conversion device 4_ # k converts DC power, which is the total power of the power supplied from the current collection box 3_ # (2k-1) and the power supplied from the current collection box 3_ # 2k, into AC power. Output (k is a natural number of 2 or less).

  An example of the configuration of the power conversion device 4 is shown in FIG. In the configuration example shown in FIG. 4, the power conversion device 4 converts the DC power received from the two current collection boxes 3 into AC power and outputs the AC power, and the output of the A / D converter 33. A relay 42 that relays signals and transmits them to the communication device 8, a power supply unit 43, and a power sensor S 6 that detects AC power output from the DC / AC inverter 41 are provided. The power supply unit 43 converts a commercial AC voltage (for example, an AC 100 V voltage, an AC 200 V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, a DC 12 V voltage, a DC 24 V voltage, etc.) that serves as a driving voltage for the repeater 42. To supply to the repeater 42. It should be noted that each of the two power conversion devices 4 may be provided with the repeater 42 and the power supply unit 43, but the two power conversion devices 4 may share one repeater 42. One power supply unit 43 may be shared by the power conversion device 4.

  Further, the relay 42 that relays the output signal of the A / D converter 33 and transmits it to the communication device 8 and the power supply unit 43 may be provided in a connection box or a current collection box.

  The substation equipment 5 is a two-circuit input substation equipment. The substation facility 5 boosts the total power of the AC power supplied from the power converter 4_ # 1 and the AC power supplied from the power converter 4_ # 2 to a high voltage (for example, 6600V) or a special high voltage (for example, 72KV). To the power system (not shown).

  The pyranometer group 6A has ten pyranometers, and each of the pyranometer groups 6A is assigned and installed in each of the connection boxes 2_ # 1 to 2_ # 10. The first thermometer group 7A has ten thermometers, and one thermometer (temperature detector) of the second thermometer group 7A is assigned to each of the junction boxes 2_ # 1 to 2_ # 10. Installed.

  Similarly, the pyranometer group 6B has ten pyranometers, and each of the pyranometer groups 6B is assigned and installed in each of the connection boxes 2_ # 11 to 2_ # 20. The first thermometer group 7B has ten thermometers, and each thermometer (temperature detector) of the second thermometer 7B is assigned to each of the junction boxes 2_ # 11 to 2_ # 20. Installed.

  It should be noted that the arrangement of the solarimeter groups 6A and 6B only needs to be able to measure the amount of solar radiation represented by each of the solar cell strings 1, and the number of solarimeters is preferably at least a plurality of the solarimeter groups 6A and 6B. At this time, if the pyranometers are installed at positions where they can be compared with each other, the appropriate calibration time of the pyranometer can be managed and maintenance can be performed with high accuracy. Moreover, depending on arrangement | positioning of the solar cell string 1, you may be comprised by one side of the pyranometer group 6A or 6B.

  The first thermometer groups 7A and 7B are thermometers that measure the temperature of the outside air in which the photovoltaic power generation system is installed, and it is sufficient that the temperature representative of each of the solar cell strings 1 can be measured. The arrangement of the first thermometer groups 7A and 7B only needs to be able to measure the representative temperature of each of the solar cell strings 1, and the number of first thermometers is at least the first thermometer groups 7A and 7B. More than one is preferable. At this time, if the first thermometers are installed at positions where they can be compared with each other, appropriate calibration timing of the first thermometers can be managed and maintenance can be performed with high accuracy. Moreover, depending on arrangement | positioning of the solar cell string 1, you may be comprised by one side of the 1st thermometer group 7A or 7B.

  The first thermometer group 7A or 7B preferably measures the temperature of an arbitrary solar cell module M1. For example, a thermocouple element or the like is attached to the back surface of the solar cell module M1 that does not interfere with power generation. You may measure the back surface temperature of M1.

  The second thermometer groups 7C and 7D are thermometers that measure the temperature of the atmosphere (that is, in the current collection box 3) in which the current sensors S1 to S5 are arranged. As for the arrangement of the second thermometer groups 7C and 7D, it is sufficient that the temperature in the current collection box 3 can be measured, and each second thermometer TH is arranged in each current collection box 3 (see FIG. 3). When the current sensor is arranged in the junction box 2, the arrangement of the second thermometer groups 7C and 7D is in each junction box 2. Further, when the current sensor is arranged in both the connection box 2 and the current collection box 3, the arrangement of the second thermometer groups 7 </ b> C and 7 </ b> D is in each connection box 2 and each current collection box 3. As for the number of second thermometers, it is preferable that the number is equal to or greater than the number of boxes (junction box and / or current collection box) in which current sensors are arranged. At this time, if a plurality of second thermometers are arranged in each box so that they can be compared with each other, appropriate calibration timing of the second thermometer can be managed and maintenance can be performed with high accuracy. In addition, when the location which collects the electric power of a connection box is in the power converter 4, and a current sensor is arranged in each power converter, the arrangement of the second thermometer groups 7C and 7D is the power converter. Within 4. Details of the case where the second thermometer group is arranged in the power conversion device 4 will be described later in the third embodiment.

  In addition, depending on arrangement | positioning of the solar cell string 1, you may be comprised by one side of the 2nd thermometer group 7C or 7D. Further, depending on the arrangement of the junction box 2 and / or the current collection box 3, the second thermometer is not arranged for every box body, and one or two or more box bodies are represented as a representative in the box body. It is good also as arranging a thermometer.

Further, the photovoltaic power generation system of the present embodiment includes a value of any one of input voltage, input current, input power, and power generation amount of the power conversion device that is output from the current collection box and input to the power conversion device. And a calculation unit that calculates the temperature inside the box from at least any two of the values of the first thermometer, and a detection unit that detects the temperature inside the box based on the calculation result by the calculation unit It is good also as having a temperature calculation apparatus which has. According to this configuration, the temperature in the box can be detected by the temperature calculation device without arranging the second thermometer in the box. The temperature calculation device may be provided as a separate configuration, or may be provided in the abnormality monitoring / control device 10, for example.
With respect to the correlation between the above-described data for calculating the internal temperature, a relational expression can be derived in advance by, for example, calculating the heat capacity by solar radiation by solar radiation simulation or the like.
In addition, it is preferable to derive the correlation from data acquired under the condition that the measurement accuracy of the second thermometer is stable. For example, the solar radiation intensity, the outside temperature, the input voltage input to the power converter, the input current, the input Measure the second thermometer for the power, the amount of power generated by the power converter, etc. In addition, the amount of power generated by the solar cell is low and the current value is low when the solar radiation is incident at low sunlight or when the incident angle of the sunlight is shallow. Becomes smaller. As the current is smaller, the detection error of the current sensor is larger, and the measurement accuracy of the current measurement value tends to be lower.
As a condition when the measurement accuracy of the current measurement value is low, one of the values of the input voltage, input current, input power, and power generation amount of the power converter output from the current collection box and input to the power converter, It is preferable to use any one of the value of the pyranometer, the value of the first thermometer, or the value of the second thermometer.

  The communication device 8_ # 1 transmits the digital signal transmitted from the repeater 42 of the power conversion device 4_ # 1 to an external server (not shown in FIG. 1A) via a network according to a predetermined communication protocol. Similarly, the communication device 8_ # 2 transmits the digital signal transmitted from the repeater 42 of the power conversion device 4_ # 2 to an external server (not shown in FIG. 1A) via the network according to a predetermined communication protocol. The communication device 8_ # 1 and the communication device 8_ # 2 may be integrated into a single communication device.

  One configuration example of the communication device 8 is shown in FIG. In the configuration example illustrated in FIG. 5, the communication device 8 includes a communication interface unit that performs communication with the current collection box 3 and the A / D converter in the power conversion device 4 and communication with an external server (not illustrated in FIG. 5). 81, and a control unit 82 that controls data transmission / reception by the communication interface unit 81 and temporarily stores data received by the communication interface unit 81 in an internal temporary memory. A commercial AC voltage (for example, AC 100 V voltage, AC 200 V voltage, etc.) supplied from the outside serves as a drive voltage for the communication interface unit 81 and the control unit 82.

  When the data sent from the A / D converter in the current collection box 3 and the power converter 4 are only data indicating normality, the communication device 8 periodically collects the data and collects the data from an external server (in FIG. 5). (Not shown). On the other hand, when data indicating abnormality is sent from the A / D converter in the current collection box 3 and the power conversion device 4, the communication device 8 immediately transmits the data indicating the abnormality to the external server (FIG. 5). (Not shown).

  Since it is sufficient for the data monitoring by the communication device 8 to be performed while the solar cell string is generating power, the voltage supplied to the control unit 82 and the communication interface unit 81, that is, the power supply voltage of the communication device 8 is set to the commercial AC. Instead of the voltage, the input voltage or output voltage of the power conversion device 4 or the input voltage or output voltage of the power conversion device 4 may be converted. Similarly, the voltage supplied to the power supply unit 34 and the power supply unit 43 is not a commercial AC voltage, but a voltage obtained by converting the input voltage or output voltage of the power conversion device 4 or the input voltage or output voltage of the power conversion device 4. Good.

  The signal conversion device 9_ # 1 digitally outputs the output signal (analog signal) of the pyranometer group 6A, the output signal (analog signal) of the first thermometer group 7A, and the output signal (analog signal) of the second thermometer group 7C. Convert to signal. The signal conversion device 9_ # 1 is desirably installed at a position physically close to the pyranometer group 6A, the first thermometer group 7A, and the second thermometer group 7C. In addition, the signal conversion device 9_ # 2 includes an output signal (analog signal) of the pyranometer group 6B, an output signal (analog signal) of the first thermometer group 7B, and an output signal (analog signal) of the second thermometer group 7D. Is converted to a digital signal. It is desirable to install the signal conversion device 9_ # 2 at a position physically close to the pyranometer group 6B, the first thermometer group 7B, and the second thermometer group 7D. As a result, it is possible to prevent the measurement data from fluctuating due to external noise added to the analog signal.

  In the abnormality monitoring / control device 10, the output signal (analog signal) of the pyranometer group 6A converted into a digital signal, the output signal (analog signal) of the pyranometer group 6B converted into a digital signal, and converted into a digital signal. The output signal (analog signal) of the first thermometer group 7A, the output signal (analog signal) of the first thermometer group 7B converted into a digital signal, and the second thermometer group 7C converted into a digital signal Output signal (analog signal) and the output signal (analog signal) of the second thermometer group 7D converted into a digital signal. Moreover, the abnormality monitoring / control device 10 converts an analog signal into a digital signal among the output signal (analog signal) of the power sensor S6 and the monitoring signal sent from the substation equipment 5. Then, the input digital signal or a digital signal obtained by converting the input analog signal is transmitted to an external server (not shown in FIG. 1A) via a network according to a predetermined communication protocol.

  As monitoring signals sent from the substation equipment 5, for example, a signal indicating the open / close state of the circuit breaker, a signal indicating the state of the transformer, a signal indicating the failure state of the device, a measured value of voltage or current of each part, a wattmeter A signal indicating the measured value can be cited.

  An example of the configuration of the abnormality monitoring / control device 10 is shown in FIG. In the configuration example shown in FIG. 6, the abnormality monitoring / control device 10 controls the communication interface unit 91 that performs communication with an external server (not shown in FIG. 6), the transmission and reception of data by the communication interface unit 91, and the communication I / O A control unit 92 that temporarily stores a digital signal output from F93 in an internal temporary memory, a communication I / F 93, and a power supply unit 94 are provided. The communication I / F 93 includes an A / D converter (not shown), an output signal (analog signal) of the pyranometer group 6A, an output signal (analog signal) of the pyranometer group 6B, and a first thermometer. Group 7A output signal (analog signal), first thermometer group 7B output signal (analog signal), second thermometer group 7C output signal (analog signal), second thermometer group 7D output signal (Analog signal), the output signal (analog signal) of the power sensor S6, and the monitoring signal (analog signal) sent from the substation equipment 5 are converted into digital signals, respectively. The power supply unit 94 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V voltage, DC24V voltage, etc.) to be a driving voltage of the communication I / F 93. Then, it supplies to communication I / F93.

  In addition, since the data monitoring by the abnormality monitoring / control device 10 must be performed even during a period in which the solar cell string is not generating power, the power conversion device can be used without supplying a commercial AC voltage to the power supply voltage of the abnormality monitoring / control device 10. When the input voltage or output voltage of 4 or the input voltage or output voltage of the power conversion device 4 is converted to a converted voltage, delay or restriction occurs in the operation of the abnormality monitoring / control device.

  Here, FIG. 7 shows an example of a data transmission path between the communication device 8 and the abnormality monitoring / control device 10 and the external server.

  In the example shown in FIG. 7, the communication devices 8_ # 1 and 8_ # 2 transmit data to the external server 102 via the mobile phone network or the router 100 and the Internet 101, and the abnormality monitoring / control device 10 transmits data to the external server 102 via the router 100 and the Internet 101.

  Further, the communication devices 8_ # 1 and 8_ # 2 and the abnormality monitoring / control device 10 monitor each other for failure. As a result, the communication devices 8_ # 1 and 8_ # 2 and the abnormality monitoring / control device 10 which are data transmission devices for transmitting monitoring data can be mutually monitored and notified to the device manager, the monitoring device and the external server. . For example, the communication devices 8_ # 1 and 8_ # 2 transmit an inquiry signal to the abnormality monitoring / control device 10 at a predetermined cycle, and the abnormality monitoring / control device 10 transmits a response signal according to the inquiry signal to the communication device. Reply to 8_ # 1 and 8_ # 2. When the communication devices 8_ # 1 and 8_ # 2 receive the response signal from the abnormality monitoring / control device 10, it is determined that the abnormality monitoring / control device 10 has not failed. Conversely, the abnormality monitoring / control device 10 transmits inquiry signals to the communication devices 8_ # 1 and 8_ # 2 in a predetermined cycle, and the communication devices 8_ # 1 and 8_ # 2 respond according to the inquiry signals. A signal is returned to the abnormality monitoring / control device 10. When the abnormality monitoring / control device 10 receives the response signals from the communication devices 8_ # 1 and 8_ # 2, it determines that the communication devices 8_ # 1 and 8_ # 2 are not out of order. As another method, a tester may be inserted into each other's equipment, an internal clock signal may be detected, and a failure determination may be made based on the period / pulse width.

  Note that the communication device 8_ # 1 and the communication device 8_ # 2 may be integrated into a single communication device. The communication device 8 and the abnormality monitoring / control device 10 may be a single device. However, in this case, the power supply of the functional portion corresponding to the communication device 8 and the power supply of the functional portion corresponding to the abnormality monitoring / control device 10 are separated, and even if an abnormality occurs in one power supply, it corresponds to the communication device 8. It is desirable that the functional part to be performed and the functional part corresponding to the abnormality monitoring / control device 10 do not stop simultaneously.

  The abnormality monitoring / control device 10 monitors (determines) whether or not the measurement values measured by the current sensors S1 to S5 are appropriate values. The measured values of the current sensors S1 to S5 are affected by the atmosphere in which the current sensors S1 to S5 are installed, more specifically, the temperature in the current collection box 3. While the solar power generation system is in operation, the temperature in the current collection box 3 is often higher than the reference temperature that determines the specifications of the current sensor, but in that case, the measured value includes an error due to temperature, If the measurement value is displayed on the display screen as it is, a user or administrator who sees the measurement value may determine that there is an abnormality in the solar power generation system.

  Therefore, the measured value of the current measured by the current sensors S1 to S5 is corrected according to the temperature in the current collection box 3, that is, the temperature measured by the second thermometer. The corrected current value is displayed on the display screen. This makes it possible to accurately determine whether there is an abnormality in the solar power generation system.

The method of correcting the measured current value is as follows. In the current sensor, the error due to temperature dependence increases as the difference between the reference temperature for which the specification is determined and the operating temperature increases. The coefficient is, for example, within ± 0.1% / ° C., and if the temperature difference is 30 ° C., the error is within ± 3%. Even if the current sensor is of the same type (same manufacturer, same model), it may not be corrected as a uniform coefficient because it may be + 1%, -2%, or + 3%. In order to correct, it is necessary to grasp the temperature dependence of each current sensor. Since the inspection report from the manufacturer often does not include data measured up to the individual temperature dependence, it is necessary for the manufacturer that assembles the junction box and the current collection box to measure the temperature dependence.
An example of measurement is shown below. A constant current source calibrated in a junction box or a current collecting box incorporating a current sensor is used, and a current is supplied to each current sensor. Put the junction box and current collector box in the thermostatic layer, change their internal temperature, for example, -20 ° C, 0 ° C, 25 ° C, 50 ° C, 70 ° C, and record the current value measured through the current sensor at that time To do. The error can be grasped by comparing the true current value flowing from the constant current source with the current value measured by using a current sensor or the like.
By making this error into a database, if the ambient temperature inside the junction box or the current collector box is known at the time of use at the power generation site, the error at that ambient temperature can be known and the error can be corrected. When the ambient temperature is not in the database, for example, 60 ° C., the values are determined with reference to the values of 50 ° C. and 70 ° C. One method is linear interpolation.

  According to this embodiment, the measured value of the current measured by the current sensor is corrected based on the temperature of the atmosphere in which the current sensor is arranged.

  Further, the measured current value after correction is displayed on the display screen. Therefore, the user and the administrator can grasp an appropriate current measurement value regardless of the atmosphere in which the current sensor is arranged.

  In the photovoltaic power generation system according to the first embodiment of the present invention, by providing five current sensors in one current collection box 3, there are four current collection boxes in the entire photovoltaic power generation system of this embodiment. In this configuration, 20 current sensors are provided in total on the input side of 3, but by providing one current sensor in one connection box 2, there are 20 connection boxes in the entire photovoltaic power generation system of this embodiment. A total of 20 current sensors may be provided on the two output sides. However, the configuration in which the current sensor is provided on the input side of the current collection box 3 can concentrate the installation positions of the current sensors in comparison with the configuration in which the current sensor is provided on the output side of the connection box 2, and the signal line is laid. It is desirable to provide a current sensor on the input side of the current collection box 3 because the maintenance work of the current sensor and the current sensor becomes easy.

  In addition, the specifications of the solar cell module or the number of each component used in the present embodiment is merely an example, and the present invention is limited to the specifications of the solar cell module or the number of each component used in the present embodiment. is not. As another example, 3840 thin film solar cell modules with a maximum output of 130 W are provided, 80 solar cell strings in which thin film solar cell modules with a maximum output of 130 W are connected in 8 series and 3 in parallel are provided, and a connection box with 8 circuit inputs is provided. There can be mentioned a configuration in which 20 units are provided, four 5-circuit input current collection boxes are provided, two power converters having a maximum output of 500 kW and two circuit inputs are provided. In the case of a solar power generation system having this configuration, for example, the system can be installed on a rectangular site having a short side of about 150 m and a long side of about 200 m.

  In the present embodiment, the abnormality monitoring / control device 10 transmits data related to the pyranometer groups 6A and 6, the first thermometer groups 7A and 7B, and the second thermometer groups 7C and 7D. The communication device 8 may transmit data related to the pyranometer groups 6A and 6, the first thermometer groups 7A and 7B, and the second thermometer groups 7C and 7D.

Second Embodiment
FIG. 8 is a diagram showing a schematic configuration of a photovoltaic power generation system according to the second embodiment of the present invention.

  Unlike the photovoltaic power generation system according to the first embodiment of the present invention, the photovoltaic power generation system according to the second embodiment of the present invention has a configuration that does not include a current collection box, and includes 40 solar cell strings 11_. # 1 to 11_ # 40, two junction boxes 12_ # 1 to 12_ # 2, one power conversion device 14, a substation facility 15, a pyranometer group 16, a first thermometer group 17A, The second thermometer group 17 </ b> B, one communication device 18, one signal conversion device 19, and one abnormality monitoring / control device 20 are provided.

  Each of the solar cell strings 11_ # 1 to 1_ # 40 has a configuration in which a plurality of solar cell modules are connected in series. Two adjacent solar cell strings are connected in parallel by a branch cable and then connected to the connection box 2.

  Each of the connection boxes 12_ # 1 to 12_ # 2 is a connection box with 10 circuit inputs. The connection box 12_ # 1 collectively outputs the power supplied from the 20 solar cell strings 11_ # 1 to 11_ # 20. Similarly, the junction box 12_ # 2 collectively outputs the power supplied from the 20 solar cell strings 11_ # 21 to 11_ # 40.

  One structural example of the connection box 12 is shown in FIG. In the configuration example shown in FIG. 9, the connection box 12 suppresses the reverse current prevention diodes D11 to D20 that prevent the current from flowing backward to the solar cell string 11 side, the current sensors S11 to S20, and the surge voltage during lightning strikes. A / D that has a lightning arrester 23, a breaker 24 that opens an electric circuit when an overcurrent flows, and a communication I / F that converts the output signals (analog signals) of the current sensors S11 to S20 into digital signals and outputs them. A converter 25 and a power supply unit 26 are provided. The current sensor S11 of the junction box 12_ # 1 has two solar cell strings 11_ # 1 to 11_ # that are measurement values necessary to detect an abnormality in units of the two solar cell strings 11_ # 1 to 11_ # 2. The total output current value of 2 is acquired, and the acquisition result is output. Further, the current sensor S12 of the junction box 12_ # 2 has two solar cell strings 11_ # 3 which are measurement values necessary for detecting an abnormality in units of the two solar cell strings 11_ # 3 to 11_ # 4). The total output current value of ˜11_ # 4 is acquired, and the acquisition result is output. The same applies to the current sensors S13 to S20 of the connection box 12_ # 1. Further, the connection box 12_ # 2 is also the same as the connection box 12_ # 1 except that the solar cell string number corresponding to each current sensor is changed. The power supply unit 26 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V) that serves as a drive voltage for the current sensors S11 to S20 and the A / D converter 25. Voltage, DC24V voltage, etc.) and supply the current sensors S11 to S20 and the A / D converter 25. The A / D converter 25 and the power supply unit 26 may be provided in each of the two connection boxes 12, but one A / D converter 25 may be shared by the two connection boxes 12. One power supply unit 26 may be shared by two connection boxes 12.

  Although it does not specifically limit as current sensor S11-S20, It is desirable that it is a current detector using Hall elements, such as a Hall sensor and a clamp ammeter. As a result, the current value can be measured without disconnecting the wiring between the junction box 12 and the power converter 14.

  The power converter 14 is a two-circuit input power converter. The power conversion device 14 converts DC power, which is the total power of the power supplied from the connection box 12_ # 1 and the power supplied from the connection box 12_ # 2, into AC power and outputs the AC power.

  One structural example of the power converter 14 is shown in FIG. In the configuration example shown in FIG. 10, the power converter 14 converts the DC power received from the two connection boxes 12 into AC power and outputs the AC power, and the output signal of the A / D converter 25. Is transmitted to the communication device 18, a power supply unit 47, and a power sensor S 7 for detecting AC power output from the DC / AC inverter 45. The power supply unit 47 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V voltage, DC24V voltage, etc.) to be a driving voltage of the repeater 46. To supply to the repeater 46.

  The substation facility 15 is a one-circuit input substation facility. The substation facility 15 boosts the AC power supplied from the power converter 14 to a high voltage (for example, 6600 V) or a special high voltage (7000 V or more, for example, 77 kV) and outputs the boosted power to a power system (not shown).

  The pyranometer group 16 has twenty pyranometers, and each of the pyranometer groups 16 is assigned to each branch cable and installed. The first thermometer group 17A has 20 thermometers, and each thermometer (temperature detector) of the second thermometer group 17A is assigned and installed on each branch cable.

  The first thermometer group 17A is a thermometer that measures the temperature of the outside air in which the photovoltaic power generation system is installed. The first thermometer group 17A preferably measures the temperature of an arbitrary solar cell module M1. For example, a thermocouple element or the like is attached to the back surface of the solar cell module M1 that does not interfere with power generation, and the solar cell module M1. The back surface temperature may be measured.

The second thermometer group 17B is a thermometer that measures the temperature of the atmosphere in which the current sensors S11 to S20 are arranged (that is, in the junction box 12). As for the arrangement of the second thermometer group 17B, it is only necessary to measure the temperature in the junction box 12, and each second thermometer TH is arranged in the junction box 12 (see FIG. 9). As for the number of second thermometers, it is preferable that the number of second thermometers is equal to or greater than the number of junction boxes in which current sensors are arranged. At this time, if a plurality of second thermometers are arranged in each box so that they can be compared with each other, appropriate calibration timing of the second thermometer can be managed and maintenance can be performed with high accuracy.
Further, the second thermometer group 17B may directly measure the temperature of at least one of the current sensors S11 to S20. For example, the temperature may be measured by attaching a thermocouple blocking so as not to hinder the operation of the current sensor.

  Depending on the arrangement of the connection box 12, the second thermometer may be provided in the representative connection box 12 without providing the second thermometer for each connection box 12.

  The communication device 18 transmits the digital signal transmitted from the repeater 46 of the power conversion device 14 to an external server (not shown in FIG. 8) via a network according to a predetermined communication protocol.

  One configuration example of the communication device 18 is shown in FIG. In the configuration example shown in FIG. 11, the communication device 18 communicates with the connection box 12 and the A / D converter in the power converter 14 and communicates with an external server (not shown in FIG. 11). And a control unit 84 that controls transmission / reception of data by the communication interface unit 83 and temporarily stores data received by the communication interface unit 83 in an internal temporary memory. A commercial AC voltage (for example, AC 100 V voltage, AC 200 V voltage, etc.) supplied from the outside serves as a drive voltage for the communication interface unit 83 and the control unit 84.

  When the data sent from the A / D converter in the connection box 12 and the power converter 14 are only data indicating normality, the communication device 18 periodically collects the data and sends it to an external server (not shown in FIG. 11). (Shown). In contrast, when data indicating an abnormality is sent from the A / D converter in the connection box 12 and the power conversion device 14, the communication device 18 immediately transmits the data indicating the abnormality to an external server (in FIG. 11). (Not shown).

  Note that the data monitoring by the communication device 18 is sufficient if it is performed during the period when the solar cell string is generating power. Therefore, the voltage supplied to the control unit 84 and the communication interface unit 83, that is, the power supply voltage of the communication device 18, Instead of the voltage, the input voltage or output voltage of the power converter 14 or the input voltage or output voltage of the power converter 14 may be converted. Similarly, the voltage supplied to the power supply units 26 and 47 may be a voltage obtained by converting the input voltage or output voltage of the power converter 14 or the input voltage or output voltage of the power converter 14 instead of the commercial AC voltage.

  The signal conversion device 19 converts the output signal (analog signal) of the pyrometer group 16, the output signal (analog signal) of the first thermometer group 17 </ b> A, and the output signal (analog signal) of the second thermometer group 17 </ b> B into digital signals. Convert. It is desirable that the signal conversion device 19 be installed at a position physically close to the pyranometer group 16, the first thermometer group 17A, and the second thermometer group 17B. As a result, it is possible to prevent the measurement data from fluctuating due to external noise added to the analog signal.

  The abnormality monitoring / control device 20 includes an output signal (analog signal) of the pyranometer group 16 converted into a digital signal, an output signal (analog signal) of the first thermometer group 17A converted into a digital signal, and a digital signal. The output signal (analog signal) of the second thermometer group 17B converted into is input. Further, the abnormality monitoring / control device 20 converts an analog signal into a digital signal among the output signal (analog signal) of the power sensor S7 and the monitoring signal sent from the substation facility 15. Then, the input digital signal or the digital signal obtained by converting the input analog signal is transmitted to an external server (not shown in FIG. 12) via a network according to a predetermined communication protocol.

  Examples of the monitoring signal sent from the substation facility 15 include a signal indicating the open / close state of the circuit breaker, a signal indicating the state of the transformer, a signal indicating the failure state of the device, a measured value of voltage and current of each part, a wattmeter A signal indicating the measured value can be cited.

  An example of the configuration of the abnormality monitoring / control device 20 is shown in FIG. In the configuration example shown in FIG. 12, the abnormality monitoring / control device 20 controls the communication interface unit 95 that communicates with an external server (not shown in FIG. 12), the transmission and reception of data by the communication interface unit 95, and the communication I / O. A control unit 96 that temporarily stores a digital signal output from F97 in an internal temporary memory, a communication I / F 97, and a power supply unit 98 are provided. The communication I / F 97 includes an A / D converter (not shown), an output signal (analog signal) of the pyranometer group 16, an output signal (analog signal) of the first thermometer group 17A, a second The output signal (analog signal) of the thermometer group 17B, the output signal (analog signal) of the power sensor S7, and the monitoring signal (analog signal) sent from the substation 15 are converted into digital signals, respectively. The power supply unit 98 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V voltage, DC24V voltage, etc.) to be a driving voltage of the communication I / F 97. Then, it supplies to communication I / F97.

  In addition, since the data monitoring by the abnormality monitoring / control device 20 must be performed even during a period in which the solar cell string is not generating power, the power conversion device can be used without using a commercial AC voltage as the power supply voltage of the abnormality monitoring / control device 20. When the input voltage or output voltage of 14 or the input voltage or output voltage of the power conversion device 14 is converted into a converted voltage, delay or restriction occurs in the operation of the abnormality monitoring / control device.

  Here, FIG. 13 shows an example of a data transmission path between the communication device 18 and the abnormality monitoring / control device 20 and the external server.

  In the example shown in FIG. 13, the communication device 18 transmits data to the external server 105 via the mobile phone network or router 103 and the Internet 104, and the abnormality monitoring / control device 20 is connected to the router 103. Data is transmitted to the external server 105 via the Internet 104.

  Further, the communication device 18 and the abnormality monitoring / control device 20 monitor each other for failure. Thereby, it is possible to monitor the communication device 18 and the abnormality monitoring / control device 20 which are data transmission devices that transmit monitoring data. For example, the communication device 18 transmits an inquiry signal to the abnormality monitoring / control device 20 at a predetermined cycle, and the abnormality monitoring / control device 20 returns a response signal to the communication device 18 according to the inquiry signal. When the communication device 18 receives the response signal from the abnormality monitoring / control device 20, it determines that the abnormality monitoring / control device 20 has not failed. Conversely, the abnormality monitoring / control device 20 transmits an inquiry signal to the communication device 18 at a predetermined cycle, and the communication device 18 returns a response signal to the abnormality monitoring / control device 20 in accordance with the inquiry signal. When receiving the response signal from the communication device 18, the abnormality monitoring / control device 20 determines that the communication device 18 has not failed. As another method, a failure may be determined based on the period and the pulse width by inserting an inspection device in each device and detecting an internal clock signal.

  The communication device 18 and the abnormality monitoring / control device 20 may be a single device. However, in this case, the power supply of the functional portion corresponding to the communication device 18 and the power supply of the functional portion corresponding to the abnormality monitoring / control device 20 are separated, and even if an abnormality occurs in one power supply, it corresponds to the communication device 18. The function part to be performed and the function part corresponding to the abnormality monitoring / control device 20 are not stopped simultaneously.

  Moreover, the abnormality monitoring / control device 20 monitors (determines) whether or not the measurement values measured by the current sensors S11 to S20 are appropriate values. Therefore, the measured value of the current measured by the current sensors S11 to S20 is corrected according to the temperature in the junction box 12. The corrected current value is displayed on the display screen. The correction method is the same as in the first embodiment.

  According to the present embodiment, the same effects as those of the first embodiment can be obtained.

<Third Embodiment>
FIG. 14: is a figure which shows schematic structure of the solar energy power generation system which concerns on 3rd Embodiment of this invention.

  Unlike the photovoltaic power generation system according to the first embodiment of the present invention, the photovoltaic power generation system according to the third embodiment of the present invention does not include a current collection box, and has 160 solar cell strings. 121_ # 1 to 121_ # 160, 20 junction boxes 122_ # 1 to 122_ # 20, one power converter 124, substation equipment 125, a pyranometer group 126, and a first thermometer group 127A And a second thermometer group 127B, one communication device 128, one signal converter 129, and one abnormality monitoring / control device 130.

  Each of the solar cell strings 121_ # 1 to 121_ # 160 has a configuration in which a plurality of solar cell modules are connected in series.

  Each of the connection boxes 122_ # 1 to 122_ # 20 is an 8-circuit input connection box. The connection box 122_ # 1 collectively outputs the power supplied from the eight solar cell strings 121_ # 1 to 121_ # 8. Similarly, the junction box 122_ # 2 collectively outputs the electric power supplied from the eight solar cell strings 121_ # 9 to 121_ # 16. The same applies to the connection boxes 122_ # 3 to 122_ # 20.

  One structural example of the connection box 122 is shown in FIG. In the configuration example shown in FIG. 15, the connection box 122 includes backflow prevention diodes D21 to D28 that prevent a current from flowing back to the solar cell string 121 side, a lightning arrester 201 that suppresses a surge voltage during a lightning strike, and an overcurrent. A breaker 202 that opens the electric circuit when it flows is provided. Moreover, as shown in FIG. 15, you may equip the anode side of the backflow prevention diodes D21-D28 with the breakers (disconnectors) B1-B8 for improving safety | security at the time of the maintenance of a solar cell string. .

  The power converter 124 is a 20-circuit input power converter. The power conversion device 124 converts DC power, which is total power supplied from the connection boxes 122_ # 1 to 122_ # 20, into AC power and outputs the AC power.

  One structural example of the power converter 124 is shown in FIG. In the configuration example shown in FIG. 16, the power conversion device 124 converts the DC power received from the 20 connection boxes 122 into AC power and outputs the AC power, the current sensors S21 to S40, and the communication I. A / D converter 204 that converts the output signals (analog signals) of the current sensors S21 to S40 into digital signals and outputs them, the power supply unit 205, and the DC / AC inverter 203. And a power sensor S7 for detecting AC power.

  In addition, the current sensor S21 that measures the amount of current from the junction box 122_ # 1 has eight solar values that are measurement values necessary to detect an abnormality in units of eight solar cell strings 121_ # 1 to 121_ # 8. The total output current values of the battery strings 121_ # 1 to 121_ # 8 are acquired, and the acquisition result is output. Further, the current sensor S22 that measures the amount of current from the junction box 122_ # 2 has eight solar values that are measurement values necessary to detect an abnormality in units of eight solar cell strings 121_ # 9 to 121_ # 16. The total output current values of the battery strings 121_ # 9 to 121_ # 16 are acquired, and the acquisition results are output. The same applies to the current sensors S23 to S40 that measure the amount of current from the connection boxes 122_ # 3 to 122_ # 20. The power supply unit 205 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V) that serves as a drive voltage for the current sensors S21 to S40 and the A / D converter 204. Voltage, DC 24V voltage, etc.) and supply the current sensors S21 to S40 and the A / D converter 204.

  Although it does not specifically limit as current sensor S21-S40, It is desirable that it is a current detector using Hall elements, such as a Hall sensor and a clamp ammeter. As a result, the current value can be measured without disconnecting the wiring between the junction box 122 and the power converter 124. The current sensors S21 to S40, the A / D converter 204, and the like may be configured separately from the power converter 124.

  The substation facility 125 is a one-circuit input substation facility. The substation facility 125 boosts the AC power supplied from the power converter 124 to a high voltage (for example, 6600 V) or a special high voltage (for example, 72 KV) and outputs the boosted voltage to a power system (not shown).

  The pyranometer group 126 has twenty pyranometers, and each of the pyranometers 126 is assigned and installed in each of the connection boxes 122_ # 1 to 122_ # 20. The first thermometer group 127A has 20 thermometers, and each thermometer (temperature detector) of the second thermometer group 127A is assigned to each of the junction boxes 122_ # 1 to 122_ # 20. Installed.

  The first thermometer group 127A is a thermometer that measures the temperature of the outside air in which the photovoltaic power generation system is installed. The first thermometer group 127A preferably measures the temperature of an arbitrary solar cell module M1. For example, a thermocouple element or the like is attached to the back surface of the solar cell module M1 that does not interfere with power generation, and the solar cell module M1. The back surface temperature may be measured.

  The second thermometer group 127B is a thermometer that measures the temperature of the atmosphere (that is, in the power converter 124) in which the current sensors S21 to S40 are arranged. As for the arrangement of the second thermometer group 127B, it is only necessary to measure the temperature in the power converter 124, and each second thermometer TH is arranged in the power converter 124 (see FIG. 16). If a plurality of second thermometers are arranged in the power converter 124 so that they can be compared with each other, appropriate calibration timing of the second thermometer can be managed and maintenance can be performed with high accuracy.

  The communication device 128 transmits the digital signal transmitted from the A / D converter 204 of the power converter 124 to an external server (not shown in FIG. 14) via a network according to a predetermined communication protocol.

  One configuration example of the communication device 128 is shown in FIG. In the configuration example shown in FIG. 17, the communication device 128 communicates with the connection box 122 and the A / D converter in the power converter 124 and communicates with an external server (not shown in FIG. 17). And a control unit 207 that controls transmission / reception of data by the communication interface unit 206 and temporarily stores data received by the communication interface unit 206 in an internal temporary memory. A commercial AC voltage (for example, AC 100 V voltage, AC 200 V voltage, etc.) supplied from the outside serves as a drive voltage for the communication interface unit 206 and the control unit 207.

  When the data sent from the A / D converters in the connection box 122 and the power converter 124 are only data indicating normality, the communication device 128 periodically collects the data and sends it to an external server (not shown in FIG. 17). (Shown). In contrast, when data indicating an abnormality is sent from the A / D converter in the connection box 122 and the power converter 124, the communication device 128 immediately transmits the data indicating the abnormality to an external server (in FIG. 17). (Not shown).

Note that the data monitoring by the communication device 128 is sufficient if it is performed during the period in which the solar cell string is generating power. Therefore, the voltage supplied to the control unit 207 and the communication interface unit 206, that is, the power supply voltage of the communication device 128 is changed to commercial AC. Instead of the voltage, a voltage obtained by converting the input voltage or output voltage of the power converter 124 or the input voltage or output voltage of the power converter 124 may be used. Similarly, the voltage supplied to the power supply unit 205 may be a voltage obtained by converting the input voltage or output voltage of the power converter 124 or the input voltage or output voltage of the power converter 124 instead of the commercial AC voltage.
The signal conversion device 129 converts the output signal (analog signal) of the solar thermometer group 126, the output signal (analog signal) of the first thermometer group 127A, and the output signal (analog signal) of the second thermometer group 127B into digital signals. Convert. It is desirable that the signal conversion device 129 be installed at a position physically close to the pyranometer group 126 and the first and second thermometer groups 127A and 127B. As a result, it is possible to prevent the measurement data from fluctuating due to external noise added to the analog signal.

  In the abnormality monitoring / control device 130, the output signal (analog signal) of the pyranometer group 126 converted into a digital signal, the output signal (analog signal) of the first thermometer group 127A converted into a digital signal, and the digital signal The output signal (analog signal) of the second thermometer group 127B converted into is input. Further, the abnormality monitoring / control device 130 converts the analog signal of the output signal (analog signal) of the power sensor S8 and the monitoring signal sent from the substation equipment 125 into a digital signal. Then, the input digital signal or the digital signal obtained by converting the input analog signal is transmitted to an external server (not shown in FIG. 18) via a network according to a predetermined communication protocol.

  As monitoring signals sent from the substation equipment 125, for example, a signal indicating the open / close state of the circuit breaker, a signal indicating the state of the transformer, a signal indicating the failure state of the device, a measured value of voltage or current of each part, a wattmeter A signal indicating the measured value can be cited.

  A configuration example of the abnormality monitoring / control device 130 is shown in FIG. In the configuration example shown in FIG. 18, the abnormality monitoring / control device 130 controls the communication interface unit 208 that performs communication with an external server (not shown in FIG. 18), the transmission and reception of data by the communication interface unit 208, and the communication I / O. A control unit 209 that temporarily stores a digital signal output from the F210 in an internal temporary memory, a communication I / F 210, and a power supply unit 211 are provided. The communication I / F 210 includes an A / D converter (not shown), an output signal (analog signal) of the pyranometer group 126, an output signal (analog signal) of the first thermometer group 127A, a second The output signal (analog signal) of the thermometer group 127B, the output signal (analog signal) of the power sensor S8, and the monitoring signal (analog signal) sent from the substation equipment 125 are converted into digital signals, respectively. The power supply unit 211 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V voltage, DC24V voltage, etc.) to be a driving voltage of the communication I / F 210. Then, it supplies to communication I / F210.

  In addition, since the data monitoring by the abnormality monitoring / control device 130 must be performed even when the solar cell string is not generating power, the power conversion device can be used without supplying a commercial AC voltage to the power supply voltage of the abnormality monitoring / control device 130. When the input voltage or output voltage of 124 or the input voltage or output voltage of the power converter 124 is converted to a converted voltage, delay or restriction occurs in the operation of the abnormality monitoring / control device.

  Here, FIG. 19 shows an example of a data transmission path between the communication device 128 and the abnormality monitoring / control device 130 and the external server.

  In the example shown in FIG. 19, the communication device 128 transmits data to the external server 108 via the mobile telephone network or router 106 and the Internet 107, and the abnormality monitoring / control device 130 is connected to the router 106. Data is transmitted to the external server 108 via the Internet 107.

  In addition, the communication device 128 and the abnormality monitoring / control device 130 monitor each other for failure. As a result, it is possible to monitor the communication device 128 and the abnormality monitoring / control device 130 which are data transmission devices that transmit monitoring data. For example, the communication device 128 transmits an inquiry signal to the abnormality monitoring / control device 130 at a predetermined cycle, and the abnormality monitoring / control device 130 returns a response signal to the communication device 128 according to the inquiry signal. When the communication device 128 receives the response signal from the abnormality monitoring / control device 130, the communication device 128 determines that the abnormality monitoring / control device 130 has not failed. Conversely, the abnormality monitoring / control device 130 transmits an inquiry signal to the communication device 128 at a predetermined cycle, and the communication device 128 returns a response signal to the abnormality monitoring / control device 130 according to the inquiry signal. When the abnormality monitoring / control device 130 receives the response signal from the communication device 128, it determines that the communication device 128 has not failed. As another method, a failure may be determined based on the period and the pulse width by inserting an inspection device in each device and detecting an internal clock signal.

  The communication device 128 and the abnormality monitoring / control device 130 may be a single device. However, in this case, the power supply of the functional portion corresponding to the communication device 128 and the power supply of the functional portion corresponding to the abnormality monitoring / control device 130 are separated, and even if an abnormality occurs in one power supply, it corresponds to the communication device 128. The function part to be performed and the function part corresponding to the abnormality monitoring / control device 130 are not stopped simultaneously.

  Further, the abnormality monitoring / control device 130 monitors (determines) whether or not the measurement values measured by the current sensors S21 to S40 are appropriate values. Therefore, the measured value of the current measured by the current sensors S21 to S40 is corrected according to the temperature in the power converter 124. The corrected current value is displayed on the display screen. The correction method is the same as in the first embodiment.

  According to the present embodiment, the same effects as those of the first embodiment can be obtained.

<Supplement>
The current collection box 3 of the first embodiment, the power conversion device 14 of the third embodiment of the second embodiment, and the power conversion device 124 of the third embodiment all collect the power of the connection boxes 2, 12, and 122. It is a current collector having a function. As described above, the current sensor is arranged in the junction box and / or the current collector. Therefore, each thermometer of the second thermometer group is arranged in the junction box and / or the current collector. Note that the current collector is not limited to a current collector or a power converter as long as it has a function of collecting the power of the connection boxes 2, 12, and 122.

<Maintenance of solar power generation system>
Although the contents of the purchase system differ from country to country, for example, the interest and expectation of solar power generation system electric power companies are the stable power generation and the stability of the amount of power sold, and a proposal for a mechanism to ensure this is required.

  The photovoltaic power generation system according to the embodiment of the present invention can detect an abnormality in a small unit of the first predetermined number (two or more) of the solar cell strings, so that the solar cell string in which the power generation amount is extremely reduced can be detected for a short time. In this way, it is possible to reach the corresponding part (measurement value acquisition unit), and it is possible for the photovoltaic power generation system power company to receive an accurate and quick maintenance service. Therefore, it is possible to avoid a loss of power sales revenue due to oversight of a decrease in power generation.

  In addition, when the measurement value acquisition unit measures the amount of power generation in the connection box unit, the fault location is identified and the corresponding connection box or current collection box is driven without having to measure and inspect all connection boxes or current collection boxes. This makes it possible to reduce maintenance time. In other words, it is possible to improve the power generation operation rate of the solar power generation system.

  In addition, by constantly monitoring the output characteristics of each junction box, the power path between the module and the power converter is monitored. It becomes possible to reduce. As a result, the burden of maintenance costs on the photovoltaic power system operator is reduced, and the recovery of the investment amount is accelerated.

  In addition, when the measurement value acquisition unit measures the amount of power generated in the connection box unit, repairing and repairing the corresponding part with the lowest output measurement value among the values of the mutual measurement value acquisition unit is the most effective at low cost. Large maintenance service.

  For example, in a photovoltaic power generation system in which solar cell strings composed of 13 series of 240 W modules are input to the connection box in 8 parallels and the output of the power conditioner (hereinafter referred to as power converter) is 250 kW, the output of the connection box is 3. 12 kW × 8 = 24.96 kW, 1 string output 240 W × 13 = 3.12 KW. Assuming that one string breaks down and the output is assumed to be 0 W, when the measured value is acquired in the connection box unit, it is detected as an output drop of 3.12 KW ÷ 24.96 kW = 12.5%. However, when the measured value is acquired in units of power conditioner, it is 3.12kW / 250kW = 1.25%. Taking into account factors such as fluctuations in solar radiation, it is difficult to detect a failure in which one string almost stops generating power.

  In other words, it is possible to reduce oversight of the decrease in the amount of power generation by subdividing the monitoring from the power control unit to the connection box unit. When the measured value acquisition unit measures the amount of power generated by each power converter, for example, assuming that the measurement error of the power converter is ± 5%, if the power selling price is 40 yen / kwh for a 2 MW system Even if there is a loss of about 2,300,000kwh x 40 yen / kwh x 0.05 = 4,600,000 yen per year, there is a possibility of overlooking, but when the measurement value acquisition unit measures the power generation amount of the connection box unit, the measurement error is one string The unit is 0.16% of the total system (640 strings @ 2 MW).

  A 2MW system can avoid overlooking over 2,300,000 kwh x 40 yen / kwh x 0.0016 = 147,200 yen per year.

  In addition, by sending information to the maintenance manager via the Internet connection, etc., the power generation amount measured by the measured value acquisition unit on the connection box basis, it is possible to bring the necessary parts for repairs to the site quickly. become.

  Moreover, even if the linear guarantee of the module power generation output is guaranteed, the power generation company is obliged to find a module whose output has decreased, and thus the linear guarantee of the real module power generation output may not function. On the other hand, measuring the amount of power generated for each module is not practical because it requires an initial cost for installing a measuring device composed of electronic components in units of modules and a cost for maintaining and replacing the measuring device itself. In response to these problems, the photovoltaic power generation system according to the embodiment of the present invention allows the measurement value acquisition unit to measure the amount of power generation in the connection box unit, so that all the connection boxes or current collection boxes are manually operated by maintenance personnel. Even if the measurement inspection is not performed, the failure location of the solar cell string can be specified, so that the maintenance operation cost can be reduced, and the maintenance maintenance based on the linear guarantee of the module power generation output can be handled.

<Fourth embodiment>
FIG. 23 is a diagram showing a schematic configuration of a photovoltaic power generation system according to the fourth embodiment of the present invention.

  Unlike the photovoltaic power generation system according to the first embodiment of the present invention, the photovoltaic power generation system according to the fourth embodiment of the present invention has a configuration that does not include the second thermometer group, and has 80 solar cells. Battery strings 131_ # 1 to 131_ # 80, ten junction boxes 132_ # 1 to 132_ # 10, two current collection boxes 133_ # 1 to 133_ # 2, and two power converters 134_ # 1 to 134_ # 2, substation equipment 135, a pyranometer group 136, a thermometer group 137 (a thermometer group corresponding to the first thermometer group in each of the above embodiments), one communication device 138, and one The signal conversion device 139 and one abnormality monitoring / control device 140 are provided. In addition, the structure according to the solar power generation system which concerns on 1st Embodiment, 2nd Embodiment, and 3rd Embodiment may be sufficient.

  Each of the solar cell strings 131_ # 1 to 131_ # 80 has a configuration in which a plurality of solar cell modules M1 are connected in series.

  Each of the connection boxes 132_ # 1 to 132_ # 10 is an 8-circuit input connection box. The connection box 132_ # 1 collectively outputs the power supplied from the eight solar cell strings 131_ # 1 to 131_ # 8. Similarly, the junction box 132_ # 2 collectively outputs the power supplied from the eight solar cell strings 131_ # 9 to 131_ # 16. The same applies to the connection boxes 132_ # 3 to 132_ # 10.

  One structural example of the connection box 132 is shown in FIG. In the configuration example shown in FIG. 24, the connection box 132 includes backflow prevention diodes D29 to D36 that prevent current from flowing back to the solar cell string 131 side, a lightning arrester 301 that suppresses a surge voltage during a lightning strike, and an overcurrent. A breaker 302 that opens the electric circuit when it flows is provided.

  The current collection boxes 133_ # 1 to 133_ # 2 are current collection boxes with five circuit inputs. The current collection box 133_ # 1 collectively outputs the power supplied from the five connection boxes 122_ # 1 to 122_ # 5. The current collection box 133_ # 2 collectively outputs the power supplied from the five connection boxes 122_ # 6 to 122_ # 10. In addition, the current collection box 133 detects an abnormality in an input unit, that is, in units of eight solar cell strings, and outputs the detection result.

  One structural example of the current collection box 133 is shown in FIG. In the configuration example shown in FIG. 25, the current collection box 133 includes current sensors S41 to S45, a lightning arrester 303 that suppresses a surge voltage during a lightning strike, a breaker 304 that opens a circuit when an overcurrent flows, and a communication I / F. And an A / D converter 305 that converts the output signals (analog signals) of the current sensors S41 to S45 into digital signals and outputs them, and a power supply unit 306. The current sensors S41 of the current collection boxes 133_ # 1 and 133_ # 2 obtain the total output current values of the eight solar cell strings 131, which are measurement values necessary for detecting an abnormality in the eight solar cell strings 131. Then, the acquisition result is output. The current sensors S42 of the current collection boxes 3_ # 1 and 133_ # 2 are the total output current values of the eight solar cell strings 131, which are measurement values necessary for detecting an abnormality in the eight solar cell strings 131. Is acquired and the acquisition result is output. The same applies to the current sensors S43 to S45 of the current collection boxes 133_ # 1 and 133_ # 2. The power supply unit 306 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V) that serves as a drive voltage for the current sensors S41 to S45 and the A / D converter 305. Voltage, DC24V voltage, etc.) and supplied to the current sensors S41 to S45 and the A / D converter 305. In addition, although the A / D converter 305 and the power supply unit 306 may be provided in all the current collection boxes 133, one A / D converter 305 may be shared by a plurality of current collection boxes 133. Alternatively, a plurality of current collection boxes 133 may share one power supply unit 306.

  Although it does not specifically limit as current sensor S41-S45, It is desirable that it is a current detector using Hall elements, such as a Hall sensor and a clamp ammeter. As a result, the current value can be measured without disconnecting the wiring between the junction box 132 and the power converter 134.

  The power converter 134 is a two-circuit input power converter. The power converter 134_ # k converts DC power, which is the total power of the power supplied from the current collection box 133 _ # (2k-1) and the power supplied from the current collection box 133_ # 2k, into AC power. Output (k is a natural number of 2 or less).

  A configuration example of the power converter 134 is shown in FIG. In the configuration example shown in FIG. 26, the power conversion device 134 converts the DC power received from the two current collection boxes 133 into AC power and outputs the AC power, and the output of the A / D converter 305. A relay 308 that relays the signal and transmits it to the communication device 138, a power supply unit 309, and a power sensor S46 that detects AC power output from the DC / AC inverter 307 are provided. The power supply unit 309 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V voltage, DC24V voltage, etc.) to be a driving voltage of the repeater 308. To supply to the repeater 308. Note that the relay unit 308 and the power supply unit 309 may be provided in each of the two power converters 134, but one relay unit 308 may be shared by the two power converters 134. One power supply unit 309 may be shared by the power conversion device 134.

  Further, the relay 308 that relays the output signal of the A / D converter 305 and transmits it to the communication device 138 and the power supply unit 309 may be provided in a connection box or a current collection box.

  The substation equipment 135 is a two-circuit input substation equipment. The substation equipment 135 boosts the total power of the AC power supplied from the power converter 134_ # 1 and the AC power supplied from the power converter 134_ # 2 to a high voltage (for example, 6600 V) or a special high voltage (for example, 72 KV). To the power system (not shown).

  The pyranometer group 136 has ten pyranometers, and each of the pyranometer groups 136 is assigned to each connection box 132 and installed. The thermometer group 137 has ten thermometers (temperature detectors), and each thermometer is assigned and installed in each connection box.

  It should be noted that the arrangement of the pyranometer group 136 only needs to be able to measure the amount of solar radiation represented by each of the solar cell strings 131, and the number of the pyranometers is preferably at least one including the pyranometer group 136. At this time, if the pyranometers are installed at positions where they can be compared with each other, the appropriate calibration time of the pyranometer can be managed and maintenance can be performed with high accuracy.

  The thermometer group 137 is a thermometer that measures the temperature of the outside air in which the photovoltaic power generation system is installed, and in particular, it is only necessary to measure the temperature representative of each of the solar cell strings 131. As for the arrangement of the thermometer group 137, it is sufficient that the temperature representative of each solar cell string 131 can be measured. The number of thermometers is preferably at least one. At this time, if the thermometers are installed at positions where they can be compared with each other, appropriate calibration timing of the thermometers can be managed and maintenance can be performed with high accuracy.

  Moreover, it is preferable that the thermometer group 137 measures the temperature of an arbitrary solar cell module M1, for example, a thermocouple element or the like is attached to the back surface of the solar cell module M1 that does not interfere with power generation, and the back surface temperature of the solar cell module M1 is determined. You can measure.

  The communication device 138 transmits the digital signal transmitted from the repeater 308 of the power converter 134 to an external server (not shown in FIG. 23) via the network according to a predetermined communication protocol.

  One configuration example of the communication device 138 is shown in FIG. In the configuration example shown in FIG. 27, the communication device 138 communicates with the current collection box 133 and the A / D converter in the power converter 134 and communicates with an external server (not shown in FIG. 27). 310 and a control unit 311 that controls transmission / reception of data by the communication interface unit 310 and temporarily stores data received by the communication interface unit 310 in an internal temporary memory. A commercial AC voltage (for example, AC 100 V voltage, AC 200 V voltage, etc.) supplied from the outside serves as a drive voltage for the communication interface unit 310 and the control unit 311.

  When the data sent from the current collection box 133 and the A / D converter in the power converter 134 are only data indicating normality, the communication device 138 periodically collects the data and collects the data from an external server (in FIG. 27). (Not shown). On the other hand, when data indicating abnormality is sent from the current collection box 133 and the A / D converter in the power converter 134, the communication device 138 immediately transmits the data indicating the abnormality to the external server (FIG. 27). (Not shown).

  Note that the data monitoring by the communication device 138 is sufficient if it is performed during the period when the solar cell string is generating power. Therefore, the voltage supplied to the control unit 311 and the communication interface unit 310, that is, the power supply voltage of the communication device 138 is changed to commercial AC. Instead of the voltage, the input voltage or output voltage of the power converter 134 or a voltage obtained by converting the input voltage or output voltage of the power converter 134 may be used. Similarly, the voltage supplied to the power supply units 306 and 309 may be a voltage obtained by converting the input voltage or output voltage of the power converter 134 or the input voltage or output voltage of the power converter 134 instead of the commercial AC voltage.

  The signal converter 139 converts the output signal (analog signal) of the pyranometer group 136 and the output signal (analog signal) of the thermometer group 137 into digital signals. It is desirable that the signal conversion device 139 be installed at a position physically close to the pyranometer group 136 and the thermometer group 137. As a result, it is possible to prevent the measurement data from fluctuating due to external noise added to the analog signal.

  The anomaly monitoring / control device 140 receives an output signal (analog signal) of the pyranometer group 136 converted into a digital signal and an output signal (analog signal) of the thermometer group 137 converted into a digital signal. Moreover, the abnormality monitoring / control device 140 converts an analog signal into a digital signal from the output signal (analog signal) of the power sensor S46 and the monitoring signal sent from the substation equipment 135. Then, the input digital signal or the digital signal obtained by converting the input analog signal is transmitted to an external server (not shown in FIG. 28) via a network according to a predetermined communication protocol.

  As monitoring signals sent from the substation equipment 135, for example, a signal indicating the open / close state of the circuit breaker, a signal indicating the state of the transformer, a signal indicating the failure state of the device, a measured value of voltage or current of each part, a wattmeter A signal indicating the measured value can be cited.

  A configuration example of the abnormality monitoring / control device 140 is shown in FIG. In the configuration example shown in FIG. 28, the abnormality monitoring / control device 140 controls the communication interface unit 312 that communicates with an external server (not shown in FIG. 28), the transmission / reception of data by the communication interface unit 312 and the communication I / A control unit 313 that temporarily stores a digital signal output from the F 314 in an internal temporary memory, a communication I / F 314, and a power supply unit 315 are provided. The communication I / F 314 includes an A / D converter (not shown), an output signal (analog signal) of the pyranometer group 136, an output signal (analog signal) of the thermometer group 137, and an output of the power sensor S47. The signal (analog signal) and the monitoring signal (analog signal) sent from the substation equipment 135 are converted into digital signals, respectively. The power supply unit 315 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V voltage, DC24V voltage, etc.) to be a driving voltage of the communication I / F 314. Then, it supplies to communication I / F314.

  In addition, since the data monitoring by the abnormality monitoring / control device 140 must be performed even during a period when the solar cell string is not generating power, the power supply voltage of the abnormality monitoring / control device 140 is changed to a power conversion device without a commercial AC voltage. When the input voltage or output voltage of 134 or the input voltage or output voltage of the power conversion device 134 is converted to a converted voltage, delay or restriction occurs in the operation of the abnormality monitoring / control device.

  Here, FIG. 29 shows an example of a data transmission path between the communication device 138 and the abnormality monitoring / control device 140 and the external server.

  In the example shown in FIG. 29, the communication device 18 transmits data to the external server 111 via the mobile phone network or router 109 and the Internet 110, and the abnormality monitoring / control device 140 is connected to the router 109. Data is transmitted to the external server 111 via the Internet 110.

  In addition, the communication device 138 and the abnormality monitoring / control device 140 monitor each other for failure. As a result, it is possible to monitor the communication device 138 and the abnormality monitoring / control device 140, which are data transmission devices that transmit monitoring data. For example, the communication device 138 transmits an inquiry signal to the abnormality monitoring / control device 140 at a predetermined cycle, and the abnormality monitoring / control device 140 returns a response signal to the communication device 138 according to the inquiry signal. When the communication device 138 receives the response signal from the abnormality monitoring / control device 140, the communication device 138 determines that the abnormality monitoring / control device 140 has not failed. Conversely, the abnormality monitoring / control device 140 transmits an inquiry signal to the communication device 138 at a predetermined cycle, and the communication device 138 returns a response signal to the abnormality monitoring / control device 140 in accordance with the inquiry signal. When the abnormality monitoring / control device 140 receives the response signal from the communication device 138, the abnormality monitoring / control device 140 determines that the communication device 138 has not failed. As another method, a failure may be determined based on the period and the pulse width by inserting an inspection device in each device and detecting an internal clock signal.

  The communication device 138 and the abnormality monitoring / control device 140 may be a single device. However, in this case, the power supply of the functional part corresponding to the communication device 138 and the power supply of the functional part corresponding to the abnormality monitoring / control device 140 are separated, and even if an abnormality occurs in one power supply, it corresponds to the communication device 138. The functional part corresponding to the malfunction monitoring / control device 140 is prevented from stopping simultaneously.

  The abnormality monitoring / control device 140 monitors (determines) whether or not the measurement values measured by the current sensors S41 to S45 are appropriate values. Therefore, the measured value of the current measured by the current sensors S41 to S46 is corrected according to the temperature in the current collection box 133. The corrected current value is displayed on the display screen. The correction method is the same as in the first embodiment.

According to the present embodiment, the same effects as those of the first embodiment can be obtained.
<Solar power generation system abnormality>

  An example of determining whether there is an abnormality in the photovoltaic power generation system is described below. When the solar radiation intensity is 400 Wh / m2 or more, for example, when the solar radiation intensity at 13:15 on a certain day is 420 h / m2, the output current I # N is assumed to be the output current I # N of the junction box 212_ # N. 1 is 29.92A, output current I # 2 is 29.60A, output current I # 3 is 29.41A, output current I # 4 is 30.92A, output current I # 5 is 30.84A, output current I # 6 is 0.21 A, output current I # 7 is 30.73 A, output current I # 8 is 30.67 A, output current I # 9 is 30.88 A, and output current I # 10 is 30.23 A. At this time, the outside air temperature is 25.5 degrees Celsius, the module back surface temperature is 40 degrees Celsius, the sum of currents of the junction boxes 212_ # 1 to # 10 is 273.41A, the voltage is 375V, and the power converter 214_ # 1 is input to The output of the converter_ # 1 is about 100 kW.

  Instead of the solar radiation intensity, the measurement accuracy of the output current I of the junction box may be determined under the input voltage or input current of the power conversion device or the output power instead of the solar radiation intensity from the correlation between the solar radiation intensity, the outside air temperature, and the power generation amount. .

<Solar power plant>
In Japan, as shown in FIG. 20, the necessary procedures and the purchase price of generated power differ depending on the maximum output value of the photovoltaic power generation system. The smaller the maximum output value, the more the owner of the system. There are many benefits. Therefore, specifications aiming at the upper limit of each category (maximum output value less than 500 kW and as close to 500 kW as possible, maximum output value less than 1 MW and as close as possible to 1 MW, less than 2 MW, and maximum as close as possible to 2 MW) Output value) is preferred. However, since the maximum output of a general power converter is 100 kW or 250 kW, it can be said that the specification in which the maximum output value is set to any one of 400 kW, 900 kW, and 1.9 MW is common. In particular, when the maximum output value is 2 MW or more, an expensive extra high voltage substation equipment is required. For example, in the case of a 1.9 MW solar power generation system and a 2.1 MW solar power generation system, a 1.9 MW solar power generation system However, the capital investment cost can be reduced. That is, the system installation cost and the maintenance cost can be significantly reduced by setting the power generation output to a specific value or less.

  Therefore, in the photovoltaic power generation system according to the present invention, the maximum output value is a predetermined value within a range of 400 kW or more and less than 500 kW, a predetermined value within a range of 900 kW or more and less than 1 MW, and a predetermined value within a range of 1.9 MW or more and less than 2 MW. It is desirable to set any value.

  Further, in Thailand, for example, as shown in FIG. 21, necessary facilities and the like differ depending on the maximum output value of the photovoltaic power generation system, and the smaller the maximum output value, the greater the merit for the system owner. ing. In Japan, the same or similar regulations may be implemented in the future. Therefore, when the maximum output value of the photovoltaic power generation system is classified into a plurality of categories according to laws and regulations, in each category, a predetermined value that is greater than or equal to the value obtained by subtracting 100 kW from the category upper limit threshold and less than the category upper limit threshold In addition, it is desirable to set the maximum output value of the photovoltaic power generation system according to the present invention.

  In the first embodiment described above, the connection box and the current collection box are separate bodies, but the connection box and the current collection box may have an integrated structure.

  Moreover, in embodiment mentioned above, although the power converter device was a structure provided with a DC / AC inverter, when the photovoltaic power generation system which concerns on this invention supplies electric power to a DC power system, a power converter device is It is good to make it the structure provided with the DC / DC converter which converts DC power of a certain voltage value into DC power of a different voltage value, and to make a substation equipment into equipment which raises DC voltage.

  In addition, the above-mentioned “power converter” may be a high-voltage substation or special high-voltage substation required for high-voltage interconnection to the power system, or a charger / discharger that temporarily charges and discharges the generated power to the storage battery. Absent.

  As an example of a power generation unit that generates electric power from renewable energy, a solar power generation system has been described as an example. However, the power generation unit includes an induction generator that generates electric power from the rotational motion of a windmill as a power generation unit. As such, it may be a high-voltage substation or a special high-voltage substation required for high-voltage connection to the power system. Alternatively, a windmill and a speed increaser may be used as a power generation unit, and an induction generator that generates power from rotational motion may be used as a power conversion unit.

  Examples of renewable energy include tidal power generation, geothermal power generation, solar thermal power generation, and the like. A generator that generates electric power from the rotational motion of a turbine may be used as a power generation unit. Alternatively, a generator that generates electric power from the rotational motion of the turbine using the turbine itself as a power generation unit may be used as the power conversion unit.

  In the above-described embodiment, the communication device and the abnormality monitoring / control apparatus transmit the acquired data to the external server as they are. However, the communication device and the abnormality monitoring / control apparatus are normal for at least one of the acquired data as shown in the flowchart of FIG. It may be determined whether or not there is an abnormality, and if it is abnormal, the alarm level may be changed according to the degree of departure from the normal value (notification to the external server). In this case, it is possible to provide a judgment material that serves as a reference when determining what action should be taken when an abnormality occurs to a chief engineer who performs remote monitoring using an external server. Note that “normal value”, “normal value determination coefficient”, “alarm level 1 coefficient” or “alarm level n−1 coefficient” in FIG. 22 are positive values, and “normal value determination coefficient” <“alarm level”. The relationship of “1 coefficient” <“alarm level 2 coefficient” <... <“Alarm level n−1 coefficient” is satisfied. FIG. 22 illustrates the case where the determination target data is data that is larger than the normal range at the time of abnormality. However, when the determination target data is data that is smaller than the normal range at the time of abnormality, each step is performed. You can reverse the inequality sign.

1_ # 1 to 1_ # 160, 11_ # 1 to 11_ # 40, 121_ # 1 to 121_160, 131_ # 1 to 131_80 solar cell strings 2_ # 1 to 2_ # 20, 12_ # 1 to 12_ # 2, 122_ # 1 122_ # 20, 132 # 1-132_ # 10 Junction box 3_ # 1-3_ # 4, 133_ # 1-133_ # 2 Current collection box (current collector)
4_ # 1 to 4_ # 2, 134 Power converter 14, 124 Power converter (current collector)
5, 15, 125, 135 Transformer 6A, 6B, 16, 126, 136 Radiometer group 7A, 7B, 17A, 127A First thermometer group 7C, 7D, 17B, 127B Second thermometer group 137 Thermometer Group 8_ # 1-8_ # 2, 18, 128, 138 Communication device 9_ # 1-9_ # 2, 19, 129, 139 Signal conversion device 10, 20, 130, 140 Abnormality monitoring / control device 21, 31, 23, 201, 301, 303 Lightning arrester 22, 24, 32, 202, 302, 304 Breaker 25, 33, 204, 305 A / D converter 26, 34, 43, 47, 94, 205, 211, 306, 309 Power supply 41 , 45, 203, 307 DC / AC inverter 42, 46, 308 Repeater 81, 83, 91, 95, 206, 208, 310, 312 Over the face portion 82,84,92,96,207,209,311,313 controller 93,97,210,314 communication I / F
B1-B8 breaker (disconnector)
D1-D8, D11-D28, D29-D36 Backflow prevention diodes S1-S5, S11-S40, S41-S45 Current sensors S6-S8, S46 Power sensors

Claims (4)

A solar cell string in which a plurality of solar cell modules are connected;
A junction box to which a plurality of the solar cell strings are connected;
A current collector that collects the power of the junction box;
A plurality of current detectors arranged in the junction box and / or the current collector to detect a current value for each input unit;
A temperature detector for detecting the temperature of the atmosphere in which the current detector is disposed;
With
A photovoltaic power generation system, wherein a current value detected by the current detector is corrected based on a temperature detected by the temperature detector.   The solar power generation system according to claim 1, wherein the current collector is a current collection box.   The solar power generation system according to claim 1 or 2, wherein the current detector uses a Hall element.   The photovoltaic power generation system according to any one of claims 1 to 3, further comprising a display unit, wherein the corrected current value is displayed on the display unit.

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