JP3028205B2 - Distributed power system and power conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distributed power supply system such as a photovoltaic power generation system, and a power conditioner suitable for the system. The present invention relates to a distributed power supply system and a power conditioner which detect an isolated operation when the supply of power from a power supply is stopped by an active method of minutely changing the output power and output frequency of the distributed power supply.

[0002]

2. Description of the Related Art In recent years, a distributed power source such as solar power generation and a system power source (commercial power source) are interconnected with a reverse power flow. A system has been developed to be supplied from.

FIG. 9 is a configuration diagram of such a conventional solar power generation system. In FIG. 9, reference numeral 2 denotes a solar cell, 3 denotes a backflow prevention diode for preventing a backflow of the output from the solar cell 2, and 4 denotes The power conditioner 4 includes a backflow prevention diode 7, an inverter circuit 9 for converting DC power into AC power synchronized with the system power supply 8, a control of the inverter circuit 9, and control of the inverter circuit 9 as described later. And a system protection circuit 11 that performs a protection operation such as opening an electromagnetic contactor (MC) 10 by detecting an isolated operation. Reference numeral 12 denotes household equipment, and reference numerals 5, 6, and 13 denote breakers.

[0004] In such a photovoltaic power generation system, at the time of interconnection operation in which the system is connected to the system power supply 8, the breakers 5, 6, 13 and the electromagnetic contactor 10 are closed. The DC power is converted into AC power by the inverter circuit 9 of the power conditioner 4, and the AC power is supplied to the household equipment 12 via the breaker 6, and the surplus power flows back to the grid while the power conditioner If the power cannot be provided by the AC power from
Electric power is supplied from the system power supply 8 via the breaker 13.

[0005] In such a system, when the power supply is stopped on the grid side due to a power outage or the like, it is necessary to prevent reverse charging from the distributed power source to the grid side, so that the power supply from the grid side is required. The independent operation in which the supply is stopped is detected, the operation of the power conditioner 4 is stopped, and the electromagnetic contactor 10 is opened.

[0006] Such a suspension of power supply from the system side,
That is, in order to detect the islanding operation, an active method in which a minute fluctuation is given to the output power or the output frequency of the power conditioner 4 and the minute fluctuation is increased during the islanding operation to detect the islanding operation. There is.

[0007]

However, in the detection of the isolated operation by the active method, a plurality of systems are connected in parallel in order to construct a system capable of supplying a large amount of generated power. In such a case, fluctuations in the output of the power conditioner for detecting the islanding operation may interfere with each other to cancel each other, and in such a case, the islanding detection may be hindered.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to prevent the detection of an isolated operation by an active system when a plurality of systems are operated in parallel. And

[0009]

In order to achieve the above-mentioned object, the present invention is configured as follows.

That is, the power conditioner of the present invention converts DC power into AC power and outputs it.
To perform grid-connected operation with the grid power supply.
Single operation when the power supply from the power supply is stopped,
Power detected by an active method of varying the output
-In the conditioner, the power conditioner
Are connected to the system power supply for parallel operation
Is, based on the synchronization signal, the plus side or
Fluctuate to the minus side, plus
Switching of the fluctuation to the minus side is performed by changing the cycle of the system voltage or
Are synchronized with each other to the frequency .

[0011] The power conditioner of the present invention is a DC power supply.
It converts power into AC power and outputs it.
In addition to performing interconnection operation linked to the power source,
The above-mentioned output is used for the islanding operation when the power supply is stopped.
Power conditioner detected by fluctuating active method
Parallel operation with other inverters in the conditioner
When you do, in relation to the other inverter
With a setting unit for setting as a master unit or a slave unit
In both cases, during the parallel operation, the other power conditioner
And are connected to each other via a synchronization signal line.
Generates a synchronization signal when set as a master unit by the setting unit.
And the other power controller via the synchronization signal line.
While applying the output to the conditioner,
Based on the positive or negative side
Switching the fluctuation to the plus or minus side
The system is synchronized with the cycle or frequency of the
When configured as a slave device from the constant portion, the output, before
Other power conditioners provided through the sync signal line
Or positive based on the synchronization signal from the
Fluctuate to the negative side and increase
Switching the fluctuation to the negative side depends on the cycle of the system voltage or
It synchronizes with the frequency .

Also, the power conditioner of the present invention
DC power is converted into AC power and output,
Performs grid-connected operation with the grid power supply and
The islanding operation when the supply of power from
Power conditioner performed by an active method that fluctuates output
The inverter in parallel with other inverters.
Synchronized with the other inverter when it is turned
Interconnected through a signal line, and
If no synchronization signal is given from the
And the other power conditioner via the synchronization signal line.
As well as the synchronization signal.
The output is fluctuated, and the other
When the synchronization signal from the inverter is given
The output fluctuates in synchronization with the applied synchronization signal.
It is something to make.

Further, the power conditioner of the present invention
Means that no synchronization signal is given from the synchronization signal line
When the synchronization signal is generated, the synchronization signal is generated via the synchronization signal line.
The output while giving it to the other inverter.
On the plus or
Fluctuate to the eggplant side, plus
Switching the fluctuation to the eggplant side depends on the cycle or cycle of the system voltage.
Synchronized with the wave number, and the other
When the synchronization signal from the inverter is given
Converts the output to a
To the plus or minus side, and
Switching of the fluctuation to the positive or negative side
May be synchronized with the cycle or frequency of

[0014] The power conditioner of the present invention comprises:
When the operation is stopped by detecting the independent operation, the operation is stopped.
The signal is sent to another power conditioner via the synchronization signal line.
You may give it to a Shona.

[0015] The power conditioner of the present invention can be used for other power conditioners.
When operating in parallel with the inverter,
Interconnected with the word conditioner and the synchronization signal line.
It will be continued.

The power conditioner of the present invention has the aforementioned
Force fluctuations are fluctuations in power or frequency.

The distributed power supply system of the present invention is a solar cell
And a power conditioner according to the present invention.
Power supply for each of the distributed power supplies.
During parallel operation, the conditioners mutually transmit the synchronization signal lines.
It is connected by the in.

According to the power conditioner of the present invention,
A plurality of the power conditioner, when the parallel operation with interconnection to the system power supply, so varying in synchronization with the output from one another, as in the case where the power conditioner to detect to islanding independently islanding There is no hindrance to detection.

Further, since the outputs of the power conditioners are changed in synchronization with each other based on the synchronization signal, the changes in the outputs do not interfere with each other, and the isolated operation can be detected reliably.

Further, by setting a power conditioner for outputting a synchronization signal in advance, another power conditioner can synchronize output fluctuations based on the synchronization signal.

Further, when there is no input of the synchronizing signal, each power conditioner generates a synchronizing signal and outputs it to another power conditioner. Therefore, a power conditioner for outputting the synchronizing signal is set in advance. No need.

Further, each power conditioner outputs a stop signal to another power conditioner when the operation is stopped. Therefore, when one of the power conditioners detects the independent operation and stops the operation, the stop signal is output. In response, the other power conditioners can also be stopped immediately.

According to the distributed power supply system of the present invention, when a plurality of the distributed power supply systems are connected to the system power supply and operated in parallel, the outputs fluctuate in synchronization with each other. It is possible to reliably detect the islanding operation without interfering with each other.

[0024]

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

FIG. 1 is a configuration diagram of a photovoltaic power generation system according to one embodiment of the present invention during parallel operation.

This embodiment shows a configuration in which three photovoltaic power generation systems are operated in parallel, for example, in a factory or a school in order to supply a large amount of generated power.

[0027] Each photovoltaic power generation system ₁ 1 to 1 _3, a solar cell 2 ₁ to 2 _3, the solar cell 2 ₁ to 2 ₃ of the output diode for preventing reverse current to prevent backflow of 3 ₁ to 3 _3, power a conditioner ₄₁ to _5, and a breaker 5 ₁ to 5 _{3, 61} through _3, the power conditioner 4 _{1-4 3} includes a preventing diode 7 _{1-7 3} regurgitation, DC the inverter circuit 91 _to 93 for converting power into synchronized AC power and system power source 8
₃ and a system protection circuit 11 _{1 to} 11 ₃ for controlling the inverter circuits 9 _{1 to} 9 ₃ and performing a protection operation such as detecting an isolated operation and opening the electromagnetic contactors 10 ₁ to 10 ₃ as described later. Have. The home device 12 as a load is
It is connected to the system power supply 8 via the breaker 13.

Each of the power conditioners 4 ₁ to 4 ₃ provides a small variation in the output power, the output frequency, etc., as in the prior art, and detects an active change by utilizing the fact that the small variation increases in the isolated operation. It has an islanding detection function based on a dynamic method.

[0029] In this embodiment, in order to output fluctuations of the power conditioner ₄₁ to ₃ for detecting the islanding operation is, so that never leave interfere with the independent operation detecting interfere with each other, the following It is configured as follows.

[0030] In other words, each of the power conditioner 4 ₁ -
4 ₃ is connected to each other by the synchronization signal line 14 to be described later, based on a common synchronization signal, so as to synchronize with each other timing for the minute variation of the output.

In this embodiment, each of the power conditioners 4 ₁ to 4 ₃ has a setting unit (described later) for setting whether to operate as a master unit or a slave unit during parallel operation. In addition, the power conditioner set as the master unit generates a synchronization signal and outputs it to the power conditioners of other slave units, and also changes the output based on the synchronization signal, thereby changing the power set as the slave unit. The conditioner fluctuates the output based on a synchronization signal from the master unit.

[0032] In this embodiment, the power conditioner 4 ₁ is set as the master unit, the power conditioner 4 _2, 4 ₃ will be described as being set as a slave device.

FIG. 2 shows each of the power conditioners 4 ₁ to 4 _3.
FIG. 2 is a diagram showing a synchronization signal circuit for inputting / outputting a synchronization signal of FIG. 1, and portions corresponding to FIG. 1 are denoted by the same reference numerals.

[0034] Each synchronization signal circuit 15 ₁ to 15 _3, the output photo-coupler 18 ₁ consisting of the output light emitting diode 16 ₁ to 16 ₃ and the output phototransistor 17 _{1-17 3}
To 18 _3, and an input photo-coupler 21 ₁ to 21 ₃ and an input light emitting diode 19 _{1-19 3} and the input phototransistor 20 ₁ to 20 _3, an input light emitting diode 19 _{1-19 3} And output phototransistor 1
They are connected in series between the 7 _{1-17 3} the power and ground.

The connection portion between the input light emitting diode 19 _{1-19 3} an output phototransistor 17 _{1-17 3} of the power conditioner 41 _{to 3,} are connected to each other via a synchronizing signal line 14 the emitter of the output phototransistor 17 _{1-17 3} are connected to each other through a ground line 22.

The output light emitting diode 16 ₁ to 16 ₃ is controlled by the output of the signal output circuit described later, the output of the input phototransistors 20 ₁ to 20 ₃ is taken into the signal input circuit to be described later.

[0037] In this embodiment, the starting and the power conditioner 4 ₁ of the output light emitting diode 16 ₁ which is the parent machine
Off output for the photo transistor 17 ₁ in response to the conduction -
It is shut off, which allows each inverter 4 ₁
To 4 ₃ of the light emitting diodes 19 ₁ to 19 ₃ is turned on and off for input, the input phototransistor 20 ₁ accordingly
20 ₃ so that the conductive and blocking.

Therefore, each power conditioner 4 ₁
4 to ₃ can synchronize the minute fluctuation of the output for islanding operation detection based on a common synchronization signal.

FIGS. 3A and 3B are signal waveform diagrams of this embodiment. FIG. 3A shows a system voltage, and FIG. 3B shows a synchronizing signal waveform for changing the output to a positive side , ie, an increasing side. FIG. 3C shows a synchronous signal waveform for changing the output to a decreasing side , which is a minus side , and FIG. 4D shows a state in which the synchronous signal line 14 is disconnected or no synchronous signal is output. FIG. 7E is a waveform diagram of a stop signal when the operation is stopped upon detecting the independent operation.

In this embodiment, FIGS.
As shown in (1), a synchronization signal synchronized with the cycle of the system voltage is generated, and the configuration is simplified by synchronizing with the system voltage in this way, but it is not always necessary to synchronize with the system voltage. Also, the pattern of the synchronization signal is not limited to this embodiment, but may be any signal having at least two patterns for varying the output to the plus side and the minus side. For example, when the synchronization signal is at a high level,
The output may be changed to the plus side or the minus side, and the output may be changed to the minus side or the plus side when the synchronization signal is at the low level.

[0041] FIG. 4, the power of Figure 1 conditioner 4 ₁
FIG. 4 is a block diagram representatively showing one of 〜 to ₃ , and portions corresponding to FIGS. 1 and 2 are denoted by the same reference numerals.

Each of the power conditioners 4 ₁ to 4
₃ is a same configuration, in FIG. 4, it is representatively shown power conditioner 4 _1.

The system protection circuit 11 ₁ includes a measuring circuit 23 for measuring the system voltage and system frequency, on the basis of the output and the synchronizing signal of the measuring circuit 23, the CPU24 outputs a power generation amount control signal, the output of the CPU24 based on, the output control circuit 25 for controlling the inverter circuit 9 _1, a synchronization signal circuit 15 ₁ described above, the signal output circuit 26 which outputs a signal to the synchronization signal circuit 15 _1, the synchronization signal circuit 1
Signal and the signal input circuit 27 to capture from 5 _1, and a setting unit 28 for setting a master unit or a slave unit.

When the setting unit 28 sets the master unit, the CPU 24 generates a synchronization signal shown in FIGS. 3A and 3B synchronized with the system voltage based on the output of the measurement circuit 23. Then, the output signal is output to the power conditioner of the slave unit via the output photocoupler 18 ₁ of the synchronization signal circuit 15 _{1, and} the synchronization signal is captured via the input photocoupler 21 _1. and controls the inverter circuit 9 ₁ via the output control circuit 25 is minutely vary the output to detect the islanding state.

On the other hand, if it is set as a slave device by setting unit 28, CPU 24 is a synchronization signal from the base unit captures through the input photo-coupler 21 ₁ of the synchronizing signal circuit 15 _1, captured synchronizing signal depending on, and controls the inverter circuit 9 ₁ via the output control circuit 25 is minutely vary the output to detect the islanding state.

[0046] Also, the power conditioner 4 ₁ based on the output of the measuring circuit 23, when it detects the islanding operation in a conventional manner to stop the inverter circuit 9 _1, and opens the electromagnetic contactor 10 _1, further, when it is set as a slave unit, the output light emitting diode 16 ₁ of the output photocoupler 18 _first synchronizing signal circuit 15 ₁ continues always to light, thereby, the other of the power conditioner, FIG. 3 ( outputs a stop signal shown in E), the power conditioner, stops the inverter circuit 9 ₁ in response thereto, thereby opening the electromagnetic contactor 10 _1.

In addition, when set as a master unit,
Isolated operation when it detects the output light emitting diode 16 ₁ of the output photocoupler 18 _first synchronizing signal circuit 15 ₁
, So that the output of the synchronizing signal to other power conditioners is stopped as shown in FIG. 3 (D), and each power conditioner responds thereto, and the inverter circuit 9 ₁ It stops the causes opening the electromagnetic contactor 10 _1.

[0048] Figure 5 is a flow chart illustrating the operation of the power conditioner 4 ₁ set as a master device.

First, the operation is started from a state where the operation is stopped and the output of the synchronization signal is stopped (step n1), and the synchronization signal is output (step n2) to determine whether or not the synchronization signal is input. When there is a synchronization signal input (step n3), the output is changed in synchronization with the synchronization signal to detect the islanding operation by the active system (step n4), and it is determined whether or not the islanding operation is detected. It is determined (step n5), and when islanding is detected,
The operation is stopped, and the output of the synchronization signal is stopped (step n6), and the operation waits until the waiting time until the operation is restarted (step n7).

In step n3, when there is no synchronizing signal, that is, when a stop signal is input or when the synchronizing signal line 14 is disconnected, the process proceeds to step n6.

FIG. 6 is a flowchart for explaining the operation of the power conditioners 4 ₂ and 4 ₃ set as slave units.

First, the operation is started from a state where the operation is stopped (step n10) (step n11), and the operation waits until the synchronization signal input waiting time elapses (step n1).
2) It is determined whether or not there is a synchronization signal input (step n13). If there is a synchronization signal input, the output is changed in synchronization with the synchronization signal to detect the isolated operation by the active system. (Step n14), it is determined whether or not the islanding operation is detected (step n15). When the islanding operation is detected, the operation is stopped, a stop signal is output (step n16), and the master unit again receives the stop signal. The process waits until a synchronization signal is input (step n17).

In step n13, when there is no synchronizing signal, that is, when a stop signal is input, or
When the synchronizing signal line 14 is disconnected, step n1
Move to 6.

[0054] During the parallel operation as described above, the power conditioner 4 _{1-4 3,} based on a common synchronization signal, since changing the output in synchronization with each other, things like output fluctuations cancel each other out Therefore, islanding can be reliably detected.

In addition, any of the power conditioners 4
_{When 1-4 3} detects a single operation, and stops the output of the synchronization signal, or, since outputs a stop signal, other power conditioner, it is possible to stop the operation by receiving it.

Further, the power conditioner functions as a single power conditioner and can be flexibly adapted to the system capacity by connecting a plurality of power conditioners.

In the above embodiment, when the parallel operation is performed, the setting of the master unit or the slave unit is performed in advance, but as another embodiment of the present invention, when the operation is started, When there is no input of a synchronization signal, the mobile terminal itself may output a synchronization signal as a master unit, and when there is an input of a synchronization signal, it may become a slave unit and operate based on the synchronization signal.

FIG. 7 is a flowchart of the determination when the master unit and the slave unit are automatically set in this manner.

First, the operation is started (step n21) from the state where the operation is stopped and the output of the synchronization signal is stopped (step n20), and the operation waits until the waiting time for inputting the synchronization signal elapses (step n22). It is determined whether or not there is a signal input (step n2). If there is no input of a synchronization signal, a synchronization signal is generated as a parent device (step n24), and thereafter, it operates as a parent device.

In step n23, when there is no input of the synchronization signal, the synchronization with the synchronization signal input as the slave is synchronized (step n25), and thereafter, the slave operates.

According to this embodiment, the setting operation of the master unit and the slave unit becomes unnecessary, and in the above-described embodiment, when the master unit is in a state where power cannot be generated, a synchronization signal is output from the master unit. Otherwise, power generation could not be performed even when the slave unit was in a state capable of generating power.In contrast, in this embodiment, the power conditioner that started operation first becomes the master unit, and this disadvantage Absent.

In the above embodiment, when the parallel operation is performed, only the master unit outputs the synchronization signal. However, as another embodiment of the present invention, the master unit and the slave unit are not distinguished. Synchronization signals may be output from all power conditioners.

FIG. 8 is a flowchart in the case of outputting a synchronization signal from all the power conditioners.

First, the operation is started (step n31) from the state where the operation is stopped and the output of the synchronization signal is stopped (step n30), and the operation waits until the input signal waiting time for the synchronization signal elapses (step n32). It is determined whether or not a signal has been input (step n33). If a synchronization signal has been input, a synchronization signal synchronized with the synchronization signal is generated and output (step n34). If there is no input, a synchronization signal is output (step n35), and it is determined again whether or not there is a synchronization signal input (step n36). If there is a synchronization signal input, the output is synchronized with the synchronization signal. The islanding operation is detected by the active method with the fluctuation (step n3).
7) It is determined whether or not the islanding operation is detected (step n38). When the islanding operation is detected, the operation is stopped and the output of the synchronization signal is stopped (step n3).
9) Wait until the waiting time until the restart of operation elapses (step n40).

According to this embodiment, the setting operation of the master unit and the slave unit becomes unnecessary, and in the above-described embodiment, the master unit that outputs the synchronization signal is in a state where power cannot be generated and the synchronization is not performed. When the signal stops, the other slave units also stop generating power. However, in this embodiment, since the other power conditioners also output the synchronization signal, there is no such a problem.

[0066] In the above embodiments, but to detect the islanding operation on all of the power conditioner 4 _{1-4 3,}
Another embodiment of the present invention, carried out in synchronization with only the variation in the output in all of the power conditioner ₄₁ to _3, detection of islanding may be performed only by the base unit 4 _1, Alternatively, the operation may be performed by only one of the slave units 4 ₂ and 4 ₃ .

In the above embodiment, the present invention is applied to the case where three photovoltaic power generation systems are operated in parallel. However, the present invention may be applied to two or four or more photovoltaic power generation systems.

Although the above embodiment has been described by applying the present invention to a solar power generation system using a solar cell as a power source, another embodiment of the present invention uses another power source such as a fuel cell. Of course, the present invention may be applied to a distributed power supply system.

[0069]

As described above, according to the present invention, when a plurality of distributed power supply systems are connected to the system power supply and operated in parallel, the outputs fluctuate in synchronism with each other. As in the case of detecting the islanding operation, the detection of the islanding operation is not hindered.In particular, since the outputs of the power conditioners are changed in synchronization with each other based on the synchronization signal, the output fluctuation is reduced. It is possible to reliably detect the islanding operation without interfering with each other.

Further, by setting a power conditioner for outputting a synchronization signal in advance, another power conditioner can synchronize output fluctuations based on the synchronization signal.

Further, when there is no input of the synchronizing signal, each power conditioner generates a synchronizing signal and outputs the synchronizing signal to another power conditioner. Therefore, a power conditioner for outputting the synchronizing signal is set in advance. No need. Further, when a synchronization signal is input, a synchronization signal synchronized with the synchronization signal is generated and output to another power conditioner, so that the synchronization signal continues to be output even if one of the power conditioners stops operating. Therefore, other power conditioners can continue to operate.

Further, since each power conditioner outputs a stop signal to the other power conditioners when the operation is stopped, when any of the power conditioners detects the independent operation and stops the operation, the stop signal is output. In response, the other power conditioners can also be stopped immediately.

According to the power conditioner of the present invention,
When a plurality of the power conditioners are connected in parallel to the system power supply and operated in parallel, the outputs are changed in synchronization with each other, so that the output changes do not interfere with each other and the isolated operation can be reliably detected. Become.

The power conditioner functions as a single power conditioner and can be flexibly adapted to the system capacity by connecting a plurality of power conditioners.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a parallel operation according to one embodiment of the present invention.

FIG. 2 is a diagram showing a circuit for inputting and outputting a synchronization signal of the power conditioner of FIG. 1;

FIG. 3 is a signal waveform diagram for explaining the operation of the power conditioner of FIG. 1;

FIG. 4 is a block diagram showing the inside of the power conditioner of FIG. 1;

FIG. 5 is a flowchart for explaining the operation of the master unit.

FIG. 6 is a flowchart for explaining the operation of the slave unit.

FIG. 7 is a flowchart of automatic setting of a parent device and a child device.

FIG. 8 is a flowchart of another embodiment of the present invention.

FIG. 9 is a configuration diagram of a conventional example.

[Explanation of symbols]

2,2 _{1 to} 2 ₃ solar cell 4,4 ₁ to 4 ₃ power conditioner 8 system power supply 9,9 _{1 to} 9 ₃ inverter circuit 14 synchronization signal line

Continuation of front page (56) References JP-A-4-229024 (JP, A) JP-A-62-171428 (JP, A) JP-A-7-95059 (JP, A) JP-A-10-4687 (JP, A) , A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02J 3/00-5/00 H02J 7/35 H02M 7/48

Claims (8)

(57) [Claims] 1. A method of converting DC power into AC power and outputting the converted AC power
And when performing the interconnection operation linked to the system power supply
Also, when power supply from the grid power supply is stopped,
German operation is detected by an active method that fluctuates the output.
Power conditioner, a plurality of the power conditioners are connected to the system power supply.
When performing parallel operation in a system, the output is converted to a synchronization signal.
Based on the positive or negative side
Switching the fluctuation to the plus or minus side
Are synchronized with each other with the period or frequency of the grid voltage.
A power conditioner characterized by the following . 2. Converting DC power into AC power and outputting the converted AC power
And when performing the interconnection operation linked to the system power supply
Also, when power supply from the grid power supply is stopped,
German operation is detected by an active method that fluctuates the output.
When the power conditioner is operated in parallel with another power conditioner,
With the master unit or slave unit in relation to other inverters
And a setting unit for setting
During operation, the other inverter and the synchronization signal
Synchronous signal when connected to each other via a line and set as a master unit by the setting unit
To generate the other power via the synchronization signal line.
The output is supplied to the conditioner while
Fluctuate to plus or minus based on the sign
Together with the change to the plus or minus side
The switching is synchronized with the cycle or frequency of the system voltage, and when set as a slave unit by the setting unit, the output is
Other power provided through the synchronization signal line.
Based on the synchronization signal from the conditioner,
Or to the minus side, and to the plus side.
Switching the fluctuation to the negative side
Or a power controller characterized by synchronizing with frequency
Conditioner. 3. Converting DC power into AC power and outputting the converted AC power
And when performing the interconnection operation linked to the system power supply
Also, when power supply from the grid power supply is stopped,
German operation is performed by an active method that fluctuates the output.
When the inverter is operated in parallel with another inverter,
Via the synchronization signal line with other inverters
When they are connected to each other and no synchronization signal is given from the synchronization signal line
Generates a synchronization signal and forwards it through the synchronization signal line.
To the other inverters,
The output is changed in synchronization with the synchronization signal, and the other power conditioner is changed via the synchronization signal line.
When a synchronization signal from
Wherein the output is changed in synchronization with the start signal.
Power conditioner. 4. The power conditioner according to claim 3,
In the case where no synchronization signal is given from the synchronization signal line
Generates a synchronization signal and forwards it through the synchronization signal line.
The above output is applied to other inverters.
On the plus or
Fluctuate to the eggplant side, plus
Switching the fluctuation to the eggplant side depends on the cycle or cycle of the system voltage.
The other power condition is synchronized with the wave number via the synchronization signal line.
When a synchronizing signal is given from the
Positive or minor based on the sync signal provided
To the positive side, plus or minus
Switching the fluctuation to the power side depends on the cycle or frequency of the system voltage.
Power condition characterized by being synchronized with the number
Na. 5. The package according to claim 2, wherein
In the conditioner, when the islanding operation is detected and the operation is stopped,
The signal is sent to another power conditioner via the synchronization signal line.
Power conditioner characterized by giving it to a shocker
Na. 6. The power conditioner according to claim 1,
In parallel operation with other power conditioners,
Synchronous with other inverters via synchronization signal line
Power condition, characterized by being connected to each other
Na. 7. The power according to any one of claims 1 to 6.
-In the conditioner, the output fluctuation is power or frequency fluctuation.
Power conditioner characterized by the following. 8. A solar cell and any one of claims 2 to 7.
Distributed power supply consisting of the power conditioner described in Crab
And each power conditioner of each of the distributed power sources is operated in parallel.
In the case of rotation, these are connected to each other by the synchronization signal line.
And a distributed power supply system.