JP2007327961A - Electric power meter and electric power surveillance system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cheap and precise electric power meter which can survey and control the electric power consumption of an electrical facility via the Internet. <P>SOLUTION: An electric power surveillance system 200 comprises the electric power meter 100 equipped with a sensor module 12 and a communication module 13, a data display which is received from the communication module 13, a client surveillance device 60 equipped with an electric power meter management soft performing a data preservation, or a management of the electric power meter 100. Furthermore, the electric power meter 100 can process a sampling processing and operation processing of voltage and current in the sensor module 12 and a data exchange processing with the sensor module and a network communication processing in the communication module 13 using one microprocessor 60. As a result, a cost of the electric power meter as a whole can be reduced. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a technical field related to an electronic instrument, specifically to a power meter and a power monitoring system. That is, the present invention relates to a network-connected power meter that can simultaneously perform power measurement processing and arithmetic processing and communication processing through a network, and a power monitoring system including such a power meter.

In order to reduce the amount of energy used, it is necessary to accurately and inexpensively measure the amount of electric energy used for each electrical facility or each specific range of a building. A digital power meter using a microprocessor has been proposed as a device for measuring the amount of electric energy used by a terminal load such as an electric facility (Patent Document 1). The digital wattmeter described in Patent Document 1 performs A / D conversion by sampling an input voltage waveform and an input current waveform, and multiplies the digitally converted voltage data and current data to obtain instantaneous power, and a sampling period The average power is obtained, and the integrated power is obtained by time-converting the product sum of the average power. The digital wattmeter can perform digital sampling and power calculation at the same time, has a feature that it is easy to realize a multiple signal system, and is more accurate than a mechanical wattmeter.
JP-A-5-172859

  Since the digital wattmeter described in Patent Document 1 cannot be remotely controlled, it is necessary to go to the site and read the electricity usage status of the electrical equipment. In addition, since the input voltage waveform and the input current waveform are not sampled seamlessly but are sampled for a certain period, an error may occur in the sampling data.

  An object of the present invention is to provide an inexpensive and highly accurate power meter that can monitor and control the amount of electric power used by an electric facility via the Internet.

  The power meter according to the first aspect includes a sensor module, a communication module, and one microprocessor. Here, in the sensor module, the voltage and current of the electrical equipment are sampled, and current data, voltage data, and power data are calculated from the sampled measurement values. On the other hand, the communication module performs data exchange with the sensor module and network communication processing by the TCP / IP protocol. Among them, sampling processing and calculation processing of voltage and current in the sensor module, data exchange with the sensor module in the communication module, and network communication processing are controlled by one microprocessor.

  Usually, in a wattmeter connected to a network, voltage and current sampling processing and arithmetic processing are controlled by one microprocessor provided in the sensor module, and another microprocessor provided in the communication module It is configured to control data exchange and network communication processing between the communication module and the sensor module.

  However, the power meter according to the first aspect of the present invention can process voltage and current sampling processing and arithmetic processing in the sensor module, data exchange with the sensor module in the communication module, and network communication processing by a single microprocessor. Therefore, the cost of the entire wattmeter can be reduced.

  When the voltage and current sampling process (P1) is performed in the power meter according to the first aspect of the invention, the power meter according to the second aspect of the invention is a data calculation process (P2), a data exchange between the communication module and the sensor module, and a network The communication process (P3) enters a standby state, and when the data calculation process (P2) is performed, the voltage and current sampling process (P1), the data exchange between the communication module and the sensor module, and the network communication process (P3) Is in a standby state, and when data exchange and network communication processing (P3) are performed between the communication module and the sensor module, the voltage and current sampling processing (P1) and the data calculation processing (P2) are in the standby state. Thus, control by a microprocessor is performed.

  The microprocessor has a flash memory and a RAM, and voltage and current data sampling is configured to be performed by direct memory access (DMA) sampling. Here, the voltage and current data sampling process (P1), the data calculation process (P2), the data exchange between the communication module and the sensor module, and the network communication process (P3) are each started by an interrupt and executed by one microprocessor. , P1, P2, and P3 can be realized.

  A power meter according to a third aspect of the present invention is the power meter according to the second aspect of the present invention, wherein the sensor module is configured to be able to sample voltages and currents of a plurality of independent electrical equipments, and the sampling process (P1, Control by the microprocessor is performed so that P1 ′ and P1 ″) are processed in a time-sharing manner.

  Here, not only the power data measurement of one electrical facility but also the voltage and current sampling of a plurality of independent electrical facilities can be sampled, so that the usage efficiency of the wattmeter can be improved.

  A power meter according to a fourth aspect of the present invention is the power meter according to the third aspect of the present invention, wherein the sensor module has a switching unit that switches electrical equipment that samples voltage and current, and performs arithmetic processing (P2) or network communication processing (P3). Control by the microprocessor is performed to switch the electrical equipment to be sampled before.

  Here, when performing voltage and current sampling processing (P1) for a specific electrical equipment among the plurality of electrical equipments, first, the switching equipment switches the electrical equipment, thereby performing the arithmetic processing (P2) or The electrical equipment related to the network communication process (P3) can be specified.

  A power meter according to a fifth aspect of the present invention is the power meter according to the first aspect, wherein the control by the microprocessor is configured to adjust the time interval of the voltage and current sampling processing based on the power supply cycle.

  Here, a single microprocessor performs voltage and current sampling processing, arithmetic processing, data exchange with the sensor module, and network communication processing. Therefore, the input voltage waveform and the input current waveform are not sampled seamlessly, but are sampled only for a certain period, so that there is a possibility that an error occurs in the sampling data. Therefore, the power meter according to the fifth aspect of the present invention is configured to adjust the time interval of the voltage and current sampling processing based on the power supply cycle, obtain the optimal sampling interval, and perform the sampling processing at that interval, Errors that occur in the sampling data can be minimized.

  A power meter according to a sixth aspect of the present invention is the power meter according to the first aspect, wherein the control by the microprocessor corrects the current data, the voltage data, or the power data based on the power supply cycle and the sampling interval or the final sampling interval of one cycle. It is configured as follows.

  Here, instead of sampling the input voltage waveform and input current waveform seamlessly, the current data, voltage data, or power data is corrected in order to suppress sampling data errors caused by sampling for a certain period. ing. At that time, by correcting the current data, voltage data, or power data based on the power cycle and sampling interval or the final sampling interval of one cycle, the error that occurs in the sampling data is minimized, and the accuracy of the power meter Can be increased.

  The power meter according to a seventh aspect is the power meter according to the sixth aspect, wherein the control by the microprocessor corrects the current data, the voltage data, or the power data based on a final measurement value of sampling of one cycle of the current or voltage. It is configured.

  Here, in order to suppress an error occurring in the sampling data, the microprocessor performs control so as to correct the current data, the voltage data, or the power data based on the final measurement value of the current or voltage sampling. Therefore, an optimal correction value can be obtained and the accuracy of the wattmeter can be increased.

  A power meter according to an eighth aspect of the present invention is the power meter according to the first aspect, wherein the mounting board of the microprocessor includes a power supply circuit, an analog circuit, and a digital circuit, and the power supply circuit, the analog circuit, and the digital circuit are common. It has a ground connection part.

  Here, for example, the ground part of the power supply circuit, the ground part of the analog circuit, and the ground part of the digital circuit are grounded by one connecting part. If they are grounded at different ground portions, errors in the respective ground portions are likely to occur. Here, since the power supply circuit, the analog circuit, and the digital circuit have a common connecting portion, it is possible to suppress the occurrence of an error between the connecting portions and increase the accuracy of the wattmeter.

  The power meter according to a ninth aspect is the power meter according to the eighth aspect, wherein the amplifier circuit of the analog circuit is a differential amplifier circuit.

  A power meter according to a tenth aspect is the power meter according to the first aspect, wherein the communication module further includes a Web server, and the measured power parameter value can be updated on the Web server page.

  Here, by further providing a web server in the communication module of the power meter, the power parameter measured by the power meter can be transmitted via the network.

  A power monitoring system according to an eleventh aspect includes a power meter having a sensor module, a communication module, and one microprocessor, and a client monitoring device. Among them, the client monitoring device includes power meter management software for displaying data received from the communication module, storing data, or managing the power meter via the network.

  A power monitoring system according to a twelfth aspect of the present invention is the power monitoring system according to the eleventh aspect, wherein the power meter management software is programmed to be executed by the client monitoring device, and from the Web server of the communication module of the power meter through the network. It is transferred to the client monitoring device and executed.

  A power monitoring system according to a thirteenth aspect is the power monitoring system according to any of the eleventh and twelfth aspects, wherein the client monitoring device includes a storage unit, and the power meter management software includes a plurality of power meters connected to the network. The measured value and the calculated value measured in step (1) can be collected for a long time, and the data transferred from the web server of the communication module of the power meter can be collected and stored.

  The power monitoring system according to a fourteenth aspect is the power monitoring system according to any one of the eleventh to thirteenth aspects, wherein the power meter management software sets a data collection sampling start time, a data collection stop time, and a data collection sampling time interval. It is configured to be able to.

  The power monitoring system according to a fifteenth aspect of the present invention is the power monitoring system according to the fourteenth aspect of the present invention, wherein the power meter management software is configured to save the measurement current time together with the measurement value in the storage module of the client monitoring device.

  The power monitoring system according to the eleventh to fifteenth aspects includes a power meter having a sensor module and a communication module, and a client monitoring device. The client monitoring device transmits data received from the communication module via a network. Equipped with wattmeter management software to display, save data or manage wattmeter. Therefore, the power meter according to any one of the first to tenth aspects can be managed via the network.

  As described above, according to the present invention, the following effects can be obtained.

  The power meter according to the first aspect of the present invention can process voltage and current sampling processing and arithmetic processing in the sensor module, data exchange processing with the sensor module in the communication module, and network communication processing by a single microprocessor. Therefore, the cost of the entire wattmeter can be reduced.

  In the power meter according to the second aspect of the present invention, the voltage and current data sampling process (P1), the data calculation process (P2), the data exchange process between the communication module and the sensor module, and the network communication process (P3) are each started by an interrupt. The processing of P1, P2, and P3 can be realized by one microprocessor.

  A power meter according to a third aspect of the present invention is the power meter according to the second aspect, wherein not only the power data of one electrical facility but also the voltage and current of a plurality of independent electrical facilities can be sampled. The use efficiency can be improved.

  The wattmeter according to the invention 4 is performed after sampling by first switching the electrical equipment by the switching unit when performing the voltage and current sampling processing (P1) for the specific electrical equipment among the plurality of electrical equipments. It is possible to specify the electrical equipment related to the calculation process (P2) or the network communication process (P3).

  The power meter according to the fifth aspect of the present invention is configured to adjust the time interval of the voltage and current sampling processing based on the power supply period, obtains the optimum sampling interval, and performs the sampling processing at the interval, thereby obtaining the sampling data Can be minimized.

  The power meter according to the sixth aspect of the present invention minimizes errors occurring in the sampling data by correcting the current data, voltage data, or power data based on the power cycle and the sampling interval or the final sampling interval of one cycle. The accuracy of the power meter can be increased.

  The power meter according to the seventh aspect is controlled by the microprocessor so as to correct the current data, the voltage data, or the power data based on the final measurement value of the sampling of one cycle of the current or voltage. Therefore, an optimal correction value can be obtained and the accuracy of the wattmeter can be increased.

  In the power meter according to the eighth aspect of the present invention, the power supply circuit, the analog circuit, and the digital circuit have a common connection portion, so that the occurrence of an error between the connection portions can be suppressed and the accuracy of the power meter can be improved.

  The power meter according to a ninth aspect is the power meter according to the eighth aspect, wherein the amplifier circuit of the analog circuit is a differential amplifier circuit.

  The wattmeter according to the tenth aspect of the invention can further transmit a power parameter measured by the wattmeter via the network by further including a Web server in the communication module of the wattmeter.

  The power monitoring system according to the eleventh to fifteenth aspects includes a power meter having a sensor module and a communication module, and a client monitoring device. The client monitoring device transmits data received from the communication module via a network. Equipped with wattmeter management software to display, save data or manage wattmeter. Therefore, the management of the functions described in any one of Inventions 1 to 10 can be performed via the network.

  A power meter and a power monitoring system according to the present invention will be described based on the attached drawings and examples.

  FIG. 1 is an external view of a wattmeter 100 according to the present invention capable of simultaneously measuring the power of a single-phase two-wire electric circuit and the power of a three-phase three-wire electric circuit. Here, the main body frame 1 of the wattmeter is provided with a plurality of connecting portions 11. Here, the current sensor 2 and the transformer 3 of the single-phase two-wire electric circuit, and the current sensors 6 and 7 and the transformer 4 of the three-phase three-wire electric circuit are respectively connected to the connecting portion 11 through electric wires.

  As shown in FIG. 1A, the single-phase two-wire electric circuit and the three-phase three-wire electric circuit are independent channels. Therefore, the client monitoring device sets the type of the electric circuit of the electric equipment as necessary, and the line voltage 9, 10 with the electric circuit such as single-phase two-wire, single-phase three-wire and three-phase three-wire is set. If it is less than 240V, the transformers 3 and 4 in FIG. 1 can be omitted. Since the current sensors 2, 6, and 7 are clamped as shown in FIG. 1B, they can be easily attached without additional wiring work.

  In addition, this power meter can measure any channel independently. At that time, a signal from a channel not to be measured is not input. Furthermore, since the power meter can supply power to the power meter by using the voltage from channel 1 or channel 2 as an input to the power module of the power meter, it is not necessary to provide a separate power source.

FIG. 2 is a system block of the power meter 100 according to the present invention. As shown in FIG. 2, the wattmeter 100 includes a sensor module 12 and a communication module 13.
The sensor module STIM12 includes a built-in transformer (not shown), an electronic database TEDS12a, a data exchange register 12b, an electrical parameter calculator 12c, and an analog signal adjuster 12d. The power meter is also managed at the same time as sampling processing, calculation processing of sampled parameters, and the like. The electrical signal of the electrical facility is input as a weak alternating current signal by the external current sensors 2, 6, 7 and the built-in transformer.

  The input weak AC signal is converted into a DC signal of 0 to 5V by the analog signal adjuster 12d. The electrical parameter calculator 12c samples a DC signal of 0 to 5V, and the voltage effective value, current effective value, power factor, frequency, active power, power factor, integration based on the sampling voltage instantaneous value and current instantaneous value. Performs calculations such as active power and integrated reactive power. The electronic database TEDS 12a includes the IP address of the wattmeter, the MAC address, the recognition of the type of the electric circuit of the electrical equipment measured by the wattmeter, the transformation ratio of the transformer and current sensor used, the setting of the current transformation ratio, This is for managing the power consumption of the equipment.

  The communication module NCAP 13 includes a data exchange register 13a, a TCP / IP processor 13b, a Web server 13c, a TCP / IP interface 13d, a network controller 13e, and the like. This is for performing communication processing. Here, the network controller 13e is for transmitting and receiving network data as an interface between the power meter and Ethernet (registered trademark).

  TCP / IP interface 13d realizes address analysis protocol ARP, Internet protocol IP, user data protocol UDP, network message control protocol ICMP, transmission control protocol TCP and hypertext transfer protocol HTTP, and analyzes and packages network data Process.

  When data is received, the TCP / IP processor 13b reads the data from the reception buffer of the network controller 13e, and headers corresponding to the link layer, network layer, transport layer, and application layer for the data. Processing, packet processing, data processing, etc. are performed.

  When transmitting data, the TCP / IP processor 13b performs header processing, packet processing, data processing, and the like by a process reverse to that at the time of reception to create transmission data. The transmission data is written in the transmission buffer of the network controller 13e, and data transmission is performed by a transmission command.

  The Web server 13c manages the home page and stores a home page display file in the storage device. For example, a FLASH memory device or the like is used as the storage device.

  Here, the sensor module 12 and the communication module 13 share one microprocessor 60, and the microprocessor 60 performs the data calculation process P2, the data exchange process between the communication module and the sensor module, and the network communication process. P3 is performed.

  FIG. 3 is an electric circuit block of the sensor module portion of the wattmeter 100 according to the present invention. As shown in FIG. 3, the sensor module of the power meter 100 according to the present invention mainly includes a switch power supply module electric circuit 16, a memory module electric circuit 15, a CPU module electric circuit 14, a network interface module electric circuit 17, and The signal switching processing module electric circuit 18 is configured.

  Here, the switch power supply module electric circuit 16, the CPU module electric circuit 14, and the signal switching processing module electric circuit 18 are grounded to the ground by a common connecting portion. The amplifier circuit of the signal change processing module electric circuit 18 is a differential amplifier circuit.

  Further, the switching power supply module electric circuit 16, the CPU module electric circuit 14, and the signal switching processing module electric circuit 18 have an analog circuit power supply and a GND, a digital circuit power supply and a GND, respectively, which are not influenced by each other. The power supply for the digital circuit and the power supply for the digital circuit are connected by a common connecting portion, and the GND for the analog circuit and the GND for the digital circuit are connected by a common connecting portion. That is, they are connected by so-called one-point GND. Therefore, the analog circuit and the digital circuit are highly independent, unnecessary noise is less likely to be mixed into other parts of the electric circuit, and a stable signal processing circuit can be realized.

Further, the circuit that is provided in the input stage of the signal switching processing unit and amplifies the input signal is constituted by a differential amplifier circuit. The AC current signal of 0 to 30 mA acquired by the external current sensors 2, 6 and 7 shown in FIG. 2 and the AC weak voltage signal A acquired from the built-in transformer are 0V after passing through the analog signal regulator 12d. It is converted to a weak electric signal of ~ 5V.
The switching electric circuit 18c switches the input to the CPU module circuit 14 to either the input electric circuit 1 (18a) or the electric circuit 2 (18b) according to a command from the microprocessor 60.

  The microprocessor 60 sets the time interval between the sampling process and the A / D conversion process for the channel 1 and the channel 2, performs the calculation process on the sampling data, and calculates the numerical value of the electrical parameter. The CPU module electrical circuit 14 also performs TCP / IP protocol processing in addition to electrical parameter sampling processing and arithmetic processing.

  The electric circuit 15 of the memory module is composed of, for example, a 512 KB FLASH memory and a 32 KB SRAM. The FLASH memory and the SRAM are used for storing English and Chinese homepages and temporary data, respectively. The network interface module electric circuit 17 constitutes an interface between the wattmeter 100 and the Internet, and realizes information exchange between the wattmeter 100 and the outside. The power supply module 16 receives, for example, the voltage of the channel 1 and outputs a DC voltage of 5 V through a rectifying filter, thereby serving as a power source for the wattmeter.

  FIG. 4A shows the waveform of the current signal acquired by the current sensors 2, 6, and 7 and the voltage signal acquired by the built-in transformer, 19 is a voltage signal, and 20 is a current signal. FIG. 4B shows a pulse signal 21 generated by pulse-shaping a voltage signal by an operational amplifier circuit.

  The pulse signal is sent to the external interrupt terminal of the microprocessor, the microprocessor performs interrupt processing at the falling edge of the pulse signal, and sampling processing is performed by the interrupt processing.

  After the interrupt reset process is performed, the microprocessor 60 executes a data calculation process P2, a data exchange process between the communication module and the sensor module, a network communication process P3, and the like. This series of processes is performed for each measurement channel. Repeatedly.

In FIG. 4, the synchronous pulse signal 21 generated by the voltage signal 19 is used as a counter signal source of the microprocessor 60. When reset, the three steps P1, P2, P3 of the IP power meter are in a standby state. When the first frequency of the voltage signal is sent, that is, at time t ₀ , an interrupt accompanying a level change occurs at the external interrupt terminal of the microprocessor 60. In the interrupt process, the sampling indicator is set to 1, and the voltage / current signal sampling P1 process is started. At the first frequency of the voltage signal 19, the microprocessor 60 samples the voltage signal 19 and current signal 20 of the channel 1 (18a) and stores the sampling data in the RAM. When the sampling process P1 step is executed, P2 and P3 are in a standby state. At time t ₁ , an interrupt associated with a level change occurs again at the external interrupt terminal of the microprocessor 60. At the same time as the sampling indicator is set to 0 in the interruption process, the electric parameter calculation indicator is set to 1, the P2 process is executed, and P1 and P3 are in a standby state. The microprocessor 60 calculates eight electrical parameter values such as an effective voltage value and an effective current value based on the sampled voltage signal and current signal. When the calculation of the electrical parameter value is completed, the accumulated values of active power and reactive power are stored in the microprocessor internal data FLASH memory.

In t ₂ time, if the electrical parameter calculation indicator has been set to 0, in the voltage cycle of the N-2, P1, P2 is in a standby state, P3 process is performed. The microprocessor 60 performs communication processing in response to a request from the client monitoring device. Here, the time t ₂ is an indeterminate value, which is determined by the frequency of the voltage signal and the calculation amount, and the electric parameter calculation time is within 1 or 2 frequencies. After the network communication process is completed at the N-2 frequency, the microprocessor 60 switches to a different channel and performs the same process. By repeating such a cycle, it is possible to realize the voltage / current signal sampling processing P1, the electrical parameter value calculation processing and storage processing P2, and the network communication processing P3 by time division processing using a single microprocessor. it can.

  FIG. 5 shows the voltage / current signal sampling process P1. Here, 19 'is a voltage signal and 20' is a current signal. After setting the sampling indicator to 1 in the external interrupt process, the microprocessor timer is started. At this time, the set time is set to ΔT, and the timer mode is set to the continuous counter mode.

  When the set time is reached, a timer interrupt is generated, and current signal and voltage signal sampling processing is started by DMA (Direct Memory Access) processing.

  After the sampling is completed, the sampling result is stored in the designated memory. Wait until the next timer interrupt occurs. When the timer interrupt occurs, sampling by the next DMA processing is started and performed until the sampling indicator is released.

  Here, a method for correcting the sampling leakage of the voltage signal and the current signal will be described by taking correction of sampling leakage of the current signal as an example.

  Here, a method of correcting a phenomenon (hereinafter referred to as “sampling leakage”) in which an error occurs in an effective value due to a sampling error of a current signal and a voltage signal will be described.

  Usually, the effective value of the continuous voltage signal u is calculated based on the equation (1).

  When the effective value of the voltage signal u is obtained from the voltage value sampled at discrete time (sampling number is N), the effective value of the voltage signal is calculated based on Expression (2).

  In Equation (2), it is assumed that the signal period of the voltage signal u is equally divided into N sample periods as shown in FIG. However, in an actual usage environment, the signal cycle of the input signal is not always constant, and there may be a deviation. Further, if the signal processing circuit is unstable, it causes a slight change in the signal period, and it is difficult to ensure that the signal period T is equally divided into N sample periods. For this reason, an error is likely to occur in the calculation result by the equation (2). This is the so-called sampling leakage shown in FIG. FIG. 7A shows a pulse signal of a voltage signal. In FIG. 7B, 19a represents a voltage signal, and 20a represents a current signal. FIG. 7C is an enlarged view of the broken line portion of FIG. In FIG. 7, the voltage and current signal periods are not equally divided by the sample period TS. That is, since the interval between t1 and t2 is shorter than the sample period TS, sampling leakage occurs. The hatched portions A and B in FIG. 7C represent the sampling leakage of the voltage signal and the sampling leakage of the current signal, respectively.

  Therefore, by calculating the effective value of the current signal based on Expression (3), it is possible to correct sampling leakage of the current signal and ensure the accuracy of sampling.

  Thereby, the effective value of the current signal with less error can be acquired. Note that the effective value of the voltage signal with less error can be obtained by the same correction for the voltage value.

As can be seen from FIG. 7, i ₀ = i _N. When the interval between t2 and t1 is made minute, it can be assumed that i _N ≈i _N−1 . Therefore, the following equation (4) is obtained from the equation (3).

In Expression (4), (t ₂ −t ₁ ) is an unknown number. This unknown number may be calculated using T, TS, and N. Alternatively, for example, the counter value of a binary counter is read at time t2 when an external interrupt occurs in order to calculate the interval between t2 and t1. . There is also a method of calculating the time interval between t2 and t1 by increasing the count value of the binary counter. Theoretically, an almost accurate value of the current signal can be obtained by the above correction.

  Next, the power monitoring system will be described. The power monitoring system 200 illustrated in FIG. 8 displays the data received from the communication module 13, stores data, or manages the power meter 100 on the power meter 100 including the sensor module 12 and the communication module 13 illustrated in FIG. 2. A client monitoring device 60 equipped with wattmeter management software is further added.

  FIG. 9 shows the exchange between the client monitoring device 80 of the client and the Web server 13 c of the power meter 100. First, when a communication start request (Request) is made from the client monitoring device 80 to the Web server 13c of the power meter 100, a response (ACK) is made from the Web server 13c to the client monitoring device 80. Thereafter, when a data transfer request is made from the client monitoring device 80, the data is transferred from the Web server 13c to the client monitoring device 80, and the screen shown in FIG. At the top of the screen there are three icons related to the placement of the power meter: reading the electrical circuit type and PT / CT ratio 22, setting the electrical circuit type and PT / CT ratio 23, resetting the integrated active power / integrated reactive power 24.

  When the reading icon in the “Reading electric circuit type and PT / CT ratio” tab 22 is clicked on the client monitoring terminal device 80, the electric circuit type and the PT / PT of the two passages of the wattmeter are displayed in the icon display area 25. The CT ratio is displayed. When the “Electrical circuit type and PT / CT ratio setting” tab 23 icon is clicked, a screen as shown in FIG. 11 is displayed in the icon display area 25 in FIG. Here, the client monitoring device 80 can set the electric circuit type and PT / CT rate of the two channels of the power meter. In addition, the type of electric circuit can be selected among single-phase two-wire, single-phase three-wire, and three-phase three-wire through a pull-down menu.

  Clicking the “Accumulated active power / integrated reactive power reset” 24 tab displays the screen shown in FIG. 12 in the icon display area 25 in FIG. 10, and clears the accumulated values of the two channels by different combinations. can do. The channel selection 27 is selected between two channels of the wattmeter. When a certain channel is selected, the current value 29 and the integrated value 30 are displayed as numerical values of the electrical parameters of the selected channel. In order to improve the performance of the power meter, all the data exchange processing between the client monitoring terminal device 80 and the power meter 100 described above is performed by UDP. The client monitoring terminal device 80 makes a data transfer request to the wattmeter 100 by UDP every second and updates the data displayed on the Web page.

  The power meter management software includes “data collection software” (FIG. 13) and “IP address setting and Web server upload software” (FIGS. 14 and 15).

  “Data collection software” is for collecting data collected by a power meter over a long period of time in a LAN. Using this software, it is possible to collect the electricity usage status data of the electrical equipment, save the collected data in a CSV format file, and refer to it when the client performs equipment maintenance. In the screen shown in FIG. 13, data of eight power meters 100 in the LAN can be collected at the same time, and the IP address of the power meter can be input in the IP address input section 32. In the time setting section 33, the data sampling start time, stop time, and sampling interval can be set. Data of one wattmeter 100 can be saved as one file, and a directory of the file can be arbitrarily selected and saved. The file name is a combination of the sampling start time and the IP address of each power meter. Each time one piece of data is collected, the client transmits a UDP packet to the power meter 100 to make a data transfer request, and the power meter 100 transmits the numerical data of the latest electrical parameters to the client monitoring terminal device 60 by UDP. .

  As shown in FIG. 14, “IP address setting and homepage upload software” is for designating the IP address AAA of the power meter 100 designated in the LAN.

  The client monitoring terminal device 60 sets the IP address of the power meter 100 as a communication destination, and communicates with the power meter 100 using the AAIP address A.

  The power meter 100 that is the communication destination acquires data corresponding to an electronic database TEDS (Transducer Electronic Data Sheet) compliant with IEEE 1451 of the sensor module 12 and stores the data as TEDS format data.

  The TEDS format data acquired by the wattmeter 100 can be viewed by the client monitoring terminal device 60 via communication.

  For example, HTML format data can be generated from TEDS format data by the Web server 13 c of the wattmeter 100 and communication by HTTP can be performed so that the client monitoring terminal device 60 can view the data. In this case, every time the TEDS format data is updated, the HTML format data generated by the wattmeter 100 is also updated and stored in the memory module 15, and the client monitoring terminal device 60 stores the data in the wattmeter 100. By issuing a browsing request to the Web server 13c, the acquired data in the client monitoring terminal device 100 can be updated.

  In addition, a JAVA (registered trademark) applet for displaying TEDS format data in real time on the Web server 13c of the wattmeter 100 is prepared, and the client monitoring terminal device 60 downloads and operates the applet, thereby monitoring the client in real time. Data acquired by the sensor module 12 of the power meter 100 may be browsed by the terminal device 60.

(A) Schematic appearance of wattmeter (b) Enlarged view of sensor connection Power meter system block diagram Electric meter block diagram of wattmeter (A) The figure showing the waveform of a voltage signal and an electric current signal (b) The figure showing the voltage pulse signal Diagram showing sampling process of voltage signal and current signal Diagram showing signal cycle of voltage signal (A) Diagram showing voltage pulse signal (b) Diagram showing leakage of voltage signal and current signal sampling (c) Enlarged view of broken line portion of FIG. 7 (b) Power meter monitoring system schematic Schematic diagram of power meter monitoring system communication Screen downloaded from wattmeter web server Display screen showing electrical circuit type and PT / CT ratio Display screen when resetting accumulated active power / integrated reactive power Display screen during data collection Display screen showing IP layout Display screen showing Web server upload

Explanation of symbols

1 Power meter body frame 2 Channel 1 current sensor 3 Channel 1 transformer 4 Channel 2 transformer 5 RJ-45 interface 6 Channel 2 first current sensor 7 Channel 2 second current sensor 8 Net connection 9 Single-phase two-wire power line 10 Three-phase three-wire power line 11 Transformer and current sensor connection 12 Sensor module 13 Communication module.
14 Microprocessor module electric circuit 15 Memory module electric circuit 16 Switch power supply module electric circuit 17 Network interface module electric circuit 18 Signal switching processing module electric circuit 18a Electric circuit 1 signal processing module electric circuit 18b Electric circuit 2 signal processing module electric Circuit 18c An electric circuit for switching between the electric circuit 1 and the electric circuit 2.
19 Voltage signal 20 Current signal 21 Voltage pulse signal 22 Icon for reading electric circuit type and PT / CT ratio 23 Icon for setting electric circuit type and PT / CT ratio 24 Icon 25 for resetting accumulated power and accumulated reactive power 25 Icon Display area 26 Selected circuit electric circuit type display icon 27 Channel selection icon 28 Current time display 29 Current value 30 Integrated value 31 Number of power meter selection icon 32 Power meter IP address input area 33 Time setting area 34 Saved file path Setting area 35 Start and stop button 36 Status bar 60 Microprocessor 80 Client monitoring measure 100 Wattmeter 200 Wattmeter monitoring system

Claims (15)

A sensor module that performs sampling processing of the voltage and current values of the electrical equipment and performs calculation processing of current data, voltage data, and power data from the sampled measurement values;
A communication module for performing data exchange processing with the sensor module and network communication processing by the TCP / IP protocol;
In the wattmeter including one microprocessor, the voltage and current sampling processing and calculation processing in the sensor module, and data exchange processing and network communication processing with the sensor module in the communication module are controlled by one microprocessor. Power meter. Control by the microprocessor is
When the voltage and current sampling process (P1) is performed, the data calculation process (P2), the data exchange process between the communication module and the sensor module, and the network communication process (P3) are in a standby state.
When the data calculation process (P2) is performed, the voltage and current sampling process (P1), the data exchange process between the communication module and the sensor module, and the network communication process (P3) are in a standby state.
When the data exchange process and the network communication process (P3) between the communication module and the sensor module are performed, the voltage and current sampling process (P1) and the data calculation process (P2) are controlled to be in a standby state. The wattmeter according to claim 1 to be performed.   The sensor module is configured to be able to sample voltages and currents of a plurality of independent electrical installations, and the microprocessor controls the sampling of the plurality of electrical installations (P1, P1 ′, P1 ″). The wattmeter according to claim 2, which is executed by time division.   The sensor module includes a switching unit that switches an electrical facility for sampling voltage and current values, and the control by the microprocessor is performed before the arithmetic processing (P2) or the network communication processing (P3) is performed. The wattmeter according to claim 3 which switches.   The power meter according to claim 1, wherein the control by the microprocessor adjusts a time interval of the sampling process of the voltage and current based on a power supply cycle.   The power meter according to claim 1, wherein the control by the microprocessor corrects current data, voltage data, or power data based on a power supply cycle and a sampling interval.     The power meter according to claim 6, wherein the control by the microprocessor corrects current data, voltage data, or power data based on a final measurement value of sampling of current or voltage values.   The mounting board of the microprocessor includes a power supply circuit, an analog circuit, and a digital circuit, and the power supply circuit, the analog circuit, and the digital circuit are connected by a common connecting portion. Wattmeter.   The power meter according to claim 8, wherein the amplifier circuit of the analog circuit is a differential amplifier circuit. The communication module further includes a web server,
The power meter according to claim 1, wherein the measured power parameter value can be updated on the Web server page. A power meter having a sensor module, a communication module and one microprocessor, and a client monitoring device;
Among them, the client monitoring device includes a power meter management software for displaying data received from the communication module, storing data, or managing a power meter via a network.   The power meter management software is programmed to be executed by a client monitoring device, and is transferred from the Web server of the communication module of the power meter to the client monitoring device and executed through a network. The power monitoring system described in 1. The client monitoring device includes a storage unit, and the power meter management software can collect measured values and calculated values measured by a plurality of power meters connected to a network for a long time,
The power monitoring system according to claim 11, wherein the data transferred from the web server of the communication module of the power meter can be collected and stored.   The power monitoring system according to claim 11, wherein the power meter management software is configured to set a data collection sampling start time, a data collection stop time, and a data collection sampling time interval.   The power monitoring system according to claim 11, wherein the power meter management software can store the measurement value and the measurement time of the measurement value in a storage module of a client monitoring device.

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