KR102042964B1 - Wireless monitoring system for photovoltaic generating apparatus - Google Patents

Abstract

The wireless sensing system of a grid-connected photovoltaic device according to the present invention, a solar power module for generating direct current power by converting solar energy into electrical energy, and converts the direct current power output from the solar power module into alternating current power. To monitor the operating state of the photovoltaic device based on the inverter, a detector for measuring the amount of reverse power transmitted from the inverter to the power system and a power factor of the customer and transmitting the power factor to the inverter, and monitoring information transmitted from the inverter through wireless communication. And a wireless terminal for controlling the operation of the inverter. Therefore, the inverter has a function to control reverse power transmission to the power system and a power factor of the consumer to maximize the use efficiency, and to easily control the monitoring and operation of the photovoltaic device through the wireless terminal of the administrator. Can be. In addition, it is possible to monitor the state of the connection panel through the camera device installed in the connection panel in which the inverter is installed, and to check the photographed image through the wireless terminal to monitor fire prevention.

Description

Wireless sensing system of grid-connected photovoltaic device {WIRELESS MONITORING SYSTEM FOR PHOTOVOLTAIC GENERATING APPARATUS}

The present invention relates to a wireless sensing system of a grid-connected photovoltaic device for supplying power to a customer in connection with a power system. More particularly, the present invention relates to a power factor of a power and a customer reversely transmitted from a photovoltaic system to a power system. It relates to a wireless sensing system of a grid-connected photovoltaic device having a function to control.

Recently, in order to save energy and protect the environment, a grid-connected photovoltaic power generation system that actively supplies power to a specific customer by linking a distributed power source using a photovoltaic power generation system with an existing power system has been actively developed.

 In the case of using the distributed power source using the power system and the photovoltaic power generation system as described above, if the amount of power generated in the photovoltaic power generation system exceeds the usage of its own load, reverse transmission to the power system occurs, which adversely affects the power quality. Go crazy.

Accordingly, the current law stipulates that the reverse transmission prevention device is mandatory to install power generation facilities of 50KW or more.

In the conventional reverse transmission prevention device, when the amount of power generation of the photovoltaic power generation system exceeds the usage of the load and the reverse transmission is performed to the power system, the reverse transmission power is detected by the reverse power relay and signaled to the shunt breaker, and the operation of the shunt breaker Through the configuration of forcibly blocking the inverter of the photovoltaic power generation system.

As such, by forcibly cutting off the use of the photovoltaic power generation system when a backfeed occurs, a problem of lowering the efficiency of use of the photovoltaic power generation system occurs.

In addition, since the grid-connected solar power generation system does not generate electricity constantly, but the amount of generation depends on the change in the amount of insolation, the surrounding climate and the time, the small-scale solar power generation system will not affect the power system of the customer. However, since a relatively large photovoltaic power generation system may cause power factor fluctuations in a customer's system, a technique for compensating power factor by controlling the output of a grid-connected inverter of a photovoltaic power generation system is required.

(Patent Document 1) KR1700290 B1

Therefore, in view of the above problems, the present invention incorporates a function for controlling reverse power transmission to a power system and a power factor of a consumer to the inverter to improve the efficiency of use at the same time and to provide solar power through a wireless terminal of a manager. The present invention provides a wireless sensing system of a grid-connected photovoltaic device that can easily control and monitor the power generation device.

The wireless sensing system of a grid-connected photovoltaic device according to an embodiment of the present invention, the solar power module for generating direct current power by converting solar energy into electrical energy, the direct current power output from the solar power module Based on the inverter converting the AC power into AC power, the amount of reverse power transmitted from the inverter to the power system, the detector measuring the power factor of the customer and transmitting the power factor to the inverter, and the monitoring information transmitted from the inverter through wireless communication. It includes a wireless terminal for monitoring the operation state of the photovoltaic device and control the operation of the inverter.

The detection unit includes a reverse power relay for measuring the amount of reverse power transmitted from the inverter back to the power system, and a power meter for measuring the power factor of the customer.

The inverter, a power conversion unit for converting the DC power output from the photovoltaic module into AC power, the maximum power point tracking to control the output power from the photovoltaic module to be operated at the operating point to produce the maximum power A control unit, a reverse power transmission control unit for controlling the power transmitted back to the power system through the control of the maximum power point tracking control unit based on the reverse power transmission information transmitted from the reverse power relay, based on the power factor information transmitted from the power meter A power factor control unit may control the power factor of the consumer through the control of the power converter, and a wireless communication unit for wireless communication with the wireless terminal.

The reverse transmission control unit controls the reverse transmission control mode to adjust the output power of the inverter when the amount of reverse transmission power measured by the reverse power relay is equal to or less than a set threshold capacity, and the reverse transmission power amount measured by the reverse power relay is When the limit capacity is exceeded, the inverter is controlled to an output blocking mode that blocks the output of the inverter. When the reverse power transmission is not detected by the reverse power relay, the maximum power point following control unit performs the maximum power point following function in a normal state. Control to the maximum power point following mode to perform.

The reverse power transmission controller is configured to adjust the amount of power corresponding to the measured amount of reverse power transmission in the reverse power transmission control mode, instead of the first operating point that produces the maximum power in the normal state. It can be controlled to operate at 2 operating points.

The power factor controller compares the power factor measured by the electricity meter with a predetermined target power factor, and when the measured power factor is determined to be out of the target power factor, the power factor of the consumer falls within the target power factor. The power factor may be controlled by controlling at least one of active power and reactive power of the power output from the converter.

The wireless terminal may include a control application for monitoring the operating state of the photovoltaic device and controlling the operation of the inverter.

According to the wireless sensing system of the grid-connected photovoltaic device, the operation mode of the inverter is based on the reverse transmission control mode, the output cutoff mode, and the maximum power, depending on whether the reverse transmission occurs to the power system and the magnitude of the reverse transmission power. In the reverse transmission control mode, the output power of the inverter is controlled by controlling the position of the operating point in the maximum power point following controller in the reverse power transmission control mode. Use efficiency can be improved.

In addition, by embedding a function to control the power factor in the inverter, it is possible to minimize the stabilization and power loss of the power system, and to reduce the electric bill as much as possible.

In addition, it is possible to easily control the operation of the monitoring and monitoring of the operation state of the photovoltaic device through the wireless terminal of the manager.

1 is a schematic configuration diagram of a wireless sensing system of a grid-connected photovoltaic device according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating in detail the configuration of the detector and the inverter illustrated in FIG. 1.
3 is a flowchart illustrating a method for controlling the power transmission and power factor of an inverter according to an embodiment of the present invention.
4 is a view for explaining a control method in the reverse power transmission control mode of the inverter.
5 is a view showing an example of parallel operation of the conventional load and photovoltaic power generation in the consumer.
6 is a diagram illustrating an example of a power factor control method according to the present invention.

The above-described features and effects of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, and thus, those skilled in the art to which the present invention pertains may easily implement the technical idea of the present invention. Could be. As the inventive concept allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "having" are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described in the specification, and that one or more other features It should be understood that it does not exclude in advance the possibility of the presence or addition of numbers, steps, actions, components, parts or combinations thereof. Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic configuration diagram of a wireless sensing system of a grid-connected photovoltaic device according to an embodiment of the present invention, and FIG. 2 is a configuration diagram illustrating the configuration of the detector and the inverter shown in FIG. 1 in more detail.

1 and 2, a wireless sensing system of a grid-connected photovoltaic device according to an embodiment of the present invention provides a power supply to a load 200 of a specific customer in connection with a power system 100. Regarding the wireless sensing system of the photovoltaic device, the solar power module 300 that converts solar energy into electrical energy to produce direct current power, and converts the direct current power output from the solar power module 300 into alternating current power. An inverter 400 for supplying the load 200 to the load 200, a detector 500 for measuring the amount of reverse power transmitted from the inverter 400 to the power system 100 and a power factor of the consumer and transmitting the power factor to the inverter 400, and It includes a wireless terminal 600 for monitoring the operation state of the photovoltaic device and control the operation of the inverter 400 based on the monitoring information transmitted from the inverter 400 through wireless communication.

The photovoltaic module 300 is a photovoltaic cell that absorbs solar energy and converts it into electrical energy, and has a configuration in which solar cells, which are the smallest unit of a solar cell, are connected in series, in parallel, or in parallel. The photovoltaic module 300 may be installed on a roof or wall of a building.

The inverter 400 converts the direct current power output from the photovoltaic module 300 into an alternating current power that can be used in the load 200 in connection with a power system that provides commercial power. Supplies).

When the photovoltaic power output from the inverter 400 is supplied to the load 200 of the consumer, when the photovoltaic power output from the inverter 400 is greater than the usage amount of the load 200, the power system 100. Reverse transmission may occur. In order to detect such reverse transmission information, the detection unit 500 includes a reverse power relay 510.

The reverse power relay 510 is installed on the power supply line of the power system 100, and when reverse transmission occurs from the inverter 400 to the power system 100, the reverse power transmission is reversely transmitted to the power system 100. Detects and measures the amount of reverse transmission power, and transmits the reverse transmission information related to this to the inverter 400. For example, the reverse power relay 510 detects reverse power transmission and measures reverse power at regular time intervals, and transmits reverse power transmission information measured through an internal or external communication interface to the inverter 400. .

On the other hand, the detector 500 may further include a power meter 520 for measuring the power factor of the consumer. The electricity meter 520 is installed on the power supply line of the power system 100, and during normal photovoltaic operation, measures the power factor of the customer and transmits power factor information related thereto to the inverter 400. For example, the electricity meter 520 measures the power factor at regular time intervals, and transmits the measured power factor information to the inverter 400 through a communication interface disposed inside or outside.

Wireless sensing system of a grid-connected photovoltaic device according to an embodiment of the present invention is at least one of the function of controlling the power back to the power system 100 in the inverter 400, and the power factor of the customer Is built in. In order to implement such a function, the inverter 400 may include a power converter 410, a maximum power point following controller 420, a reverse power transmission controller 430, and a power factor controller 440.

The power converter 410 converts the DC power output from the photovoltaic module 300 into AC power suitable for use of the load 200.

The maximum power point following controller 420 performs a function of controlling the output power from the photovoltaic module 300 to be operated at an operating point that produces the maximum power. In general, the output of the photovoltaic module 300 is characterized in that the voltage and current changes non-linearly according to the surrounding environment, such as solar radiation, temperature, clouds, etc., the output of the solar non-linearly varies by the surrounding environment As a technique for obtaining the maximum power in the photovoltaic module 300, a maximum power point tracking (MPPT) control technique is applied. In other words, MPPT control refers to a technology that automatically tracks the maximum power point to the operating point of the system so that the maximum power can be stably produced from the photovoltaic power generation system whose output varies nonlinearly by the surrounding environment.

The reverse transmission control unit 430 controls the power reversely transmitted to the power system 100 through the control of the maximum power point follower control unit 420 based on the reverse transmission information transmitted from the reverse power relay 510. That is, the reverse transmission control unit 430 determines the operation mode of the inverter 400 in the reverse transmission control mode, the output cutoff mode, and the maximum power point according to whether the reverse transmission to the power system 100 occurs and the magnitude of the reverse transmission power amount. Control to perform the operation by changing to the following mode.

The power factor controller 440 controls the power factor of the customer through the control of the power converter 410 based on the power factor information transmitted from the electricity meter 520. That is, the power factor controller 440 controls the power factor of the customer in consideration of the power and power factor of the load 200 disposed in the customer, the output power and the power factor of the photovoltaic module 300, and the like.

3 is a flowchart illustrating a method for controlling the power transmission and power factor of an inverter according to an embodiment of the present invention.

Referring to FIGS. 2 and 3, reverse transmission information such as whether reverse transmission occurs and reverse power amount measured by the reverse power relay 510 is transmitted to the reverse transmission control unit 430 installed in the inverter 400 through a communication means. It is transmitted (S100).

The reverse transmission control unit 430 compares the reverse transmission information transmitted from the reverse power relay 510 with setting information such as a preset limit capacity and determines the operation mode of the interlock 400 (S200).

For example, when the reverse transmission is detected by the reverse power relay 510 and the measured reverse transmission power amount P1 is determined to be less than or equal to the preset limit capacitance P2, Control in the reverse transmission control mode for adjusting the output power (S300). Typically, when the amount of power back-transmitted to the power system 100 exceeds 20% of the design capacity of the photovoltaic module 300, the output of the inverter 400 should be blocked to prevent reverse transmission, so the limit The capacity P2 may be set to a value corresponding to 20% of the design capacity of the photovoltaic module 300. For example, when the design capacity of the photovoltaic module 300 is 100 kW, the limit capacity P2 is set to 20 kW corresponding to 20% of the design capacity, and accordingly, the reverse power transmission controller 430 measures When it is determined that the amount of reverse transmission power P1 is 20 kW or less, the operation of the inverter 400 is controlled in the reverse transmission control mode.

4 is a view for explaining a control method in the reverse power transmission control mode of the inverter.

Referring to FIG. 4, since the output of the photovoltaic module 300 has a characteristic of changing nonlinearly according to the surrounding environment, the power is normally controlled through the control of the maximum power point following controller 420. do.

However, when reverse transmission occurs in the power system 100, the reverse transmission control unit 430 controls the inverter 400 through the control of the maximum power point following control unit 420 so that the reverse transmission power amount does not exceed a preset limit capacity. Control the operation of the inverter 400 in the reverse power transmission control mode (S300) for adjusting the output power of the.

In detail, in the reverse transmission control mode S300, the reverse transmission control unit 430 reverses the reverse of the first operating point MPP1 that produces the maximum power in the normal state. The controller 100 operates to operate at the second operating point MPP2 adjusted by the amount of power corresponding to the amount of reverse transmission power measured by the power relay 510. That is, in the reverse power transmission control mode S300, the maximum power point following controller 420 operates as much as the amount of power corresponding to the measured reverse power amount instead of following the first operating point MMP1 that substantially produces the maximum power. The second operating point MPP2 whose position of the point is changed is followed, so that the power output from the inverter 400 is substantially reduced.

As such, when reverse transmission to the power system 100 occurs, the maximum power point following control unit 420 controls to follow the operating point adjusted by the amount of power corresponding to the amount of reverse transmission power, the power system 100 The output of the inverter 400 may be controlled such that the power reversely transmitted does not exceed the limit capacity P2 that should completely cut off the output of the inverter 400. As such, even if reverse power transmission to the power system 100 occurs, by adjusting the output power of the inverter 400 such that the amount of reverse power does not exceed the limit capacity P2 forcibly blocking the inverter 400, The utilization efficiency of a photovoltaic system can be improved to the maximum.

On the other hand, the reverse transmission control unit 430, when it is determined that the amount of reverse transmission power (P1) measured by the reverse power relay 510 exceeds the limit capacity (P2), the output blocking to block the output of the inverter 400 Control in the mode (S400). For example, when the design capacity of the photovoltaic module 300 is 100 kW, when the reverse power transmission controller 430 determines that the measured reverse power amount P1 exceeds 20 kW, the output of the inverter 400 is output. Blocking forcibly stops reverse transmission to the power system 100.

In addition, when the reverse power control unit 430 determines that reverse power transmission is not detected by the reverse power relay 510, the maximum power point tracking control unit 420 performs the maximum power point following function in a normal state. Control in the following mode (S500). That is, the maximum power point following controller 420 controls to follow the first operating point MPP1 that produces the maximum power in the normal state in the maximum power point following mode S500.

As described above, the operation mode of the inverter 400 is classified into an output control mode, an output cutoff mode, a maximum power point following mode, etc. according to whether the reverse power transmission to the power system 100 occurs and the magnitude of the reverse power amount. Control to perform the operation, and in the output adjustment mode by controlling the output power of the inverter 400 by adjusting the position of the operating point in the maximum power point tracking control unit 420, thereby improving the utilization efficiency of the solar power generation system to the maximum You can.

Meanwhile, the power factor information measured through the electricity meter 520 is transmitted to the power factor controller 440 installed in the inverter 400 through a communication means (S600).

The power factor controller 440 compares the power factor information transmitted from the electricity meter 520 with the preset target power factor to determine whether to control the power factor of the inverter 400 (S700).

If it is determined that the power factor measured by the electricity meter 520 is out of the preset target power factor range, the power factor controller 440 controls the output of the power converter 410 so that the power factor of the customer falls within the target power factor range ( S800). For example, the target power factor may be set to about 80% to 100%.

5 is a view showing an example of parallel operation of the conventional load and photovoltaic power generation in the consumer. In FIG. 5, the conventional load is a case where the power of 105 kVA is used at a power factor of 95% (PF), and a 50 kVA photovoltaic module having a power factor of 100% is added thereto.

Referring to FIG. 5, when a conventional load is operated at a power of 105 kVA and a power factor of 95% without the connection of photovoltaic power generation, a power factor of 95% is measured at a customer's weighing point, and the load side effective power (Psw) is 105 kVA *. 0.95 = 100kW and reactive power (Psvar) is calculated as 32kVar. In addition, a 50kVA photovoltaic module that maintains a power factor of 100% is generated by active power (Prw) of 50kVA * 100% = 50kW and reactive power (Prvar) of 0kVar by a general inverter.

On the other hand, when the power system and the photovoltaic module are operated in parallel, the total active power at the consumer weighing point is 100kW-50kW = 50kW and the reactive power is 32kVar without change, so the total apparent power is sqrt (50 * 50 + 32 * 32) = 60 kVA, whereby the power factor of the consumer metering point is 50/60 = 83%. As such, it can be seen that the power factor decreases from 95% to 83% under the same conditions by the installation of the photovoltaic module.

Therefore, in this embodiment, in order to improve the power factor is lowered in parallel operation of the photovoltaic module, the power factor of the customer is measured in real time through the electricity meter 520 and transmitted to the power factor controller 440 in the inverter 400. In addition, the power factor controller 440 compares the measured power factor information with the target power factor to control the operation of the inverter 400 to maintain an optimum power factor.

6 is a diagram illustrating an example of a power factor control method according to the present invention.

3 and 6, the power factor correction of the inverter 400 is based on the power factor information transmitted from the electricity meter 520, in particular, the effective power amount and the reactive power amount, and the active power of the power output from the power converter 440. The power factor may be controlled through at least one control of the reactive power.

For example, if the active power Prw of the output of the inverter 400 is maintained at 50 kW and the reactive power Prvar is controlled to generate -20 kVar according to the amount of active power and reactive power transmitted to the power factor controller 440. Since the active power at the consumer metering point is 100kW-50kW = 50kW and the reactive power is 32kVar-20kVar = 12kVar, the total apparent power is changed to sqrt (50 * 50 + 12 * 12) = 51.5kVA. Therefore, the power factor is 50 / 51.5 = 97%, which shows that the power factor is remarkably improved.

Since the power factor at the customer measurement point changes with the change of load and also with the amount of photovoltaic generation, it is necessary to measure the actual change in real time. In addition, the power factor may be calculated by measuring the amount of active power and reactive power and calculating the power factor based on the phase angle.

As described above, the electricity meter 520 transmits the measured real power amount and the reactive power amount information to the inverter 400 in real time, and the inverter 400 calculates the target active power amount calculated by the transmitted active power amount and the reactive power amount and the target power factor. And by forming a PID loop with the target reactive power amount, by controlling the amount of self-generation, that is, the amount of active power and reactive power to control the power output of the advance or the ground it is possible to operate the photovoltaic power generation system at the optimum power factor.

1 and 2, the inverter 400 may further include a wireless communication unit 450 for wireless communication with the wireless terminal 600. The wireless communication unit 450 monitors the wireless communication network including monitoring information including the reverse transmission power amount information measured by the reverse power relay 510, the power factor information measured by the power meter 520, and information on the operation state of the inverter 400. Transmit to wireless terminal 600 through.

The wireless terminal 600 includes a control application for receiving the monitoring information transmitted from the inverter 400 to monitor the operating state of the photovoltaic device and to control the operation of the inverter 400. The wireless terminal 600 may be a smartphone owned by an administrator or a wireless communication terminal provided separately, and may display monitoring information through a display unit provided on its own, and operate the input unit provided on the manager. Can select the type of information you want to monitor, or change its settings and command control of its operation.

The control application is software installed in the wireless terminal 600. The control application displays information on the display of the wireless terminal 600 to monitor an operation state of an individual component of the solar power generator and displays the information. It provides a visual interface that allows selection, change of settings, and motion control commands. Therefore, since the manager can remotely monitor the operation status and setting information of the solar cell apparatus, and input the setting change and operation control commands to operate wirelessly, the administrator has conventionally installed the controller of the solar cell apparatus To eliminate the inconvenience of having to monitor and operate the power plant.

On the other hand, the configuration of the inverter 400, the detection unit 500, etc. may be installed in the connection panel, the camera device for photographing the environmental state inside the connection panel may be installed in the connection panel. The camera device photographs whether dust or water is present in the access panel and transmits the photographed image to the wireless terminal 600. Therefore, the manager may monitor the state inside the connection panel through the wireless terminal 600 and perform monitoring such as fire prevention due to dust or water.

In the detailed description of the present invention described above with reference to the preferred embodiments of the present invention, those skilled in the art or those skilled in the art having ordinary skill in the art will be described in the claims to be described later It will be understood that various modifications and variations can be made in the present invention without departing from the scope of the present invention.

100: power system 200: load
300: solar power module 400: inverter
410: power conversion unit 420: maximum power point tracking control unit
430: power transmission control unit 440: power factor control unit
450: wireless communication unit 500: detection unit
510: reverse power relay 520: power meter
600: wireless terminal

Claims (6)

In the wireless sensing system of the grid-connected photovoltaic device for supplying power to the customer in connection with the power system,
Solar power generation module for generating direct current power by converting solar energy into electrical energy;
An inverter for converting DC power output from the solar power module into AC power;
A detector configured to measure the amount of reverse transmission power and the power factor of the customer to be reversely transmitted from the inverter to the power system and transmit the measured power factor to the inverter; And
It includes a wireless terminal for monitoring the operation state of the photovoltaic device and control the operation of the inverter based on the monitoring information transmitted from the inverter via wireless communication,
The detection unit includes a reverse power relay for measuring the amount of reverse transmission power transmitted back to the power system from the inverter, and a power meter for measuring the power factor of the customer,
The inverter,
A power converter converting DC power output from the solar power module into AC power;
A maximum power point following control unit controlling the output power from the solar power module to be operated at an operating point producing maximum power;
A reverse transmission controller configured to control power reversely transmitted to the power system through control of the maximum power point following controller based on reverse transmission information transmitted from the reverse power relay;
A power factor controller for controlling the power factor of the customer through the control of the power converter based on the power factor information transmitted from the electricity meter; And
It includes a wireless communication unit for wireless communication with the wireless terminal,
The reverse transmission control unit
When the amount of reverse transmission power measured by the reverse power relay is less than or equal to the set threshold capacity, the control unit controls the reverse transmission control mode to adjust the output power of the inverter,
When the amount of reverse transmission power measured by the reverse power relay exceeds the limit capacity, it is controlled to an output interruption mode that blocks the output of the inverter,
If no reverse transmission is detected in the reverse power relay, the grid-connected photovoltaic device characterized in that the maximum power point tracking control unit controls the maximum power point following mode to perform the maximum power point tracking function in a normal state. Wireless detection system. delete delete The method of claim 1,
The reverse transmission control unit in the reverse transmission control mode,
The operation point followed by the maximum power point tracking control unit is controlled to operate at a second operating point adjusted by the amount of power corresponding to the measured reverse transmission power amount, instead of the first operating point that produces the maximum power in a normal state. Wireless sensing system of grid-connected photovoltaic device. The method of claim 1,
The power factor controller
When the power factor measured by the electricity meter is compared with a predetermined target power factor, and it is determined that the measured power factor is out of the range of the target power factor, the power converter outputs the power factor so that the power factor is within the range of the target power factor. A wireless sensing system of a grid-connected photovoltaic device, characterized in that the power factor is controlled by controlling at least one of the active power and the reactive power. The method of claim 1,
The wireless terminal includes a control application for monitoring the operating state of the photovoltaic device and control the operation of the inverter wireless sensing system of a grid-connected photovoltaic device.

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