WO2015170904A1

WO2015170904A1 - Remote diagnostic system and method for photovoltaic module

Info

Publication number: WO2015170904A1
Application number: PCT/KR2015/004585
Authority: WO
Inventors: 조경호; 김정렬; 조창익
Original assignee: (주)알티에스에너지
Priority date: 2014-05-08
Filing date: 2015-05-08
Publication date: 2015-11-12
Also published as: KR20150127978A; KR101669847B1

Abstract

A remote diagnostic system for a photovoltaic module, according to one embodiment of the present invention, comprises: one or more micro-converters for detecting and transmitting state information of a photovoltaic module; a repeater for relaying the state information transmitted from the micro-converters; and a monitoring server which calculates a current-voltage characteristic curve and a power-voltage characteristic curve of the photovoltaic module on the basis of the state information received through the repeater, and which provides the calculated curves as diagnostic information on the photovoltaic module.

Description

Remote diagnosis system and method of solar power module

The present invention relates to a remote diagnosis of a photovoltaic module, and more particularly, to a remote diagnosis system of a photovoltaic module for enabling easy measurement and diagnosis of electrical characteristics of a photovoltaic module at a remote location. It is about.

Due to global warming, carbon emissions are becoming a global problem, and as a result, the development and application of renewable energy is continuously increasing as part of efforts to reduce greenhouse gases worldwide.

In particular, in the case of photovoltaic power generation, high-efficiency products are being developed through various types of cell processing technologies, and application as alternative energy sources is expected to proceed in large scale in the future. Therefore, the diagnostic demand for photovoltaic facilities will increase, and there is a need for a technique for solving potential factors that can lead to improved efficiency and failure through highly reliable diagnosis results.

Various sensors, measuring equipment and techniques for diagnosing photovoltaic power generation facilities have been performed in various forms for a long time. Accurate and reliable diagnosis of photovoltaic equipment requires simultaneous acquisition and analysis of data from multiple measuring points. In particular, in order to diagnose the power generation status of the photovoltaic module in each photovoltaic facility, each module must be equipped with a sensor module for measuring voltage, current, temperature, etc. and separately provided with a communication module for transmitting the same. do.

In recent years, photovoltaic power generation equipment uses a voltage regulator called a micro-converter to eliminate the power generation caused by mismatches between modules within a string and power deviation between strings. Many photovoltaic power generation systems installed in the installation. If a micro-converter is mounted on the solar module to increase the amount of power generated, it is possible to increase the amount of power generated by the photovoltaic plant at a small additional cost.

In order to diagnose photovoltaic power generation facilities, Korean Patent Publication No. 2012-0100184 (hereinafter referred to as “Prior Art”) monitors performance by measuring voltage and current values of a solar array, and detects failure of the solar array. Although a remote monitoring system is disclosed, a voltage sensor and a current sensor are used separately and only the instantaneous current and voltage values are used to determine whether a solar array has failed. Therefore, the prior art does not easily determine the temporary deterioration of the generation of the solar array due to the shadow or foreign matter and whether the actual solar array is broken.

One embodiment of the present invention is to accurately diagnose the failure state of the photovoltaic module remotely.

One embodiment of the present invention is for diagnosing a fault state of a solar module without affecting the power generation state of the solar cell module.

In addition to the above object, embodiments according to the present invention can be used to achieve other objects not specifically mentioned.

According to an embodiment of the present invention, a remote diagnosis system for a photovoltaic module includes one or more micro converters for detecting and transmitting state information of a photovoltaic module, a repeater for relaying state information transmitted from the micro converter, and the And a monitoring server configured to calculate current-voltage characteristic curves and power-voltage characteristic curves of the photovoltaic module based on the state information received through the repeater and provide the diagnostic information of the photovoltaic module.

Here, when the micro-converter follows the maximum power point of the photovoltaic module and receives a diagnostic command, the micro-converter stops following the maximum power point and performs a full scan function to perform the full scan function from the lowest voltage to the open voltage. The voltage value and the current value corresponding to the voltage value may be transmitted as state information.

The micro-converter may also follow the maximum power point of the photovoltaic module after transmitting the state information by performing the full scan function.

The monitoring server may calculate the current-voltage characteristic curve and the power-voltage characteristic curve based on the voltage value and the current value.

In addition, the monitoring server may further include a terminal for requesting diagnosis of a specific solar module and displaying diagnostic information provided from the monitoring server on a screen.

In addition, the monitoring server may diagnose the failure of the photovoltaic module by comparing a pre-stored reference characteristic curve with the current-voltage characteristic curve and the power-voltage characteristic curve.

In a remote diagnosis method of a solar power module according to an embodiment of the present invention, the micro-converter follows the maximum power point of the photovoltaic module, when the micro-converter receives a diagnostic command, the maximum power point tracking Stopping, the micro-converter performs a full scan function to transmit a voltage value from the lowest voltage to the open voltage and a current value corresponding to the voltage value as status information, the micro-converter performs a full scan function Following the maximum power point of the photovoltaic module after transmitting the state information, and the monitoring server calculating a current-voltage characteristic curve and a power-voltage characteristic curve based on the voltage value and the current value. And failure of the photovoltaic module using the current-voltage characteristic curve and the power-voltage characteristic curve. A and a step of diagnosis.

Here, the micro-converter may further include following the maximum power point of the photovoltaic module after transmitting the state information by performing the full scan function.

One embodiment of the present invention can accurately diagnose the failure state of the photovoltaic module remotely without affecting the power generation state of the photovoltaic module.

1 is a schematic configuration diagram of a photovoltaic power generation system equipped with a micro-converter 100.

2 is a block diagram of a remote diagnosis system 1 of a photovoltaic module according to one embodiment of the invention.

3 is a block diagram of a micro-converter 100 according to an embodiment of the present invention.

4 is an example of a monitoring screen showing whether the photovoltaic module 10 is abnormal according to an embodiment of the present invention.

5 is a flowchart of a method of operating the micro-converter 100 according to an embodiment of the present invention.

6 is an example of the current-voltage characteristic curve (upper graph) and the power-voltage characteristic curve (lower graph) of the photovoltaic module 10 according to the change in solar radiation.

7 is an example of the current-voltage characteristic curve (upper graph) and the power-voltage characteristic curve (lower graph) of the photovoltaic module 10 according to temperature change.

8 is an example of the current-voltage and power-voltage characteristic curves according to the presence of shadows in the photovoltaic module 10.

9 is an example of a power-voltage characteristic curve (upper graph) and a current-voltage characteristic curve (lower graph) of the photovoltaic module 10.

DETAILED DESCRIPTION Embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily practice the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. The drawings and description are to be regarded as illustrative in nature and not restrictive. Like reference numerals designate like elements throughout the specification. In addition, in the case of well-known technology, a detailed description thereof will be omitted.

When any part of the specification is to "include" any component, this means that it may further include other components, except to exclude other components unless otherwise stated. In addition, the term "... unit" described in the specification means a unit for processing at least one function or operation, which may be implemented in hardware or software or a combination of hardware and software.

Hereinafter, a remote diagnosis system of a solar power module according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic configuration diagram of a photovoltaic power generation system equipped with a micro-converter 100. The photovoltaic power generation system equipped with the micro-converter 100 includes a photovoltaic array 200, an inverter 300, and a meter 400, in which a plurality of photovoltaic modules 10A to 10N (hereinafter referred to as 10) are arranged. ), And an electrical grid.

In the photovoltaic power generation system equipped with the micro converter 100 configured as described above, light energy is converted into electrical energy through the photovoltaic array 200 in which a plurality of photovoltaic modules 10A to 10N are arranged to produce electricity. The generated electricity is converted into AC power through the inverter 300, and power is supplied to the load 600 requiring the AC power. In addition, the produced power is measured in the meter 400, and is transmitted to an electric handling company through an electric grid 500 which is a power grid.

2 is a block diagram of a remote diagnosis system 1 of a photovoltaic module according to an embodiment of the present invention, Figure 3 is a block diagram of a micro-converter 100 according to an embodiment of the present invention.

The remote diagnosis system 1 of the photovoltaic module includes a micro converter 100, a repeater 700, a monitoring server 800, and a terminal 900.

The micro-converter 100 detects state information for diagnosing electrical characteristics of the photovoltaic module 10 constituting the photovoltaic power generation facility, converts the detected state information into communication data, and outputs the converted state information. (10) serves to compensate for power deviation between or strings. The micro-converter 100 may be installed in a one-to-one correspondence with the photovoltaic module 10. Although only one micro-converter 100 is illustrated in FIG. 2, the number of photovoltaic modules 10 constituting the actual solar array 200 is preferably provided.

As shown in FIG. 3, the micro-converter 100 includes a resistor 101, first and second switches S1 and S2 for changing a voltage path, a plurality of diodes D1 and D2, and an inductor 102. , A current detector 103, a voltage detector 104, a temperature detector 105, a controller 106 for outputting status information of the photovoltaic module 10, and a wireless module 107.

When status information is requested through the monitoring server 800, the controller 106 performs a full scan function. The full scan function is a function of maintaining the voltage of the photovoltaic module 10 at a desired value regardless of the output voltage by using the DC-DC converter function of the controller 106. When the controller 106 performs the full scan function, the micro-converter 100 temporarily stops following the maximum power point and switches to the diagnostic mode to change the voltage of the photovoltaic module 10 from the lowest voltage to the open voltage. You can scan. In addition, the micro-converter 100 may measure current while scanning from the lowest voltage to the open voltage, and may read the voltage and current values and output them as status information.

The wireless module 107 is connected to the controller 106 to transmit status information to the monitoring server 800 or to transmit command information received from the monitoring server 800 to the controller 106.

The repeater 700 collects state information output from each of the plurality of micro-converters 100 and plays a role of relaying through communication. The repeater 700 may use various communication relay devices. For example, the repeater 100 may be implemented as a gateway or a Wi-Fi access point (AP).

The monitoring server 800 calculates current-voltage and power-voltage characteristic curves of the photovoltaic module 10 based on the state information relayed through the repeater 700 as diagnostic information of the photovoltaic module 10. Serves to provide.

The monitoring server 800 calculates power based on the voltage and current values received from the micro-converter 100, and then calculates current-voltage and power-voltage curves, which are electrical characteristics of the photovoltaic module 10. . The monitoring server 800 may be implemented by a general personal computer, and may include a communication module. The monitoring server 800 may communicate with the relay 700 and the terminal 900 through a communication module.

The terminal 900 requests the diagnosis of the specific photovoltaic module 10 to the monitoring server 800, and serves to display the diagnostic information of the provided photovoltaic module 10 on the screen so that the user can check the diagnosis information. The terminal 900 may be implemented as a general personal computer, a smart phone, a tablet PC used by the administrator.

Referring to the detailed operation of the remote diagnosis system 1 of the photovoltaic module according to an embodiment of the present invention configured as described above are as follows.

4 is an example of a monitoring screen showing whether the photovoltaic module 10 is abnormal according to an embodiment of the present invention, and FIG. 5 is a method of operating the micro-converter 100 according to an embodiment of the present invention. Flowchart.

First, the photovoltaic module 10 installed on the site converts light energy generated from sunlight into electrical energy and outputs the electrical energy. The monitoring server 800 collects power values output from each photovoltaic module 10 and informs an administrator of an abnormality. For example, the monitoring server 800 displays a hazard indication on the photovoltaic module 10 having an output power value smaller than that of another photovoltaic module 10 through a monitoring screen as shown in FIG. 4. can do.

When the administrator or the monitoring server 800 confirming the danger indication through the monitoring screen requests remote diagnosis for the photovoltaic module 10, the micro-converter 100 installed in the photovoltaic module 10 is remoted. The data for diagnosis is collected and transmitted to the monitoring server 800.

In addition, the monitoring server 800 or the administrator may request a remote diagnosis for the photovoltaic module 10 suspected of a failure without checking the danger indication through the monitoring screen.

Looking at the operation method of the micro-converter 100 in detail with reference to Figure 5, the micro-converter 100 installed in the photovoltaic module 10 is the maximum power point tracking in the normal mode to increase power generation efficiency (Maximum Power Point Tracking, MPPT) (S111). When receiving a remote diagnosis command from the monitoring server (800) (S112), the micro-converter 100 stops following the maximum power point (S113), changes from the normal mode to the diagnostic mode and performs a full scan function (S114).

The full scan function means applying the voltage of the photovoltaic module 10 from the lowest voltage to the open voltage in the PI (Proportional Integral) control mode and measuring the current value and the voltage value at that time.

After performing the full scan function, the micro-converter 100 transmits the measurement data stored through the scan to the monitoring server 800 through the repeater 700 (S115). Then, the micro-converter 100 returns to the normal mode from the diagnostic mode and restarts the maximum power point following (S116).

The operation of the micro-converter 100 may be performed by the controller 106. In general, the time for performing the full scan may be several tens of ms, and thus the micro converter 100 may not affect the power generation state of the photovoltaic module 10.

When performing the full scan function to transmit the measurement data, the micro-converter 100 transmits the current value measured through the current detector 103, the voltage value measured through the voltage detector 104, and the temperature detector 105. The measured temperature value may be transmitted to the monitoring server 800.

The monitoring server 800 uses the measurement data which is the state information of the photovoltaic module 10 received from the micro-converter 100 to display the current-voltage and power-voltage characteristic curves of the photovoltaic module 10. It can calculate as shown in FIG.

6 is an example of the current-voltage characteristic curve (upper graph) and the power-voltage characteristic curve (lower graph) of the photovoltaic module 10 according to the change in solar radiation. 7 is an example of the current-voltage characteristic curve (upper graph) and the power-voltage characteristic curve (lower graph) of the photovoltaic module 10 according to temperature change. 8 is an example of a current-voltage and power-voltage characteristic curve according to the presence of a shadow in the photovoltaic module 10, and FIG. 9 is a power-voltage characteristic curve (upper graph) of the photovoltaic module 10 and FIG. An example of a current-voltage characteristic curve (lower graph) is shown.

As shown in FIG. 6, the current-voltage and power-voltage characteristic curves calculated by the monitoring server 800 may vary according to the amount of insolation. If the amount of insolation is large, the current and power values corresponding to the same voltage value are larger than that in the case of the insolation amount, and thus the characteristic curve of FIG. 6 may be calculated.

As shown in FIG. 7, the current-voltage and power-voltage characteristic curves calculated by the monitoring server 800 may vary according to temperature, and the maximum power value calculated when the temperature is low is larger than when the temperature is high. A characteristic curve like 7 can be calculated.

As shown in FIG. 6 and FIG. 7, the photovoltaic module 10 generates different powers depending on the amount of solar radiation and temperature or the voltage applied.

FIG. 8 shows the current of the photovoltaic module 10 calculated by the monitoring server 800 when the sub-module is affected by shadows, dust, foreign matters, etc. inside the photovoltaic module 10. The voltage and power-voltage characteristic curves are shown. The photovoltaic module 10 is composed of sub-modules, and if any of the sub-modules have a shadow, foreign matter or deterioration occurs in the sub-module, the peaks of the power-voltage curve are shown in FIG. 8. There are a plurality.

Therefore, the monitoring server 800 calculates a current-voltage characteristic curve and a power-voltage characteristic curve of the photovoltaic module 10 based on various measurement data of the photovoltaic module 10 that is input, and the manager The display may be displayed on the screen of the monitoring server 800 or may be transmitted to the terminal 900.

The manager checks the current-voltage characteristic curve and the power-voltage characteristic curve of the photovoltaic module 10 displayed on the screen, and determines the electrical characteristics such as failure or abnormality of the photovoltaic module 10. It is possible to accurately diagnose the state of the photovoltaic module 10.

For example, as shown in FIG. 9, when a power-voltage characteristic curve having peaks at two locations is identified, the manager or the monitoring server 800 may predict that one submodule is buried with a shadowed area or a foreign object. Can be.

The monitoring server 800 may automatically diagnose the failure of the photovoltaic module 10 by comparing the calculated characteristic curve with a pre-stored reference characteristic curve, and the monitoring server 800 may detect the photovoltaic module. In case of diagnosing failure of 10), it can inform the administrator through the monitoring screen. In addition, the manager may directly check the characteristic curve, and diagnose the failure of the photovoltaic module 10 by referring to a manual or the like.

Therefore, the manager or monitoring server 800 may accurately determine whether the photovoltaic module 10 has failed based on the power-voltage and current-voltage characteristic curves calculated remotely. In the case of diagnosing the failure of the photovoltaic module 10 by using the measuring equipment of the photovoltaic module 10 in the field, the photovoltaic module 10 should be separated from the power generation system, so whether the failure occurs in the power generation situation Cannot be diagnosed. According to one embodiment of the present invention, the micro-converter 100 performs a full scan in a very short time to diagnose a failure without affecting power generation even in a power generation situation.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

Claims

At least one micro-converter for detecting and transmitting status information of the photovoltaic module

A repeater for relaying status information transmitted from the micro-converter, and

The monitoring server calculates the current-voltage characteristic curve and the power-voltage characteristic curve of the photovoltaic module based on the state information received through the repeater and provides the diagnostic information of the photovoltaic module.

Remote diagnosis system of a photovoltaic module comprising a.
In claim 1,

The micro converter,

Following the maximum power point of the photovoltaic module,

In the case of receiving a diagnostic command, stopping the maximum power point tracking and performing a full scan function to transmit a voltage value from the lowest voltage to the open voltage and a current value corresponding to the voltage value as status information. Remote diagnosis system of photovoltaic module.
In claim 2,

The micro-converter performs the full scan function to transmit the state information and then again follows the maximum power point of the photovoltaic module.
In claim 2,

And the monitoring server calculates the current-voltage characteristic curve and the power-voltage characteristic curve based on the voltage value and the current value.
In claim 1,

Remote monitoring system for a photovoltaic module further comprising a terminal for requesting the monitoring server diagnosis of a specific photovoltaic module, and displaying the diagnostic information provided from the monitoring server on the screen.
In claim 1,

The monitoring server is a remote diagnosis system of the photovoltaic module for diagnosing the failure of the photovoltaic module by comparing the stored reference characteristic curve, the current-voltage characteristic curve and the power-voltage characteristic curve.
The micro converter follows the maximum power point of the solar power module,

When the micro-converter receives a diagnostic command, stopping the maximum power point following,

Performing a full scan function by the micro converter to transmit a voltage value from a lowest voltage to an open voltage and a current value corresponding to the voltage value as state information;

After the micro-converter performs the full scan function to transmit the state information, again following the maximum power point of the photovoltaic module;

The monitoring server calculating a current-voltage characteristic curve and a power-voltage characteristic curve based on the voltage value and the current value, and

Diagnosing the failure of the photovoltaic module using the current-voltage characteristic curve and the power-voltage characteristic curve

Remote diagnostic method of the photovoltaic module comprising a.
In claim 7,

And after the micro-converter transmits the state information by performing the full scan function, tracking the maximum power point of the photovoltaic module again.