KR20110110938A - A solar generation system for managing photovoltaic modules separately - Google Patents

Abstract

A photovoltaic power generation system is provided, wherein the photovoltaic power generation system includes a plurality of photovoltaic modules and a system manager that monitors and controls the plurality of photovoltaic modules. Each of the plurality of photovoltaic modules includes a solar cell module that generates direct current power using sunlight, a small capacity inverter that converts the generated direct current power into alternating current power, and transfers the generated direct current power to a commercial power system, and the solar cell module. And a communication module for transmitting the monitoring information and the monitoring information of the small-capacity inverter to the system manager and receiving a control signal from the system manager.

Description

Photovoltaic system with individual management function of solar cell module {A SOLAR GENERATION SYSTEM FOR MANAGING PHOTOVOLTAIC MODULES SEPARATELY}

The present invention relates to a photovoltaic power generation system, and in particular, by connecting a separate small capacity inverter to each solar cell module to transfer AC power to the commercial power system in a distributed link structure, each solar cell module and The present invention relates to a solar power system that monitors and processes a large number of monitoring information related to a small capacity inverter in real time.

Conventional photovoltaic power generation system is connected to the solar cell module in order to convert the solar energy into electrical energy to form an array and grid connection for converting the DC power produced in the solar cell array to the AC power applicable to the transmission line network It is equipped with a type inverter.

On the other hand, since the characteristics of the solar cell change depending on the surrounding environment such as solar radiation and temperature, the output voltage and output current also change according to the surrounding environment, and thus the voltage and current generated in the solar cell have a nonlinear relationship. Due to this characteristic, when the solar cell modules are connected in series or in parallel, there is a problem in terms of efficiency because it produces different maximum power depending on the surrounding environment.

In addition, when several solar modules are connected in series or in parallel, when the clouds pass or the shade of the solar modules is caused by nearby objects, the maximum power can be generated according to the voltage and current of the solar modules configured in the array form. The points you have will be different. In addition, the maximum power generation point may vary depending on the type of solar cell, such as crystalline solar cell, amorphous solar cell, fuel-sensitized solar cell, and even the same type of solar cell module may have different power generation points due to manufacturing error during production.

In particular, when the solar cell modules are connected in series, the module in which the lowest current flows determines the total current value, and when connected in parallel, the lowest voltage determines the total voltage. Because of this phenomenon, although a plurality of modules have different power generation points, power generation points are determined by one module, and thus the efficiency of the entire photovoltaic power generation system may be reduced. In addition, when the voltage of the solar cell module falls below the inverter operating voltage, the inverter may be turned off and there may be a loss of generated power. In some cases, the failure of the inverter may cause a loss of the entire generated power.

In addition, Tongsan's power generation monitoring system receives information from the inverter via RS-485 or the Internet, calculates it, displays only the current generation amount and accumulated generation amount, and displays the surrounding environment (temperature, humidity, solar radiation, etc.). Since the monitoring system monitors the entire photovoltaic power generation system, it is difficult to find a problem because individual management is impossible when an abnormality occurs.

On the other hand the limitations and disadvantages of conventional and traditional approaches will become more apparent to those skilled in the art through comparison with the systems according to the invention as described in the remainder of the invention with reference to the drawings.

The present invention has been made from the problems of the prior art to increase the power generation efficiency by producing power by connecting each small-capacity inverter to a plurality of solar cell modules. In another aspect, the present invention is to monitor the individual solar cell module in the management of the entire power generation system to efficiently manage and maintain the photovoltaic power generation system.

According to one aspect of the invention, a solar power system comprises a plurality of solar power modules; And a system manager for monitoring and controlling the plurality of photovoltaic modules, wherein each of the plurality of photovoltaic modules comprises: a solar cell module generating direct current power using sunlight; A small capacity inverter converting the generated DC power into AC power and transferring the same to a commercial power system; And a communication module connected to the solar cell module and the small capacity inverter to transmit monitoring information of the solar cell module and monitoring information of the small capacity inverter to the system manager and to receive a control signal from the system manager. do.

Preferably, each of the plurality of photovoltaic modules further includes a monitoring module for generating the monitoring information of the solar cell module, and the monitoring information of the small capacity inverter.

Preferably, the system manager further includes a control signal module for generating a control signal for operating and stopping the small-capacity inverter in each photovoltaic module and transmitting it to the communication module.

Preferably, the system manager is configured to process the monitoring information of the solar cell module and the monitoring information of the small capacity inverter received from each of the photovoltaic modules, thereby real-time operation of each of the photovoltaic modules. The state of the power system and the total amount of photovoltaic power generation are determined. In addition, determine the environment (temperature, humidity, solar radiation, etc.).

Preferably, the photovoltaic power generation system includes at least one router, and the at least one router receives the monitoring information of the solar cell module and the monitoring information of the small capacity inverter from the communication module and transmits the monitoring information to the system manager. The control signal is received from the system manager and transmitted to the communication module. The router extends the communication distance between the communication module and the system manager.

Preferably, the system management unit includes a coordinator to collect information transmitted through the router and can also be confirmed from the outside through the system management unit and the Internet. The control signal may be transmitted to the communication module of the small capacity inverter through the system manager or the external internet.

Preferably, the small capacity inverters can be connected to a plurality of solar cell modules, respectively.

Advantageously, said solar power system collects alternating current power by alternatingly connecting respective small capacity inverters in said plurality of photovoltaic modules.

Transfer the collected AC power to the commercial power system.

Preferably, each of the plurality of small capacity inverters in the plurality of photovoltaic modules individually delivers AC power to a commercial power system.

These and other advantages, aspects and novel features of the present invention will become more fully understood from the following detailed description and drawings, together with the details of the embodiments illustrated in this regard. .

According to the present invention, each of the plurality of solar cell modules can be controlled separately, thereby increasing power generation efficiency. In addition, according to the present invention it is possible to monitor the individual solar cell module in the management of the entire power generation system it is possible to more efficiently manage and maintain the solar power generation system.

1 is a schematic view showing a conventional solar power system.
2 is a schematic diagram illustrating a photovoltaic power generation system according to an embodiment of the present invention.
3 is a block diagram of a small capacity inverter according to an embodiment of the present invention.
4 is a view illustrating the small-capacity inverter of FIG. 3 in the photovoltaic power generation system of FIG. 2.
5A to 5C are views illustrating an exemplary combination of a solar cell module and an inverter.
6 is a flowchart illustrating an operation of a system manager according to an exemplary embodiment.

Hereinafter, with reference to the accompanying drawings will be described in detail.

1 is a schematic view showing a conventional solar power system.

Referring to FIG. 1, a plurality of photovoltaic (PV) modules 101a-101i, an inverter 103, a load 105, and a commercial power system 107 are shown.

The plurality of solar cell modules 101a to 101i are connected in series / parallel to each other to form a solar cell module array 101. Meanwhile, although nine solar cell modules are illustrated in FIG. 1, this is only an example for description, and in general, any number of solar cell modules may be connected to each other. Each of the plurality of solar cell modules 101a to 101i absorbs sunlight to generate direct current power.

The inverter 103 is connected to the solar cell module array 101 to receive DC power generated by the plurality of solar cell modules 101a to 101i, and converts the received DC power into AC power to provide a commercial power system ( 107).

On the other hand, since the plurality of solar cell modules (101a to 101i) are connected to each other in series / parallel, the operation of the individual module can affect other modules. For example, if the solar cell module 101a fails and has a substantially infinite resistance value, the power generated by the solar cell modules 101d and 101g connected in series with the solar cell module 101a is converted into an inverter ( Not delivered to 103, and subsequent power generation results in the same results as those produced only in the solar cell modules except for the solar cell modules 101a, 101d, 101g.

In addition, for example, when the power produced by the solar cell module array 101 does not reach the normal yield, it may be determined that at least one module of the solar cell module array 101 is abnormal. However, even in this case, it is necessary to investigate the individual modules to find out which module is abnormal, which may cause the efficiency of the entire power generation system to be reduced.

2 is a schematic diagram illustrating a photovoltaic power generation system 200 according to an embodiment of the present invention.

2, a plurality of solar cell modules 210 ₁ , 210 ₂ , 210 ₃ ,..., 210 _n-1 , 210 _n , and a plurality of small capacity inverters 220 ₁ , 220 ₂ , 220 having RF modules. ₃ ,..., 220 _n-1 , 220 _n ), a router 230 _a , 230 _b ) for extending the RF communication distance, and a system manager 250 for collecting and managing information. The system manager is located with a coordinator 240 for collecting information and transmitting the data to the system management server. In addition, the coordinator 240 can be remotely controlled through the Internet.

The solar cell modules 210 ₁ , 210 ₂ , 210 ₃ ,..., 210 _n-1 , 210 _n generate the direct current power by absorbing sunlight.

Small capacity inverters (220 ₁ , 220 ₂ , 220 ₃ , ..., 220 _n-1 , 220 _n ) are solar modules 210 ₁ , 210 ₂ , 210 ₃ , ..., 210 _n-1 , 210 _n DC power generated in converts into AC power and delivers it to commercial power system.

Meanwhile, FIG. 2 will be described in more detail with reference to FIG. 4.

3 is a block diagram of a small capacity inverter according to an embodiment of the present invention.

Referring to FIG. 3, a solar cell module 310, a small capacity inverter 320, and a commercial power system 330 are shown.

The small-capacity inverter 320 includes a first monitoring module 321, a DC-DC power converter 322, a DC-AC power converter 323, a second monitoring module 324, a controller 325, and a communication module. 326.

The solar cell module 310 absorbs sunlight to generate direct current power.

The small capacity inverter 320 receives DC power output from the solar cell module 310 and converts the DC power into AC power. In one embodiment, AC power generated from the small-capacity inverter 320 and the second inverter (not shown) may be linked in parallel through the distribution panel and transferred to the commercial power system. In another embodiment, the AC power output from the small capacity inverter 320 may be connected to an AC input terminal of a second inverter (not shown), whereby the second inverter internally converts AC power and an inverter ( AC power obtained from 320 may be parallel linked.

In the first monitoring module 321 and the second monitoring module 324, the first monitoring module 321 is disposed between the solar cell module 310 and the DC-DC power converter 322, and the DC-AC power supply. Although the second monitoring module 324 is illustrated as being disposed between the conversion unit 323 and the commercial power system 330, those skilled in the art can change the arrangement as many as possible, and furthermore, the first monitoring module 321. And one supervisory module may be arranged which may replace the function of the second supervisory module 324. The first monitoring module 321 may generate the monitoring information of the solar cell module 310 (eg, the amount of power generated by the solar cell module 310), and the second monitoring module 324 may be configured as the small capacity inverter 320. Monitoring information (eg, the amount of power generated by the small-capacity inverter 320, and the voltage change of the associated commercial power system) may be generated.

The controller 325 may control the first monitoring module 321, the DC-DC power converter 322, the DC-AC power converter 323, and the second monitoring module 324, for example, to start an operation. Or stop it.

The communication module 326 transmits the monitoring information of the solar cell module 310 and the monitoring information of the DC-AC power converter 323 to a system manager (not shown), and also transmits the monitoring information of the solar power module from the system manager. The control signal can be received.

4 is a view illustrating the small-capacity inverter of FIG. 3 in the photovoltaic power generation system of FIG. 2.

4, a plurality of solar cell modules 410 ₁ , 410 ₂ ,..., 410 _n-1 , 410 _n ; 410, a plurality of small capacity inverters 420 ₁ , 420 ₂ , ..., 420 _n-1 , 420 _n ; Collectively, 420, a plurality of routers 430a and 430b, a coordinator 440, and a system manager 450 are shown. Herein, the configuration of the solar cell module 410 ₁ and the small capacity inverter 420 ₁ and the following description thereof will be described with reference to the remaining solar cell modules 410 ₂ ,..., 410 _n-1 , 410 _n and FIG. 4, respectively. The same applies to the remaining small capacity inverters 420 ₂ ,..., 420 _n-1 , 420 _n .

The solar cell module 410 absorbs sunlight to generate power, and in particular, may generate DC power.

The small capacity inverter 420 converts the DC power generated by the solar cell module 410 into AC power and transmits the alternating current to the commercial power system 460. The small capacity inverter 420 includes a first monitoring module 421, a DC-DC power converter 422, a DC-AC power converter 423, a second monitoring module 424, a controller 425, and a communication module. 426, a first monitoring module 321, a DC-DC power converter 322, a DC-AC power converter 323, a second monitoring module 324, and a controller 325 of FIG. 3, respectively. ), And communication module 326.

The communication module 426 transmits the monitoring information of the solar cell module 410 and the monitoring information of the DC-AC power converter 423 to the system manager 450, and further, from the system manager 450, the solar power generation module. Can receive a control signal.

The routers 430a and 430b are positioned in the middle of transmitting the monitoring information of the solar cell module 410 and the monitoring information of the DC-AC power converter 423 from the communication module 426 to the system manager 450. To extend the communication distance. On the contrary, the routers 430a and 430b are located in the middle of receiving a control signal from the system manager 450 and transmitting the control signal to the communication module 426 to extend the communication distance.

The coordinator 440 collects the information of the routers 430a and 430b, transmits the information to the system manager 450, and checks the information from the outside through the Internet. In addition, the system management unit 450 may transmit a signal transmitted to the communication module 426 through a router and can be controlled from the outside through the Internet.

The system manager 450 monitors and controls a plurality of solar cell modules and a small capacity inverter. In one embodiment, the system manager 450 processes the monitoring information of the solar cell module 410 received from the small-capacity inverter 420, and the monitoring information of the DC-AC power converter 423, the solar light in real time It is possible to determine the operating state of the power generation module, the state of the commercial power system, and further determine the total amount of photovoltaic power generation. In one embodiment, the system manager 450 may further include a control signal module (not shown), wherein the control signal module generates a control signal for starting and stopping each of the small capacity inverters. Can transmit to the communication module. Optionally, the system manager 450 may include a separate communication module (not shown), thereby communicating with each solar power module.

On the other hand, the system manager 450 receives the monitoring information of the solar cell module and the monitoring information of the small-capacity inverter from each small-capacity inverter to determine whether there is an abnormality, and thus, if the abnormality occurs, it can be immediately identified.

5A to 5C are views illustrating an exemplary combination of a solar cell module and an inverter.

FIG. 5A illustrates a combination of a conventional photovoltaic (PV) module and an inverter, and a plurality of solar cell modules are coupled to one inverter in parallel. In this case, the characteristics of V _PV1 = V _PV2 = V _PV3 indicate that the operating point of the solar cell module should be operated differently. Due to the structural limitations in actual implementation, each solar cell module has an MPPT (Maximum Power Point Tracking) maximum power point. Can't develop). Therefore, maximum power cannot be delivered to the commercial power system.

5B illustrates a combination of a conventional solar cell module and an inverter, and has a structure in which a plurality of solar cell modules are coupled in series to one inverter. In this case, I _PV1 = I _PV2 = I _PV3 , which indicates that the operating point of the solar cell module should behave differently. Due to its structural limitation, each solar cell module has a maximum power point tracking (MPPT). Can't develop). Therefore, maximum power cannot be delivered to the commercial power system.

Figure 5c shows the combination of the solar cell module and the inverter according to the present invention, each solar cell module has a structure coupled to each small capacity inverter one-to-one. In this case, each solar cell module can deliver the maximum power according to the MPPT to the commercial power system through the small capacity inverter, compared to the conventional serial / parallel connection method.

In addition, each small-capacity inverter is connected to the commercial power system according to the coupling structure as shown in Figure 5c to prevent the reduction of power generation efficiency generated by the serial / parallel connection of the conventional photovoltaic system. That is, in the solar power generation system according to the present invention, since each small capacity inverter is individually connected to the commercial power system, even if there is a failure in a specific solar cell module or a specific small capacity inverter, this does not affect the operation of other small capacity inverters. Therefore, it is possible to further improve the power generation than the photovoltaic system using the conventional serial / parallel connection method.

In addition, as shown in FIG. 5C, by arranging small-capacity inverters in a one-to-one correspondence with each solar cell module, it is possible to expand the power generation capacity of the solar power generation system more flexibly. For example, according to the present invention, a small-capacity inverter can be applied to each solar cell module, and each small-capacity inverter can be directly connected to a commercial power system without being directly or in parallel with each other. In addition, since the number of small-capacity inverters and solar modules are added to directly connect to the commercial power supply system so as to correspond to the desired power generation capacity, the expansion capacity of the power generation capacity is superior to that of the conventional solar power generation system.

6 is a flowchart illustrating an operation of a system manager according to an exemplary embodiment.

Referring to FIG. 6, in operation 610, the system manager may check whether there is an error in the communication system. If an error occurs in the communication system, a warning sound or a display informing of the error may be provided (step 670), and the history of the error occurrence may be recorded (step 680).

In operation 620, the system manager may analyze the monitoring information of the solar cell module received from each photovoltaic module. Subsequently, in step 630, a warning sound or a display may be provided to notify the user of an abnormality in the specific solar cell module (step 670), and the history of abnormal occurrence may be recorded (step 680). ).

In operation 640, the system manager may analyze the small-capacity inverter monitoring information received from each solar power module. Subsequently, in step 650 it may be provided with a beep or display notifying if there is an abnormality in the particular small capacity inverter (step 670) and recording the history of the abnormal occurrence (step 680). .

If the communication system, solar module, and small-capacity inverter are then operating normally, they are displayed at step 660 and the history is stored.

Meanwhile, according to the present invention, the system manager may check the operation state of the individual solar cell module and the operation state of the individual small-capacity inverter, respectively, in steps 630 and 650, whereby a failure occurs in the solar power system. On the other hand, as it is possible to grasp whether there is an abnormality in a specific solar cell module unit and a specific small capacity inverter unit, it is possible to promptly analyze and cope with a failure situation.

Although the present invention has been described with respect to specific embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit of the invention. In addition, various modifications may be made to adapt a particular situation or material requirement to the teachings of the present invention without departing from its spirit. Accordingly, the invention is not to be limited to the specific embodiments disclosed and the invention includes all embodiments falling within the spirit of the appended claims.

Claims (9)

In the solar power system,
Multiple solar power modules; And
It includes a system management unit for monitoring and controlling the plurality of solar power modules,
Each of the plurality of solar power modules,
Solar cell module for generating direct current power using sunlight;
A small capacity inverter converting the generated DC power into AC power and transferring the same to a commercial power system; And
And a communication module for transmitting the monitoring information of the solar cell module and the monitoring information of the small capacity inverter to the system manager and receiving a control signal from the system manager. The method according to claim 1,
Each of the plurality of photovoltaic modules further comprises a monitoring module for generating monitoring information of the solar cell module and monitoring information of the small capacity inverter. The method according to claim 1,
The system manager, the photovoltaic power generation system further comprises a control signal module for generating a control signal for operating and stopping the small-capacity inverter in each photovoltaic module to transmit to the communication module. The method according to claim 1,
The system manager is configured to process monitoring information of the solar cell module and monitoring information of the small capacity inverter received from each solar power module, and in real time, an operating state of each solar power module and a state of a commercial power system. And a total solar power generation system. The method according to claim 1,
Further includes at least one router,
The at least one router receives the monitoring information of the solar cell module and the monitoring information of the small-capacity inverter from the communication module and transmits the monitoring information to the system manager, and receives a control signal from the system management and transmits the control signal to the communication module for communication. Solar power system, characterized by extending the distance. In claim 1,
The system manager includes a coordinator, and the coordinator finally receives the monitoring information transmitted through the router, transmits the monitoring information to the system management unit, and also enables the real-time monitoring from the outside through the Internet. ,. The method according to claim 1,
The small-capacity inverter is characterized in that each of the plurality of solar cell modules can be connected to the solar power generation system. The method according to claim 1,
AC power is connected to each of the small capacity inverters in the plurality of photovoltaic modules to collect AC power.
Photovoltaic power generation system, characterized in that for transmitting the collected AC power to the commercial power system. The method according to claim 1,
Each of the plurality of small-capacity inverters in the plurality of photovoltaic modules separately transmits AC power to a commercial power system.

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