KR101794975B1 - Photovoltaic power generation system with safety cut-off function - Google Patents

Abstract

The present invention relates to a photovoltaic power generation system having a safety cut-off function. More specifically, the present invention relates to a photovoltaic power generation system having a safety cut-off function which detects an occurrence of a ground fault in a photovoltaic power generation, and has a safety cut-off function automatically cutting off overcurrent through a cut-off circuit when detecting the ground fault for preventing fire due to overheat in a connection board according to a ground fault generation. The photovoltaic power generation system having a safety cut-off function distinguishes the ground fault generation due to the occurrence of abnormality of a solar module or a line from a negative ground fault and a positive ground fault, precisely detects the occurrence of the ground fault corresponding to each polarity, blocks the overcurrent according to the ground fault generation, efficiently protects a component composing a photovoltaic generation system, and prevents fire.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a photovoltaic power generation system and a safety cut-

The present invention relates to a photovoltaic power generation system having a safety shutoff function, and more particularly, to a photovoltaic power generation system having a safety shutoff function, and more particularly, And more particularly, to a solar power generation system having a safety shutoff function for automatically shutting off an overcurrent through a circuit.

Currently, various modules for converting renewable energy to electric energy form are being developed. Among them, a solar module for converting sunlight into electric energy and a photovoltaic power generation system using the same are attracting much attention.

The photovoltaic power generation system that constructs the solar modules in the form of an array and obtains the generation power based on the sunlight has been spreading more and more easily because the system configuration is easier than other types of renewable energy.

However, since such a photovoltaic power generation system is disposed and operated outdoors, it is directly exposed to a change in the external environment. As a result, damage to the photovoltaic module constituting the photovoltaic power generation system or a plurality of photovoltaic arrays Such as line damage between the connection module and the photovoltaic module, which collects the generated power from the inverter and provides it to the inverter.

As a representative example of such a problem, insulation is deteriorated due to various factors such as deterioration due to external exposure of a solar module and a line abnormality between a solar module and a connection board, so that a ground fault occurs. High voltage over the reference is generated in the line or connection panel, and the circuit is damaged by the overcurrent or it causes fire in severe case.

Therefore, in order to prevent the danger due to such a ground fault, a conventional photovoltaic power generation system constitutes a circuit breaker inside the connection panel or as a separate device.

At this time, the conventional circuit breaker defines the rated output for the plurality of solar modules, and operates to cut off the generated power provided from the solar module when the overcurrent exceeds the rated capacity according to the rated output.

However, it is rare that the rated output is output from the solar cell module whose output varies irregularly according to the external environment change. Therefore, even when the ground fault occurs, the circuit breaker does not reach the overcurrent exceeding the rated capacity, The generated power is transmitted to the inverter, and thus there is a problem that the circuit breakage or fire can not be prevented.

Korean Patent No. 10-0930132

The present invention relates to a photovoltaic power generation system and a photovoltaic power generation system, and more particularly, to a photovoltaic power generation system and a photovoltaic power generation system, which are capable of accurately detecting occurrence of a ground fault caused by an abnormality of a photovoltaic module or a line, To effectively protect and prevent fire.

In addition, the present invention divides a power generation output terminal of a solar module into a positive terminal and a negative terminal, and distinguishes whether a ground fault occurs on a line connected to each terminal by a positive lock and a negative lock, It is intended to support the manager to make it easy to judge and to support the maintenance of the line or equipment corresponding to the polarity.

In addition, it is an object of the present invention to ensure the insulation between the circuits constituting the inside of the connection board and to detect whether a ground fault has occurred correctly, thereby improving the accuracy and reliability of ground fault detection.

A plurality of solar modules according to an embodiment of the present invention, a connection module for connecting voltages of the solar modules, and an inverter for converting generated power applied through the connection module to a commercial power source, The photovoltaic power generation system includes a voltage divider circuit connected between power generation output terminals of the photovoltaic module, and a comparator for comparing the voltage provided through the voltage divider circuit with a reference voltage, A second ground fault detecting unit for comparing a voltage provided through the voltage dividing circuit with a reference voltage and providing a second measurement signal when a positive lock is detected in accordance with a positive voltage value exceeding a preset reference value; A ground fault detection unit for detecting ground faults according to at least one of the first and second measurement signals received through the first and second ground fault detection units, May comprise the IGBT is operated on the basis of the control signal of the control unit and the control unit outputting a control signal to a variable reference block which selectively blocks the current supplied from the power supply output terminal of the solar module parts.

The first ground fault detecting unit may include a first resistive element part having a plurality of resistance elements whose one side is connected in series to the voltage dividing circuit so as to lower the positive voltage of the voltage dividing circuit, And a second resistance element part connected to the other side of the first and second resistance element parts and connected to the first resistance element part and the second resistance element part in accordance with a difference between an input voltage through the first resistance element part and an input voltage through the second resistance element part, And a first differential amplifier for outputting a first measurement signal.

According to an embodiment of the present invention, the control unit may include a first light emitting diode which emits light according to the first measurement signal outputted through the first differential amplifier, and a second light emitting diode which is switched according to light emission of the first light emitting diode, And a first phototransistor for providing the first output signal corresponding to the first output signal to the control unit.

In one embodiment of the present invention, the first and second resistive elements are symmetrically formed on the PCB, and a groove for insulation is formed on the PCB between the first and second resistive elements. .

The second ground fault detection unit may include a third resistive element part having a plurality of resistance elements whose one side is connected in series to the voltage dividing circuit so as to lower the negative voltage of the voltage dividing circuit, And a fourth resistor element connected to the other end of the third resistor element and the fourth resistor element, the second resistor element being connected to the first resistor element and the second resistor element, And a second differential amplifier that outputs a measurement signal.

In one embodiment of the present invention, the control unit may include a second light emitting diode that emits light according to the second measurement signal output through the second differential amplifier, and a second light emitting diode that is switched according to light emission of the second light emitting diode, And a phototransistor for providing a second output signal corresponding to the second output signal.

According to an embodiment of the present invention, the third and fourth resistor elements are symmetrically formed on the PCB, and grooves for insulation are formed on the PCB between the third resistor element and the fourth resistor element. have.

In one embodiment of the present invention, the control unit includes an output unit including a photocoupler connected to the IGBT of the blocking unit, and provides the control signal to the blocking unit through the photocoupler.

In one embodiment of the present invention, the IGBT includes a collector terminal connected to an output of the photocoupler and a gate terminal, the collector terminal being connected to one of the power generation output terminals of the photovoltaic module, and an emitter terminal And a diode connected at one end to a collector terminal of the transistor and at the other end to the emitter terminal, the transistor being switched from the output to the gate terminal according to a variable output voltage received, And selectively connecting the output of the optical module and the inverter.

According to the present invention, it is possible to accurately detect the occurrence of a ground fault corresponding to each polarity by dividing the occurrence of a ground fault due to an abnormality of a solar module or a line into a sunroof and a sunroof, Thereby effectively protecting components constituting the solar power generation system and preventing fire.

In addition, the present invention divides and displays the polarity corresponding to the occurrence of a ground fault when the ground fault occurs, so that the administrator can easily identify the polarity where the ground fault occurs, and also confirms the output terminal, So that it can be easily repaired.

In addition, according to the present invention, it is possible to ensure the insulation between the circuits constituting the inside of the connection board to detect whether or not a ground fault has occurred correctly, and to protect the connection circuit from a high voltage generated by the generated power supplied from the solar module, So that accuracy and reliability of ground fault detection can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram of a solar power generation system having a safety shutdown function according to an embodiment of the present invention; FIG.
BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a photovoltaic power generation system,
FIG. 3 is a circuit diagram for detecting a false alarm in a solar power generation system having a safety shut-off function according to an embodiment of the present invention. FIG.
FIG. 4 is a circuit diagram for detecting sound closure in a solar power generation system having a safety shut-off function according to an embodiment of the present invention. FIG.
5 is an exemplary view illustrating an insulation structure between resistance elements for voltage drop in a solar power generation system having a safety shutdown function according to an embodiment of the present invention.
FIG. 6 is a circuit diagram of a control unit and a blocking unit for blocking a circuit according to ground fault detection in a solar power generation system having a safety shutoff function according to an embodiment of the present invention. FIG.

Hereinafter, detailed embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a photovoltaic power generation system having a safety shutdown function according to an embodiment of the present invention. As shown in FIG. 1, the photovoltaic power generation system includes a plurality of solar modules 10, And an inverter 200 for converting generated power applied through the connection unit 100 to a commercial power source.

At this time, the plurality of solar modules 10 may be configured as a solar array 1 configured in the form of an array connected in series, and the connection module 100 may be connected to a plurality of solar arrays 1 So that the voltage can be connected.

In addition, the connection board 100 prevents circuit damage due to overcurrent when the photovoltaic module 10 is damaged or when a ground fault occurs due to a short circuit due to a line abnormality between the solar cell module 10 and the connection board 100 It is possible to accurately detect the ground fault and to prevent the over current.

2, the connection block 100 includes a voltage divider circuit 110, a first ground fault detection unit 20, a second ground fault detection unit 30, a control unit 120, and a shutoff unit 130 .

First, the voltage dividing circuit 110 is connected to the power generation output terminal (hereinafter, referred to as " output terminal ") of the photovoltaic module 10 constituting the terminating end of the solar array 1 constituted by the plurality of solar modules 10, . ≪ / RTI >

The voltage dividing circuit 110 includes a first resistor R1 having one end connected to a negative terminal (negative terminal or negative voltage output terminal) of the generated power output terminals, and a first resistor R1 having one end connected to the positive terminal (R1, R2) connected to one end of the first resistor element (R1, R2) and the other end connected to the ground, and a second resistor element And a resistance element R3.

In the above-described configuration, when at least one of the plurality of photovoltaic modules is damaged, or when a ground fault occurs due to a line abnormality or an insulation resistance between the photovoltaic module and the connection panel, At least one of the positive voltage and the negative voltage is grounded and flows to the ground.

Accordingly, in the case where the voltage V1 applied to the third resistance element R3 is 0 V in a state where there is no ground fault, and the ground fault occurs in the negative voltage line connected to the negative terminal of the solar module 10, V1 Voltage is applied to the positive terminal of the solar module 10 and a ground fault occurs in the positive voltage line connected to the positive terminal of the solar module 10, a negative voltage is applied to the voltage V1.

The control unit 120 is connected to the first and second ground fault detection units 20 and 30 for detecting ground fault based on the voltage applied from the voltage dividing circuit 110 to the voltage V1, And at least one of the positive lock and the negative lock is controlled to control the blocking unit 130 to prevent the solar array 1 or a plurality of The power supplied from the solar module 10 to the inverter 200 can be cut off, and the description thereof will be described in more detail with reference to the drawings based on the above-mentioned contents.

2, the first and second ground fault detectors 20 and 30 may be connected to the voltage divider circuit 110, and the first ground fault detector 20 may be connected to the voltage divider circuit 110, The second ground fault detection unit 30 detects whether a ground fault is caused by the negative voltage of the voltage divider circuit 110 or not.

At this time, the first and second ground fault detection units 20 and 30 may be included in the controller 120 as an analog input unit 121.

Referring to FIG. 3, the detailed operation of the first ground fault detection unit 20 and the control unit 120 will be described. As shown in the drawing, the first ground fault detection unit 20 includes the voltage divider circuit 110, A first resistor element 21 formed of a plurality of resistors R11, R12, and R13 connected in series to the voltage dividing circuit 110 so as to reduce the negative voltage of the negative voltage, A second resistor element 22 formed of a plurality of resistor elements R21, R22 and R23 connected to the ground and a second resistor element 22 connected to the other end (the other end) of the first and second resistor elements 21 and 22, And a first differential amplifier 23 for outputting a result signal of a difference between an input voltage through the first resistance element part 21 and an input voltage through the second resistance element part 22.

At this time, one side is connected to the other side of the first resistance element part 21 for voltage drop of the voltage V1 inputted to the first differential amplifier 23 through the first resistance element part 21, A resistance element R14 connected to one end of the second resistor element 22 and a resistor element R24 connected to the other end of the second resistor element 22 is connected to the ground, .

In the above-described configuration, when positive voltage of the solar module 10 is grounded and positive lock is generated, a negative voltage is applied to V1 of the voltage divider circuit 110, and the negative voltage is applied to the first resistor element 21 And is applied to the input voltage of the first differential amplifier 23.

At this time, since the voltage provided from the photovoltaic module 10 is provided at a high voltage of several hundreds or a thousand volts, circuit damage may occur when the high voltage is applied to the first differential amplifier 23 through the voltage divider circuit 110 .

In order to prevent this, a first resistance element section 21 composed of a plurality of resistance elements R11, R12, and R13 drops the voltage applied from the voltage divider circuit 110 in accordance with the generation of the positive lock voltage, (23).

The first resistive element 21 includes a plurality of resistive elements R11, R12, and R13 to prevent an arc due to a high voltage, and a plurality of resistive elements R11, R12, R13) may be connected in series so as to be spaced apart from a predetermined reference distance.

The second resistance element 22 is connected to the ground to provide a ground reference voltage to the first differential amplifier 23 and includes a plurality of resistance elements R21, R22, and R23, The resistors R21, R22, and R23 may be configured to be mutually symmetric with the resistive elements R11, R12, and R13 of the first resistive element portion 21. [

At this time, each of the first and second resistance element portions 22 is preferably composed of three resistance elements.

According to the above-described configuration, when the OV voltage is applied from the voltage divider circuit 110 in the steady state in which the ground fault does not occur, and the positive lock is generated, the first differential amplifier 23 generates a voltage change from the voltage divider circuit 110 And a negative voltage is applied to the input voltage through the first resistor element 21.

Accordingly, the first differential amplifier 23 generates a voltage difference (voltage difference) between the negative voltage input through the first resistance element section 21 and the reference voltage input through the second resistance element section 22 And generates a first measurement signal when the voltage difference is equal to or greater than a preset reference value, and provides the first measurement signal to the controller 120. [

When receiving the first measurement signal from the first ground fault detection unit 20, the control unit 120 generates a control signal so that the generated power of the solar module 10 is not provided to the inverter 200 The control signal may be provided to the blocking unit 130 that cuts off the connection between the photovoltaic module 10 and the inverter 200.

The controller 120 may include a first light emitting diode D2 emitting light according to the first measurement signal output through the first differential amplifier 23 and a second light emitting diode D2 emitting light according to the light emission of the first light emitting diode D2, And a first phototransistor (TR1) including a first phototransistor (TR1) for providing a first output signal corresponding to a first measurement signal provided from the first differential amplifier (23) to the controller (130) 1 ground fault detection unit 20. [

Accordingly, the controller 120 receives the first measurement signal while being electrically insulated from the first ground fault detector 20, thereby preventing the high voltage from being applied to the controller 120 from the first ground fault detector 20 So that the controller 120 can be prevented from being damaged.

In this case, the first photocoupler unit may be included in the controller 120, and the controller 120 may include a controller configured to include the microprocessor and generate the control signal.

Thereby, the controller can receive the first output signal received through the first photocoupler as the first measurement signal and generate the control signal in response to the first measurement signal upon receiving the first output signal have.

The first light emitting diode D2 has one side connected to the power source and the other side connected to the output terminal of the first differential amplifier 23, When a first measurement signal is supplied from the first light emitting diode 23, a power voltage is applied to the first light emitting diode D2 to emit light.

Accordingly, the first phototransistor TR1 is connected to the power source and the other is connected to the ground, and is switched according to the light emission of the first light emitting diode D2. have.

The first phototransistor TR1 has a collector terminal connected to the power source, an emitter terminal connected to the ground, and a collector terminal of the first phototransistor TR1, The resistor element R4 may be connected between the resistor R5 and the resistor R5.

The controller 120 is connected between the output terminal of the first differential amplifier 23 and the first light emitting diode D2 and outputs a first measurement signal through the output terminal of the first differential amplifier 23 And a light-emitting diode (LED) D1 configured to emit light by applying an operation voltage according to the power supply voltage through the first light-emitting diode D2. The positive-polarity lock display unit may include a first differential amplifier 23 to emit light according to the first measurement signal to indicate that a positive lock has occurred.

At this time, as shown in the figure, a plurality of diodes and a plurality of resistors connected to the power source and the ground are connected between the first differential amplifier 23 and the first light emitting diode D2, The power source voltage may be applied to the first light emitting diode D2 to allow the current to flow through the first light emitting diode D2.

Referring to FIG. 4, the detailed operation of the second ground fault detecting unit 30 and the control unit 120 will be described. As shown in FIG. 4, the second ground fault detecting unit 30 includes: A third resistance element part 31 composed of a plurality of resistance elements R31, R32 and R33, one side of which is connected in series to the voltage-dividing circuit 110, for lowering the positive voltage of the positive voltage source 110, A fourth resistance element part 32 composed of a plurality of resistive elements R41, R42 and R43 and connected to the other side of the third and fourth resistance element parts 31 and 32, And a second differential amplifier 33 for detecting the occurrence of a sound closure in response to a difference between an input voltage through the first resistive element 31 and an input voltage through the fourth resistive element 32 and outputting a second measurement signal.

At this time, one terminal is connected to the other terminal of the third resistor element 31 for voltage drop of the voltage V1 inputted to the third differential amplifier 33 through the third resistor element 31, And a resistor R44 having one end connected to the other end of the fourth resistance element part 32 and the other end connected to ground is connected to the ground fault detection part 30 .

In the above-described configuration, when a negative voltage of the solar module 10 is grounded and a shadow lock is generated, a positive voltage is applied to V1 of the voltage divider circuit 110, and the positive voltage is applied to the third resistor element 31 And is applied to the input voltage of the second differential amplifier 33.

At this time, the high voltage provided from the photovoltaic module 10 may be applied to the second differential amplifier 33 through the voltage divider circuit 110 to cause circuit damage, as described above. To prevent this, The third resistor element 31 composed of the resistive elements R31, R32 and R33 can drop the high voltage applied from the voltage divider circuit 110 according to the generation of the sound closure to provide the voltage to the second differential amplifier 33 have.

The third resistive element 31 includes a plurality of resistive elements R31, R32, and R33 for preventing an arc due to a high voltage and a plurality of resistive elements R31, R32, and R33 for preventing corona, Can be connected in series so as to be spaced apart from a predetermined reference distance.

The fourth resistance element part 32 is connected to the ground to provide a ground reference voltage to the second differential amplifier 33 and a plurality of resistance elements of the same number as the third resistance element part 31 R42, and R43 of the third resistance element section 31 may be configured to be mutually symmetrical with respect to the resistance elements R31, R32, and R33 of the third resistance element section 31, have.

At this time, each of the third and fourth resistance element portions 32 is preferably composed of three resistance elements.

According to the above-described configuration, when the OV voltage is applied from the voltage divider circuit 110 in a steady state in which no ground fault occurs, the second differential amplifier 33 generates a voltage change when the shadows are generated, And a positive voltage is applied to the input voltage through the third resistance element portion 31. [

Accordingly, the second differential amplifier 33 generates a voltage difference (voltage difference) between the positive voltage inputted through the third resistance element part 31 and the reference voltage inputted through the fourth resistance element part 32 And generates a second measurement signal when the voltage difference is equal to or greater than a preset reference value, and provides the second measurement signal to the controller 120. [

When receiving the second measurement signal from the second ground fault detection unit 30, the control unit 120 generates a control signal so that the generated power of the solar module 10 is not provided to the inverter 200 The control signal may be provided to the blocking unit 130 that cuts off the connection between the photovoltaic module 10 and the inverter 200.

The controller 120 may include a second light emitting diode D4 that emits light according to the second measurement signal output through the second differential amplifier 33 and a second light emitting diode D4 that emits light according to the light emission of the second light emitting diode D4. And a second phototransistor unit including a second phototransistor TR2 for providing a second output signal corresponding to the second measurement signal to the control unit 130. The second photocoupler unit may be connected to the second ground fault detection unit 30 .

The control unit 120 receives the second measurement signal while being electrically insulated from the second ground fault detection unit 30 and prevents the second ground fault detection unit 30 from applying a high voltage to the control unit 120 So that the controller 120 can be prevented from being damaged.

Here, the second photocoupler unit may be included in the controller 120, and the controller included in the controller may receive the second output signal as the second measurement signal through the second photocoupler unit And generate the control signal in response to the second measurement signal upon receiving the second output signal.

More specifically, the second light-emitting diode D4 has one side connected to the output terminal of the second differential amplifier 33, the other side connected to the ground, and the second differential When the second measurement signal is supplied from the amplifier 33, a voltage is applied to the second light emitting diode D4 to emit light.

Accordingly, the second phototransistor TR2 is connected to the power source and the other is connected to the ground, and is switched according to the light emission of the second light emitting diode D4. can do.

At this time, the second phototransistor TR2 has a collector terminal connected to the power source, an emitter terminal connected to the ground, and a resistor element R5 between the collector terminal of the second phototransistor TR2 and the power source Can be connected.

The control unit 120 is connected between the output terminal of the second differential amplifier 33 and the second light emitting diode D4 and outputs a second measurement signal through the output terminal of the second differential amplifier 33 And a light emitting diode (D3) that emits light when an operation voltage according to the second measurement signal is applied. The corresponding sound field lock display unit may be connected to the second measurement signal of the second differential amplifier It is possible to indicate that a loudspeaker has occurred due to light emission.

As shown in the figure, a plurality of diodes and a plurality of resistors connected to the power source and the ground are connected between the second differential amplifier 33 and the second light emitting diode D4, The power source voltage may be applied to the second light emitting diode D4 so that current flows through the first light emitting diode D4.

Through the above-described configuration, if a positive lock or a negative lock is generated, the control unit 120 displays whether a ground fault has occurred or not through the positive lock display unit or the negative lock display unit, and at the same time, The light emitting diode can be displayed by emitting light.

Accordingly, it is possible to easily identify the polarity in which the ground fault occurs, and at the same time, to confirm the output terminal or the line of the solar module related to the polarity, And to provide repair services.

In the above-described configuration, the voltage divider circuit 110, the first and second ground fault detection units 20 and 30, the control unit 120, and the cutoff unit 130 constituting the connection board 100 are made of PCB Circuit Board).

In this case, when moisture is generated in the PCB, a short circuit may occur between the first resistive element part 21 and the second resistive element part 22 of the first ground fault detection part 20. The second ground fault detection part 30 ) May also cause a short circuit between the third resistance element part 31 and the fourth resistance element part 32. [

Such a short circuit may cause circuit damage of the connection board 100 or, in severe cases, may lead to fire.

5, the first and second resistance element portions 21 and 22 connected to the connector terminal of the first ground fault detection portion 20 connected to the voltage divider circuit 110 And a groove (A) for insulation between the first and second resistance element portions (21, 22) is formed between the first and second resistance element portions (21, 22) So that the current flowing through the first resistive element 21 can be prevented from flowing into the second resistive element 22.

Likewise, the third and fourth resistive element portions 31 and 32 are symmetrically formed on the PCB, and the third and fourth resistive element portions 31 and 32 are connected to the connector terminal of the second ground fault detection portion 30 connected to the voltage divider circuit 110, A groove for insulation between the third and fourth resistive elements 31 and 32 is formed on the PCB between the fourth resistive elements 31 and 32 and flows through the third resistive element 31 So that current can be prevented from flowing into the fourth resistance element portion 32.

2, the shutoff unit 130 receives a control signal from the control unit 120 to selectively cut off the connection between the output of the solar module and the inverter, thereby preventing an overcurrent from being generated due to a ground fault At the same time, the fire can be prevented.

The blocking unit 130 may receive the generated power of the photovoltaic module 10 and provide the generated power to the inverter 200. Between the blocking unit 130 and the photovoltaic module 10, a fuse unit 11 and a diode 12 for blocking a reverse current may be configured.

The blocking unit 130 includes an IGBT (Insulated Gate Bipolar Mode Transistor) 131 and operates the IGBT 131 based on a control signal of the controller 120 on a variable basis, The current provided from the power generation output terminal of the optical module 10 can be selectively cut off.

When a high voltage is applied through the IGBT 131 of the blocking unit 130 and the control unit 120 transmits a control signal to the blocking unit 130 through the line, 120 and may cause circuit damage of the control unit 120.

6, the control unit 120 includes an output unit 122 including a third photocoupler unit 300 connected to the IGBT 131 of the blocking unit 130 And may provide the control signal to the blocking unit 130 through the output unit 122 including the third photocoupler unit 300.

In this case, the output unit 122 may be a driver that transmits signals while maintaining electrical insulation with the blocking unit 130.

Accordingly, the control unit 120 can provide the control signal to the blocking unit 130 while maintaining electrical insulation from the blocking unit 130 through the third photocoupler unit 300, The control unit 120 can be safely protected from the voltage applied to the blocking unit 130.

The IGBT 131 has a collector terminal connected to one of the power generation output terminals of the photovoltaic module 10 and a gate terminal connected to the output of the blocking unit 130, And an emitter terminal connected to the inverter 200. The transistor TR3 has one end connected to a collector terminal of the transistor TR3 and the other end connected to the emitter terminal to prevent reverse current And a diode D5 which is connected to the power source.

The transistor TR3 formed in the IGBT 131 is switched according to the variable output voltage supplied from the output section 122 to the gate terminal of the transistor TR3 to output the output of the photovoltaic module 10 And the inverter 200 can be selectively connected.

For example, the output unit 122 provides either the + 15V or the -10V to the gate of the transistor TR3 of the IGBT 131 according to the control signal, The IGBT 131 of the IGBT 131 may selectively block the current supplied from the photovoltaic module 10 from being transmitted to the inverter 200 according to an input voltage provided from the output unit 122.

At this time, a resistor R6 connected between the output part 122 and the gate terminal of the IGBT 131 may be formed in the connection part 100 or the blocking part 130.

According to the present invention, it is possible to accurately detect the occurrence of a ground fault due to an abnormality of a solar module or a line, to enable rapid measures to be taken, and to precisely block the overcurrent supplied from the solar module The components constituting the power generation system can be effectively protected and fire can be prevented.

Also, according to the present invention, it is possible to accurately detect the occurrence of a ground fault corresponding to each polarity by dividing a ground fault caused by an abnormality of a photovoltaic module or a line into a sunk rock and a sunny rock. It is possible to effectively protect the components constituting the solar power generation system.

In addition, according to the present invention, it is possible to ensure the insulation between the circuits constituting the inside of the connection board to detect whether or not a ground fault has occurred correctly, and to protect the connection circuit from a high voltage generated by the generated power supplied from the solar module, It is possible to improve the accuracy and reliability of the ground fault detection.

Meanwhile, in the above-described configuration, the connection unit 100 may further include a temperature sensor unit, a fan unit, and a driving unit for driving the fan unit.

The control unit 120 may drive the fan unit through the driving unit to lower the temperature inside the connection unit when a temperature equal to or higher than a preset reference value is detected based on a sensing signal provided from the temperature sensor unit, It is possible to prevent the occurrence of fire in the connection unit in advance.

In addition, in the above-described configuration, the control unit 120 includes a communication unit for communication with an external device, generates detection information upon detection of a ground fault according to any one of the first and second measurement signals, Lt; / RTI >

In addition, the controller 120 may determine the blocking state of the blocking unit according to whether the ground fault is detected, and may generate state information on the blocking unit and transmit the state information to the external apparatus through the communication unit.

In addition, the control unit 120 may transmit the sensing signal received from the temperature sensor unit to the external device, and may also transmit status information on the status of the driving unit that drives the fan unit to the external device.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or essential characteristics thereof. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

1: solar array 10: solar module
20: first ground fault detection unit 30: second ground fault detection unit
100: connection board 110: voltage-dividing circuit
120: control unit 130:
200: Inverter

Claims (9)

1. A photovoltaic power generation system comprising a plurality of photovoltaic modules, a connection panel for connecting voltages of the photovoltaic modules, and an inverter for converting generated power applied through the connection panel to a commercial power supply,
A voltage divider circuit connected between power generation output terminals of the solar module;
A first ground fault detecting unit for comparing a voltage provided through the voltage divider circuit with a reference voltage to provide a first measurement signal when a sound closure occurs due to positive voltage detection over a preset reference value;
A second ground fault detector for comparing a voltage provided through the voltage divider circuit with a reference voltage to provide a second measurement signal when a positive lock is detected according to a negative voltage detection that is greater than a preset reference value;
A control unit for outputting a control signal when a ground fault is detected according to at least one of first and second measurement signals received through the first and second ground fault detection units; And
And a blocking unit for selectively blocking the current provided from the power generation output terminal of the photovoltaic module by operating the IGBT based on a control signal of the control unit,
The first ground fault detection unit
A first resistive element having a plurality of resistive elements connected in series to the voltage-dividing circuit, one side of which is connected to the voltage-dividing circuit in order to drop the positive voltage of the voltage-dividing circuit;
A second resistive element comprising a plurality of resistive elements having one side connected to ground; And
And a first differential amplifier connected to the other side of the first and second resistance elements and outputting the first measurement signal according to a difference between an input voltage through the first resistance element and an input voltage through the second resistance element In addition,
A plurality of resistive elements formed in the first resistive element portion and a plurality of resistive elements formed in the second resistive element portion,
A plurality of resistors connected in series so as to be spaced apart from a predetermined reference distance between the plurality of resistive elements so as to prevent corona,
Wherein the first and second resistive elements are symmetrically formed on the PCB and a groove for insulation between the first and second resistive elements is formed on the PCB. .
delete The method according to claim 1,
The control unit may include a first light emitting diode that emits light according to the first measurement signal output through the first differential amplifier, a first output signal that is switched according to the light emission of the first light emitting diode and corresponds to the first measurement signal, A first phototransistor for providing the control signal to the control unit, and a tone lock display unit connected between the output terminal of the first differential amplifier and the first light emitting diode for indicating that a sound shadow is generated when the first measurement signal is output Wherein the solar cell system has a safety shut-off function.
delete The method according to claim 1,
The second ground fault detection unit
A third resistive element having a plurality of resistive elements connected in series to the voltage dividing circuit, one side of which is connected in series to the negative voltage of the voltage divider circuit;
A fourth resistive element comprising a plurality of resistive elements connected at one end to ground; And
And a second differential amplifier connected to the other side of the third and fourth resistance elements for outputting a second measurement signal according to a difference between an input voltage through the third resistance element and an input voltage through the fourth resistance element,
A plurality of resistive elements formed in the third resistive element part and a plurality of resistive elements formed in the fourth resistive element part,
Wherein the plurality of resistors are connected in series so as to be spaced apart from a predetermined reference distance between the plurality of resistive elements so as to prevent corona, in order to prevent arcing due to high voltage.
6. The method of claim 5,
The control unit may include a second light emitting diode that emits light according to the second measurement signal output through the second differential amplifier, a second output signal that is switched according to the light emission of the second light emitting diode and corresponds to the second measurement signal And a positive lock display unit connected between the output terminal of the second differential amplifier and the second light emitting diode for indicating that a positive lock is generated when the second measurement signal is outputted, Wherein the solar cell system has a safety shut-off function.
6. The method of claim 5,
Wherein the third and fourth resistive elements are symmetrically formed on the PCB and grooves for insulation are formed on the PCB between the third and fourth resistive elements. .
The method according to claim 1,
Wherein the control unit includes an output unit including a photocoupler connected to the IGBT of the blocking unit, and provides the control signal to the blocking unit through the photocoupler.
9. The method of claim 8,
The IGBT
A collector terminal connected to an output of the photocoupler and a gate terminal, the collector terminal being connected to one of the power generation output terminals of the photovoltaic module, and the emitter terminal connected to the inverter; And
And a diode connected at one end to the collector terminal of the transistor and at the other end to the emitter terminal,
Wherein the transistor is switched according to a variable output voltage provided from the output unit to the gate terminal to selectively connect the inverter with the output of the solar module.

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