KR101743908B1 - A bypass circuit system for defective photovoltaic modules of the solar power array - Google Patents

Abstract

The present invention relates to a PV failure and a faulty module bypass system of a solar power generation apparatus, in which failure and malfunctioning modules are detected for a PV module installed in a photovoltaic power generation, so that normal efficiency and operation of the solar power generation are maintained. 1. A photovoltaic device comprising a plurality of PV modules connected in series; A bypass module installed in each of the PV modules and configured to bypass the PV modules; A temperature sensor installed in each of the PV modules for measuring a power of the corresponding PV module, a temperature sensor for measuring a temperature of the PV module, and a TEV detecting unit for detecting a transient ground voltage (TEV) A sensor module comprising a sensor; And a controller for receiving a detection value from the sensor module, calculating a power of the corresponding PV module based on the detected value of the power, determining a probability distribution of the detected power, temperature, and transient ground voltage, And transmits a command to the bypass module to bypass the bypass module if the detected value of the ground voltage falls within a predetermined range in the probability distribution, And bypassing if the detected value of the temperature and transient ground voltage is not less than a predetermined range.
By monitoring the photovoltaic modules (PV modules) and detecting and bypassing the faulty and faulty modules, the PV system can be managed through monitoring and replacement of faults and faulty modules in real time.

Description

[0001] The present invention relates to a photovoltaic (PV)

The present invention relates to a photovoltaic power generation apparatus and a photovoltaic power generation system, which detect and fail a PV module of a photovoltaic power generation apparatus for photovoltaic power generation, PV failure and poor module bypass system.

In addition, the present invention detects the output power, the heat generation temperature, and the transient earth voltage (TEV) caused by the arc discharge of each PV module, and the deviation of each module by these detected values is compared with the deviation of other modules To a PV failure and a bad module bypass system of a photovoltaic power generation apparatus which judges a difference to judge a failure and a failure module.

Increased interest in and investment in renewable energy has led to the rapid development of the solar energy industry. In the last decades, the demand for renewable energy has increased significantly due to the disadvantages of fossil fuels and the greenhouse effect. Among various types of renewable energy sources, solar energy has become the most promising and attractive due to advances in power electronics technology. Photovoltaic (PV) power supplies are used in many applications today due to the advantages of no maintenance and no pollution.

Photovoltaic power generation system is a power generation facility that operates in a natural environment over a long period of time for 20 years or more, so it is necessary to maintain long-term reliability and avoid accident risk. In particular, if an abnormal condition occurs, if the measures are not taken immediately, there is a need to develop a technology capable of reducing the loss because the generation amount and the economic loss may occur.

However, due to the high initial cost and limited life span of the PV module, continuous management is required. However, it is practically impossible to manage each module in real time with limited human resources. Therefore, it is necessary to monitor each module in real time and to manage by monitoring and replacing faulty and defective modules.

In order to solve the above problems, a photovoltaic power generation system capable of bypassing a faulty and defective module has been developed (Patent Documents 1 and 2). The above prior art detects roughness or voltage in the solar cell module, and if they are smaller than the reference value, it determines that the module is a failure or a bad module and bypasses it.

In addition, the temperature inside the module may increase due to generated power in each solar cell module, or an arc discharge may occur. In addition, the insulation in the PV module may be destroyed due to deterioration or corrosion due to high temperature or arc discharge. Therefore, if a certain PV module is abnormally high temperature or discharge, the corresponding solar cell module should also be excluded from the solar power generation device. Accordingly, when the temperature of the PV module or the discharge voltage exceeds the predetermined reference value, these PV modules are judged to be faulty and defective modules and bypassed.

However, solar power varies greatly depending on the amount of sunshine. In particular, the amount of sunlight fluctuates rapidly depending on the atmospheric conditions such as seasons, time zones, and clouds. If the reference value is fixedly set in a situation where the amount of sunshine fluctuates as described above, there is a problem that the solar cell module is detected as being too much or too little.

In addition, if the reference temperature is set to a fixed value in advance for the heat generation temperature and the discharge voltage of the PV module, the overall heat generation temperature or discharge voltage may be changed depending on the atmospheric environment such as the amount of sunshine or drying of the air. Therefore, if the reference value is fixed, a problem that too much or too little solar cell module can be detected as failure and defect also occurs.

Korean Registered Patent No. 10-1279554 (Registered on June 21, 2013) Japanese Patent Application Laid-Open No. 2000-174308 (published on June 23, 2000)

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and it is an object of the present invention to provide a PV module which detects output power, heat generation temperature and transient ground voltage (TEV) caused by arc discharge of each PV module, And a PV failure and a defective module bypass system of a photovoltaic power generation apparatus which judges a relative difference with respect to a deviation of another module and judges that the module is a failure and a failure module.

Further, the object of the present invention is to provide a PV module that receives the detected values of power, heat temperature, and transient ground voltage due to electric discharge in each PV module to obtain a probability distribution of detected values, PV module of the PV system and a faulty module bypass system that controls the corresponding PV module to be bypassed.

In order to achieve the above object, the present invention relates to a PV failure and a faulty module bypass system of a photovoltaic power generation apparatus, comprising: a photovoltaic power generation apparatus comprising a plurality of PV modules connected in series; A bypass module installed in each of the PV modules and configured to bypass the PV modules; A temperature sensor installed in each of the PV modules for measuring a power of the corresponding PV module, a temperature sensor for measuring a temperature of the PV module, and a TEV detecting unit for detecting a transient ground voltage (TEV) A sensor module comprising a sensor; And a controller for receiving a detection value from the sensor module, calculating a power of the corresponding PV module based on the detected value of the power, determining a probability distribution of the detected power, temperature, and transient ground voltage, And transmits a command to the bypass module to bypass the bypass module if the detected value of the ground voltage falls within a predetermined range in the probability distribution, And bypassing if the detected value of the temperature and transient ground voltage is not less than a predetermined range.

The present invention also relates to a PV failure and faulty module bypass system of a photovoltaic power generation apparatus, wherein the bypass module includes a bypass circuit that directly connects or bypasses an output of the installed PV module with an adjacent PV module, And a relay for switching the bypass circuit. The direct connection or the bypass connection of the PV module is controlled by receiving an instruction from the main control unit and controlling the relay of the bypass circuit.

In addition, the present invention relates to a PV failure and a bad module bypass system of a solar power generation apparatus, wherein the control apparatus includes a microprocessor, and the power, temperature, and temperature of each PV module transmitted by the RS- And a program for receiving the TEV voltage and judging whether each PV module is faulty or defective. The microprocessor performs the faulty and bad module determination program to perform the faulty and defective module detection and bypass operation .

Further, in the PV failure and faulty module bypass system of the photovoltaic power generation apparatus, the control apparatus obtains an average value and a standard deviation of the power, temperature, and TEV voltage of each PV module, and uses the average value and the standard deviation Determining a failure and a defective range having a predetermined value or less in a normal distribution curve expressed by the probability density function, and calculating a power density, a temperature, and a TEV voltage falling within the failure and failure range And the detected PV module is determined as a failure and a failure module.

Further, in the PV failure and bad module bypass system of the photovoltaic power generation apparatus, the control apparatus determines whether the power P _i of the PV module falls within the above-mentioned failure and failure range and the power P _i of the PV module is half m _p / 2, the PV module temperature T _i or TEV voltage U _i falls within the above-mentioned failure and defect range and the temperature T _i of the PV module or the TEV voltage U _i If less than half of the m _t / 2 or the average value of the average half _u m / 2, characterized in that to determine the PV module to a failure and failure.

As described above, according to the PV failure and faulty module bypass system of the photovoltaic power generation apparatus according to the present invention, by monitoring each photovoltaic module (PV module) and detecting and bypassing the faulty and defective modules, Monitoring and replacement of defective modules can be managed, thereby achieving the effect that the solar power generation maintains normal efficiency and operation continuously.

Further, according to the PV failure and faulty module bypass system of the photovoltaic power generation apparatus according to the present invention, the failure and the bad module are determined using the deviation of the power, temperature, and discharge voltage of each PV module, It is possible to more accurately detect the faulty and faulty module even if the internal temperature of the PV module rises or the discharge voltage rises due to the rapid fluctuation of the sunlight amount depending on the atmospheric conditions such as humidity, Loses.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a configuration of a PV failure and a bad module bypass system of a solar power generation apparatus according to an embodiment of the present invention; FIG.
2 is a configuration diagram of a control apparatus according to an embodiment of the present invention;
3 is a circuit diagram of an MCU according to an embodiment of the present invention;
4 is a circuit configuration diagram of a bypass module according to an embodiment of the present invention;
5 is a block diagram of a configuration of a sensor module according to an embodiment of the present invention;
6 is a circuit diagram of a power sensor according to an embodiment of the present invention;
7 is a circuit diagram of a temperature sensor according to an embodiment of the present invention;
8 is a graph showing waveforms and magnitudes of transient ground voltage according to an embodiment of the present invention.
9 is a circuit diagram of a TEV sensor according to an embodiment of the present invention.
10 is a structural view of a capacitive probe of a TEV sensor according to an embodiment of the present invention.
11 is an equivalent circuit diagram of a TEV sensor according to an embodiment of the present invention.
FIG. 12 is a flowchart illustrating a method for determining whether a PV module fails and is defective according to an exemplary embodiment of the present invention. FIG.
13 is a graph showing normal distribution curves and failure and failure ranges for power, heating temperature, and TEV voltage, respectively, according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings.

In the description of the present invention, the same parts are denoted by the same reference numerals, and repetitive description thereof will be omitted.

First, a configuration of a PV failure and a defective module bypass system of a photovoltaic power generation apparatus according to an embodiment of the present invention will be described with reference to FIG.

1, the photovoltaic power generation system for practicing the present invention includes a photovoltaic power generation apparatus 10 composed of a PV module 11, bypassing each PV module 11, A sensor module 30 installed in each PV module 11 and measuring the power, temperature and transient ground voltage of the corresponding PV module 11, And a control unit 40 for analyzing the measured value of the sensor module 30 to detect a failure and failure module and to control the bypass of the bypass module 20. Further, the output of the photovoltaic device 10 is connected to a connection part or an inverter.

The photovoltaic power generation apparatus 10 is composed of a plurality of PV modules (solar cell modules) 11.

Each PV module 11 is composed of a plurality of solar cells (not shown) as in the conventional solar cell module. Each solar cell generates power by the photovoltaic effect when sunlight is applied, and each of the PV modules 11 composed of a plurality of solar cells merges and outputs power generated in the solar cells.

The PV module 11 is for generating electricity by condensing solar light incident from the outside, and silicon and a composite material are usually used mainly. Specifically, the PV module 11 uses a P-type semiconductor and an N-type semiconductor bonded together, and uses the photoelectric effect to generate electricity by receiving sunlight. Most of the PV modules 11 are formed of large-area P-N junction diodes, and the electromotive force generated at the opposite ends of the P-N junction diode is connected to an external circuit. The minimum unit of the PV module 11 is referred to as a cell. Actually, the solar cell is rarely used as it is. This is because the voltage required from one cell is very small, about 0.5V, compared to several tens of V or several hundreds of V, which is necessary for practical use. Therefore, a plurality of unit solar cells can be connected in series or parallel . In addition, when the photovoltaic device 10 is used outdoors, it is subjected to various harsh environments. Therefore, a plurality of cells are used as a package in order to protect a plurality of cells connected with a necessary unit capacity in a harsh environment.

The bypass module 20 includes a plurality of bypass circuits 21 corresponding to the plurality of PV modules 11 and a relay 22 for switching the bypass circuit 21. If the control device 40 determines that each PV module 11 is normal and, if the PV module 11 is normal, supplies the accumulated power to the next PV module 11, and if the PV module 11 is abnormal, 21).

That is, the bypass circuit 21 is a circuit provided to correspond to each PV module 11, and is a circuit for directly connecting or bypassing each PV module 11 in series with the adjacent PV module 11. The bypass circuit 21 is controlled by the control device 40 to selectively control the direct connection or the bypass connection. The selective control is operated by the switching of the relay (or relay). That is, the control device 40 controls the relay 22 to directly connect or bypass the bypass circuit 21.

Next, the sensor module 30 is installed in each of the PV modules 11 to measure the power, temperature, transient ground voltage, etc. of the corresponding PV module 11. That is, one sensor module 30 corresponds to one PV module 11. The sensor module 30 is composed of circuits for detecting power, temperature, transient ground voltage, and the like. The power, temperature, transient ground voltage, etc. measured by the sensor module 30 are transmitted to the control device 40 and used to detect whether the PV module 11 is malfunctioning or not.

Next, the control device 40 receives (or brings in) the measured values from the sensor module 30, and uses the measured values to determine whether each PV module 11 is faulty or defective. That is, the controller 40 receives the measured power, temperature, transient ground voltage, and the like from the sensor module 30. Then, the controller 40 determines the distribution of the power, the temperature, and the excessive ground voltage, and detects the PV module 11 deviating from the predetermined distribution range as failure and failure.

Further, the control device 40 instructs the bypass module 20 to bypass the PV module 11 determined to be faulty or defective. That is, the control device 40 controls the bypass circuit 21 of the faulty and defective PV module 11 to bypass the PV module 11, thereby removing the corresponding PV module 11 from the series connection. Specifically, if it is determined that the PV module 11 is a failure and a faulty module, the bypass path is formed such that the corresponding PV module is excluded from the connection of the plurality of PV modules 11 of the photovoltaic power generation device. If it is determined that the PV module 11 is normally operating, an electrical connection path is formed in series with the adjacent solar cell modules.

In other words, the controller 40 controls the bypass module 20 to electrically connect each PV module 11 to an adjacent PV module 11 or to provide a bypass path not to be connected to an adjacent PV module 11, (20).

Next, the output from the photovoltaic device 10, that is, the direct current, is collected in a connection unit (not shown) and output to an inverter (not shown).

A connection unit (not shown) is provided for connecting a plurality of solar power generation apparatuses 10 in series or in parallel. In addition, the connection panel is equipped with a DC power switch, an output terminal switch, a molded case circuit breaker (MCCB), a bus bar or a terminal block, and a safety switch such as a magnetic switch, a diode and a power fuse, Devices for delivery may be provided.

An inverter (not shown) integrates the DC power received from the solar cell generator 10 in parallel into one DC power and converts it into AC power for use as commercial power. The AC power output from the inverter is supplied to the load of the consumer through the power system or water generators.

Next, the configuration of the control device 40 according to one embodiment of the present invention will be described in more detail with reference to FIG. 2 to FIG.

2, the control apparatus 40 according to the present invention includes a sensor receiving section 41 for receiving measured data or detected values from the sensor module 30, a relay 22 for the bypass module 20, A control signal unit 42 for transmitting a control signal, and a control unit 43 such as an MCU for determining whether each PV module 20 is faulty or defective by using the received detection value or measured value. In addition, it may further comprise a display unit 44 for displaying the current state of the photovoltaic device or a warning or an alarm on the screen, or a data transmission unit 45 for transmitting the current state or the like to a terminal of a remote server or an administrator .

The sensor receiving unit 41 receives the power, temperature, and transient ground voltage of each PV module 11. At this time, the sensor receiving unit 41 receives power, temperature, transient ground voltage, and the like using a normal serial communication method such as RS-485 communication.

Or the control signal unit 42 is connected to the relay 22 of each bypass circuit 21 by a signal line and transmits each control signal to each relay 22. The control signal is an on / off signal, which is a signal for turning on or off the relay, respectively.

The MCU 43 is a processor that performs a control function by performing a program according to a program, and is formed of a microcontroller such as an MCU and a microprocessor. The MCU 43 stores the faulty and bad module determination program in a storage medium such as a ROM or a flash memory, and executes the program to determine whether each PV module is faulty or defective.

That is, the MCU 43 includes a microcontroller or a microprocessor, and has a program for collecting power, temperature, and excessive ground voltage of each PV module to determine whether there is a failure or a bad module. Then, the controller 40 causes the MCU 43 such as a microprocessor to execute the faulty and bad module determination program, thereby performing the faulty and bad module detection and bypass operation.

In addition, the MCU 43 commands the operation of the relay by bypassing the bypass module 20 when a fault and a faulty module occur, and generates an alarm to the outside to allow the manager to take measures accordingly.

In particular, the MCU 43 may include a microcontroller as shown in FIG. In Figure 3, pin PB0 of the MCU is used as an external surge interrupt and is designed to ignore data when an interrupt occurs. Also, the pin PA0 (TEMP_A / D) is used as the A / D input of the temperature sensor (TMP-36).

In addition, the LCD can be used within the -30 ° C to + 80 ° C range with OTM803 (OPTIMA ENC). Pin PK1 is also used for temperature alarm output (RED-LED) and pin PK2 is used for TEV alarm output (RED-LED). In addition, PK3 and PK4 are lit in the operation mode (GREEN-LED in normal mode) and in event mode, respectively. An unused port can be used as an output port.

The display unit 44 displays a current status of the solar power generation apparatus 10 as a display such as an LCD. For example, the total number of PV modules and the number of faulty and bad modules are displayed. Or one PV module as a point to mark the entire PV as a matrix, the normal PV modules are marked in blue, and the faulty and bad PV modules are marked in red. That is, different colors can be used to visually display faulty and faulty modules at a glance.

In addition, the data transfer unit 45 transmits the detected values such as the measured power, temperature, transient ground voltage, and the failure and the defective state of each PV module wirelessly or by wire. Or the data transfer unit 45 transmits the failure and faulty status of the PV module to the mobile terminal or the server of the administrator.

Next, a configuration of the bypass module 20 according to an embodiment of the present invention will be described with reference to FIG.

As shown in FIG. 4, the bypass module 20 includes a bypass circuit 21 that operates as a kind of switch, and a relay 22 that operates switching. The relay 22 is operated by the control of the control device 40, and the switch of the bypass circuit 21 is operated. On the other hand, the control signal is a signal driven by a command transmitted from the control device 40.

Specifically, when the switch is connected to the bottom by the relay, the current PV module is connected in series with the immediately adjacent PV module. However, when the switch is connected to the top by the relay, the current PV module bypasses the adjacent PV module.

The controller 40 receives the measured power, temperature, transient ground voltage, etc. from the sensor module 30 and determines whether the PV module 11 is faulty or defective based on the distribution of power, temperature, do. That is, when the abnormal condition of the PV module occurs, the controller 40 secures the bypass path through the relay.

The bypass circuit operation time detects the sensor abnormal condition of the terminal box so that the operation time of the bypass relay becomes 0.5 seconds or less.

Next, a sensor module 30 according to an embodiment of the present invention will be described with reference to FIG.

5, the sensor module 30 includes a power sensor 31 for detecting the power of the corresponding PV module 11, a temperature sensor 32 for detecting the temperature of the heat generated in the corresponding PV module 11, And a TEV sensor 33 for measuring a transient earth voltage (TEV). In addition, the control unit 40 may further include a communication unit 35 for transmitting measured values measured by the respective sensors to the control unit 40.

The sensor module 30 attaches a sensor to the outside of the terminal box of the PV module to detect a temperature rise and an excessive grounding voltage, measures electric power, and transmits / receives information to / from the control device 40 by RS-485 communication. One sensor module (30) is attached to the module terminal box per PV module (11), and it is used in connection with the existing PV terminal box. (+, -) communication (D +, D-) by the RS-485 communication. The sub module operation such as various sensors monitors the temperature and power of each PV module.

In addition, the sensor module 30 normally scans each sensor (or detection circuit), communicates with the control device 40, and lights the OPER_GRN lamp.

The power sensor 31 detects the power generated by solar power generation in the corresponding PV module 11. The power of the PV module 11 due to the solar power generation is influenced by the solar radiation and the temperature of the sun. That is, when the solar radiation amount increases, the power of the PV module 11 increases in proportion thereto.

The temperature sensor 32 is installed on the surface of the corresponding PV module 11 or on the surface of the terminal box, and measures the temperature generated by the PV module 11. The heat generated in the PV module 11 is internally generated heat of the PV module 11. That is, the PV module 11 internally generates heat due to internal defects or excessive reaction, and the temperature may rise. Further, the temperature of the internal heat is affected by the temperature of the surrounding environment or the solar radiation. That is, the internal heat generation of each of the PV modules 11 may be increased or decreased depending on the solar radiation amount or the surrounding environmental temperature.

The TEV sensor 33 is installed in the corresponding PV module 11 and measures the surface current caused to the outside such as the surface of the PV module 11 by discharge. Particularly, the TEV sensor 33 can measure the surface current caused by the arc discharge generated in the PV module 11 and measure the current caused by the partial discharge generated in the PV module 11 have. Therefore, the TEV sensor 33 can detect not only the arc discharge but also the partial discharge. The frequency of the electromagnetic wave stimulated by the arc discharge pulse is in the range of tens MHz to several hundred MHz.

The transient ground voltage TEV can be detected by the TEV sensor 33 which is generated in the terminal housing metal housing of each PV module 11 and installed on the surface. When arc discharge occurs inside the terminal box, high frequency electromagnetic waves due to the discharge occur on the surface of the metal wall, causing a surface current. The TEV sensor can be mounted on the outer surface of the terminal box to detect the pulse voltage (transient ground voltage signal). Therefore, the transient ground voltage generated by the surface current due to the arc discharge occurring in the terminal box is detected.

If a transient earth voltage for an arc discharge occurs between the object and ground, the ground voltage will change instantaneously and temporarily. Therefore, monitoring of Transient Earth Voltage (TEV) may be effective in detecting and evaluating the discharge and to prevent problems and hazards caused by discharging.

Next, the configuration of the power sensor 31 according to one embodiment of the present invention will be described with reference to FIG.

6, the power sensor 31 according to the present invention includes a voltage sensor 31a for measuring a voltage, a current sensor 31b for measuring a current, and power And a calculation unit 31c.

That is, the power sensor 31 measures the voltage and current of the individual PV module 11 to detect the power. If the detected power is relatively small compared to other modules, the controller 40 determines that the module is malfunctioning or defective. Thus, the relay is connected and connected through the bypass path.

Next, the configuration of the temperature sensor 32 according to an embodiment of the present invention will be described with reference to FIG.

As shown in FIG. 7A, the temperature sensor 32 according to the present invention includes a temperature detection circuit for detecting the temperature. When the temperature of the terminal box of the PV module is sensed using the semiconductor TMP-36 sensor, it is judged that the module is overheated or overdischarged and the relay is connected and connected through the bypass path.

Also, as shown in FIG. 7B, the temperature sensor 32 receives DC + 7.5V from the power source and converts the voltage to 5V for stable power supply.

Next, a configuration of a TEV sensor 33 according to an embodiment of the present invention will be described with reference to Figs. 8 to 11. Fig.

When an arc discharge occurs inside the PV module 11 or the module terminal box, high-frequency electromagnetic waves due to the discharge occur on the surface of the metal wall, causing a surface current. The TEV sensor can be mounted on the outer surface of the terminal box to detect the pulse voltage (transient ground voltage signal).

The time constant and relation curve of the TEV signal amplitude and the discharge power can be obtained as shown in FIG. 8A, when the time constant sigma of the excitation source increases to 50 ns, the TEV signal amplitude sharply decreases from 175.1 mV to 4.9 mV. As the time constant of the source pulse here increases, the pulse width increases. However, the detected TEV signal amplitude decreases. The higher the frequency of the partial discharge source is, the more the TEV signal on the surface of the terminal box becomes stronger. The simulation shows that the TEV signal intensity at the detection point in Fig. 8 is proportional to the pulse current amplitude of the discharge power source. The higher the pulse amplitude of the source here, the stronger the TEV signal on the terminal box surface.

When an arc occurs in the terminal box, the generated electromagnetic waves are generated by stimulating the TEV signal to the outer surface of the metal enclosure from the open connector and the lid and void space of the switch. TEV signal strength and the pulse characteristics of the arc discharge. The amplitude of the TEV signal is proportional to the amplitude of the discharge pulse. The amplitude of the TEV signal increases as the excitation frequency of the discharge pulse increases. The TEV signal propagates along the surface of the terminal box, creating a clear time delay.

A TEV detection equivalent circuit using a TEV sensor probe can be represented as shown in FIG. 9. The operation principle is to detect an electric field formed in the normal direction of the surface of the object to be measured by generating an arc discharge using a capacitive probe. The magnitude of the pulse due to the discharge is proportional to the cross-sectional area of the probe and the incident displacement current density, and the frequency response is determined by the detection impedance Z and the input impedance Z 'of the amplifier circuit.

As shown in Fig. 9, the TEV sensor 33 is composed of a capacitive probe, a coupling network, and a low-noise amplifier circuit. The planar capacitive probe of Fig. 10, in which the detection electrode can be installed parallel to the metal surface, is designed / manufactured.

A TEV sensor 33 probe was made of a copper plate with a thickness of 0.07 mm and an area of 56.5 cm 2 and a flame-retardant epoxy resin having a dielectric constant of 0.2 [mm] and a relative dielectric constant of 4 and an area of 150 [cm 2]. A coaxial cable with excellent high frequency characteristics and a characteristic impedance of 50 [Ω] was used for transmission of the detection signal, and a BNC connector was attached to the ground electrode surface for connection.

(90 to 100 [pF / m]) due to the insulator of the coaxial cable and the external conductor causes distortion of the transmission signal. Therefore, in order to eliminate the influence thereof, a matching resistor the R _m and the compensation resistance R _i which are configured as in Figure 11.

Terminal box Because TEV occurs on the metal surface in the form of high-frequency pulses with a rise time of 10 to 20 ns, a coupling network A _v consisting of the detection impedance and the input impedance of the amplifier circuit is required. A stable device should be used that does not cause burnout or discharge in the voltage range.

Next, a method for determining whether the PV module of the control device 40 is malfunctioning or not according to an embodiment of the present invention will be described with reference to Figs. 12 to 10. Fig.

12, the number of PV modules 11, the power read from the PV module i, P _i , the temperature T _i , and the TEV voltage U _i in the photovoltaic power generation system will be described.

Next, an average value of power, temperature, and TEV voltage is obtained.

[Equation 1]

Here, m _p , m _t, and m _u represent an average value of power, temperature, and TEV voltage, respectively.

Next, the deviation of the average value of the module and the power, temperature, and TEV voltage of each module is obtained.

&Quot; (2) "

Next, the standard deviation of the power, temperature, and TEV voltage is obtained.

&Quot; (3) "

Next, if the normal distribution N (m _p , σ _p ² ), N (m _t , σ _t ² ) and N (m _u , σ _u ² ) are followed, the probability density function is expressed by the following equation.

&Quot; (4) "

&Quot; (5) "

&Quot; (6) "

FIG. 13 is a diagram showing the normal distribution curves of Equations (4), (5) and (6).

The probability of belonging to the painted part (hereinafter referred to as failure and defect range) in the normal distribution curve with respect to the power, temperature, and TEV voltage expressed in FIG. 13 is expressed by the following equation.

&Quot; (7) "

If the failure and failure range is reached and the power P _i of each module is less than half the average value m _p / 2, or if the temperature T _i , TEV voltage U _i of each module is half of the mean value m _t / 2, m _u / 2, it is determined that the module outputs a significantly lower power, a higher heating temperature, or a TEV voltage than the peripheral module due to failure or failure.

If it is judged to be faulty or defective, an alarm message is sounded and the relay of the bypass path for the PV module Mod _i is switched so that current flows through the bypass path. If this phenomenon occurs continuously for the module, it can be managed so that the solar power generation can be continuously and stably operated by replacing the corresponding module.

Although the present invention has been described in detail with reference to the above embodiments, it is needless to say that the present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the spirit of the present invention.

10: Photovoltaic device 11: PV module
20: Bypass module 21: Bypass circuit
22: Relay 30: Sensor module
31: power sensor 32: temperature sensor
33: TEV sensor 35:
40: control device 41: sensor receiver
42: control signal part 43: MCU
44: Display unit 45: Data transfer unit

Claims (5)

In PV failure and faulty module bypass systems of photovoltaic devices,
A photovoltaic device comprising a plurality of PV modules connected in series;
A bypass module installed in each of the PV modules and configured to bypass the PV modules;
A temperature sensor installed in each of the PV modules for measuring a power of the corresponding PV module, a temperature sensor for measuring a temperature of the PV module, and a TEV detecting unit for detecting a transient ground voltage (TEV) A sensor module comprising a sensor; And
And a control unit that receives a detection value from the sensor module, calculates a power of the corresponding PV module based on the detected power value, obtains a probability distribution of the detected power, temperature, and transient ground voltage, If the detected value of the power distribution is within a predetermined range from the probability distribution, the command is transmitted to the bypass module so as to bypass the corresponding bypass module, And bypasses if the detection value of the temperature and transient ground voltage is equal to or greater than a predetermined range,
The controller obtains an average value and a standard deviation of the power, temperature, and TEV voltage of the entire PV module, obtains a probability density function along a normal distribution using the average value and the standard deviation, calculates a normal distribution represented by the probability density function Determining a fault and a failure range having a predetermined value or less in a curve and determining a PV module detected by power, temperature, and TEV voltage falling within the failure and failure range as a failure and a failure module,
The control device when the power P _i of the PV module is entered in the breakdown and failure ranges the power P _i of the PV module is less than half of the average value m _p / 2, determining the PV modules to malfunction or failure, and PV module the temperature T _i and TEV voltage U, if _i is the breakdown and into the poor range the temperature of the PV module, T _i or TEV voltage U _i is less than half of the m _t / 2 or the average value of the average half m _u / 2, the If the PV module is judged to be faulty or defective,
Wherein the control unit determines that the power P _i , the temperature T _i , and the TEV voltage U _i of the PV module satisfy the following equation (1) Path system.
[Equation 1]

Σ _p , σ _t , and σ _u are the standard deviations of the power, temperature, and TEV voltage of the entire PV module, respectively, and m _p , m _t and m _u are the average values of the power, , k is a constant greater than zero.
The method according to claim 1,
Wherein the bypass module includes a bypass circuit for directly connecting or bypassing the output of the installed PV module with an adjacent PV module and a relay for switching the bypass circuit to receive an instruction from the control device And controls the relay of the bypass circuit to control the direct connection or the bypass connection of the PV module.
The method according to claim 1,
The control device includes a microprocessor, and has a program for receiving the power, temperature, and TEV voltage of each PV module transmitted by the RS-485 communication with the sensor module and determining whether the PV module is faulty or defective And the malfunctioning and malfunctioning module determination program is executed by the microprocessor, thereby performing the malfunctioning and defective module detection and bypassing operation.
delete delete

Images