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WO2016031269A1 - Dispositif de détection de défaut à la terre et procédé de détection de défaut à la terre - Google Patents

Dispositif de détection de défaut à la terre et procédé de détection de défaut à la terre Download PDF

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Publication number
WO2016031269A1
WO2016031269A1 PCT/JP2015/055264 JP2015055264W WO2016031269A1 WO 2016031269 A1 WO2016031269 A1 WO 2016031269A1 JP 2015055264 W JP2015055264 W JP 2015055264W WO 2016031269 A1 WO2016031269 A1 WO 2016031269A1
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WIPO (PCT)
Prior art keywords
ground fault
solar cell
path
voltage
current path
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PCT/JP2015/055264
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English (en)
Japanese (ja)
Inventor
康介 森田
誠 井手
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オムロン株式会社
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Publication of WO2016031269A1 publication Critical patent/WO2016031269A1/fr

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
    • G01R31/52—Testing for short-circuits, leakage current or ground faults
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02S—GENERATION OF ELECTRIC POWER BY CONVERSION OF INFRARED RADIATION, VISIBLE LIGHT OR ULTRAVIOLET LIGHT, e.g. USING PHOTOVOLTAIC [PV] MODULES
    • H02S50/00—Monitoring or testing of PV systems, e.g. load balancing or fault identification
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy

Definitions

  • the present invention relates to a ground fault detection device and a ground fault detection method for detecting a ground fault of a solar cell.
  • a solar cell string that generates power using sunlight is formed by connecting a plurality of solar cell panels (solar cell modules) in series, and a solar cell panel is formed by connecting a plurality of solar cells in series. ing.
  • the electric power generated by the solar cell string is supplied to the electric power transmission network through the power conditioner.
  • the solar cell string is in a floating state without being grounded, and a ground fault occurs when the insulation resistance decreases for some reason. Therefore, conventionally, as disclosed in Patent Document 1, a solar cell string is provided with a ground fault detection device that detects the occurrence of a ground fault.
  • the ground fault detection device 102 disclosed in Patent Document 1 includes first and second switches 111 and 112, a detection resistor R111, a voltage detector 114, and an arithmetic control unit 115.
  • the positive electrode of the solar cell string 101 is grounded via the first switch 111 and the detection resistor R111, and the negative electrode is grounded via the second switch 112 and the detection resistor R111. It has come to be.
  • the first and second switches 111 and 112 are connected to the terminals on the detection resistor R111 side. Therefore, when the first switch 111 is on and the second switch 112 is off, the first voltage V111 is generated across the detection resistor R111, and the first switch 111 is off and the second switch 112 is on. Generates a second voltage V112 across the detection resistor R111.
  • the voltage detector 114 detects the first and second voltages V111 and V112 at both ends of the detection resistor R111, and detects a voltage between the positive electrode and the negative electrode of the solar cell string 101.
  • the arithmetic control unit 115 controls the on / off operation of the first and second switches 111 and 112, and is based on the first and second voltages V111 and V112, the voltage between the electrodes, and the resistance value of the detection resistor R111.
  • a ground fault resistance value (insulation resistance value) of the string 101 is obtained.
  • JP 2012-119382 A (published on June 21, 2012)
  • the first and second switches 111 and 112 are both turned on, for example, the first and second switches 111 and 112 are both welded in the on state.
  • the positive electrode and the negative electrode of the solar cell string 101 are short-circuited, and a large current flows through a circuit between the positive electrode and the negative electrode. In such a case, the circuit generates heat and may cause a fire.
  • the first and second switches 111 and 112 in the power feeding path between the first and second switches 111 and 112 and the solar cell string 101 are used. It is conceivable to provide protective resistors R112 and R113 in series with each other. In such a configuration, even when both the first and second switches 111 and 112 are turned on, the current flowing through the circuit between the positive electrode and the negative electrode of the solar cell string 101 is reduced, and the circuit Heat generation can be suppressed.
  • the protective resistances R112 and R113 which are resistors, have some errors in their resistance values due to manufacturing errors even if the indicated resistance values are the same. Further, the resistance values of the protective resistors R112 and R113 change due to temperature changes. This change in resistance value is not the same between the protective resistors R112 and R113, and there are individual differences. In other words, the temperature coefficient of the resistance value differs between the protective resistors R112 and R113. Among these, the error of the resistance value at the time of manufacture can be dealt with by the initial adjustment. However, the change in resistance value due to temperature cannot be accommodated by the initial adjustment.
  • the first switch 111 is turned on and the second switch 112 is turned off, the first voltage V111 obtained through the protection resistor R112, and the first switch 111 is turned off and the second switch 112 is turned on, and the protection resistor The second voltage V112 obtained through R113 is inaccurate.
  • the ground fault resistance value of the solar cell string 101 obtained by using the first and second voltages V111 and V112 is inaccurate.
  • an object of the present invention is to provide a ground fault detection device and a ground fault detection method capable of obtaining a ground fault resistance value of a solar cell safely and with high accuracy.
  • a ground fault detection device of the present invention includes a detection resistor and a measurement unit, and the measurement unit acquires a voltage generated at both ends of the detection resistor to obtain a ground fault of a solar cell.
  • the ground fault detection apparatus for measuring the resistance value of the solar cell a first current path connected to the positive electrode of the solar cell, a second current path connected to the negative electrode of the solar cell, and the detection resistor at one end side
  • a first switching unit that switches between a first energizing path and a third energizing path provided between the first energizing path and a ground energizing path that is grounded at one end of the third energizing path.
  • a second switching unit that switches the connection on the other end side of the third energization path between the ground energization path and the second energization path.
  • the ground fault resistance of the solar cell can be obtained safely and with high accuracy.
  • FIG. 3 is a circuit diagram showing a state in a case where an interelectrode voltage of a solar cell string used for measurement of a ground fault resistance value is obtained in the photovoltaic power generation system shown in FIG. 2.
  • FIG. 3 is a circuit diagram illustrating a state in which a first voltage used for measurement of ground fault resistance is obtained in the photovoltaic power generation system illustrated in FIG. 2.
  • FIG. 3 is a circuit diagram showing a state in which a second voltage used for measuring a ground fault resistance value is obtained in the photovoltaic power generation system shown in FIG. 2. It is a circuit diagram at the time of rewriting the circuit of the photovoltaic power generation system at the time of calculating
  • FIG. 12 is a circuit diagram showing a state in which the first and second switches are turned on in the ground fault detection device shown in FIG. 11.
  • FIG. 13 is a circuit diagram showing a configuration when a protective resistor is provided in the ground fault detection device shown in FIG. 12.
  • FIG. 1 is a schematic circuit diagram showing a basic configuration of a solar power generation system 1 including a ground fault detection device according to an embodiment of the present invention.
  • the photovoltaic power generation system 1 includes a solar cell string 11, a ground fault detection device 12, and a power conditioning system (hereinafter referred to as PCS) 13.
  • PCS power conditioning system
  • the electric power generated by the solar cell string 11 is output to the power energization paths 15 a and 15 b and is supplied to the power transmission network 14 via the PCS 13.
  • the ground fault detection device 12 includes a power energization path changeover switch 21, an inspection first energization path (first energization path) 22a, an inspection second energization path (second energization path) 22b, and an inspection first changeover switch (first switching unit). ) 23, a second inspection switch (second switching unit) 24, a third inspection current path 25, a ground current path 26, a detection resistor R 1, and a controller (measurement unit) 27.
  • the power energizing path changeover switch 21 switches the connection of the power energizing paths 15a and 15b between the PCS 13 side and the inspection first and second energizing paths 22a and 22b side.
  • the inspection first changeover switch 23 is connected to one end of the inspection third energization path 25 and switches the connection of one end of the inspection third energization path 25 between the inspection first energization path 22 a and the ground energization path 26.
  • the inspection second changeover switch 24 is connected to the other end of the inspection third energization path 25, and connects the other end of the inspection third energization path 25 between the inspection second energization path 22 b and the ground energization path 26. Switch.
  • the ground energization path 26 is grounded.
  • the detection resistor R1 is provided between one end and the other end of the inspection third energization path 25.
  • the controller 27 controls the switching operation of the power conduction path switching switch 21, the inspection first switching switch 23, and the inspection second switching switch 24, and obtains the ground fault resistance value and the ground fault position of the solar cell string 11.
  • the controller 27 causes the power energization path changeover switch 21 to be connected to the inspection first and second energization paths 22a and 22b during the measurement operation of the ground fault detection device 12. The state is switched.
  • the controller 27 detects that the inspection first changeover switch 23 is switched to the inspection first energization path 22a and the inspection second changeover switch 24 is switched to the inspection second energization path 22b (corresponding to FIG. 3). A voltage generated between both ends of the resistor R1 is obtained, and an interelectrode voltage Va-Vb which is a voltage between the positive and negative electrodes of the solar cell string 11 is obtained.
  • the controller 27 sets the inspection first changeover switch 23 to the inspection first energization path 22a and the inspection second changeover switch 24 to the ground energization path 26 (corresponding to FIG. 4), and detects the detection resistor R1.
  • the first voltage V ⁇ b> 1 generated at both ends is acquired.
  • the controller 27 sets the inspection first changeover switch 23 to the ground energization path 26 and the inspection second changeover switch 24 to the inspection second energization path 22b (corresponding to FIG. 5), and detects the detection resistor R1.
  • the second voltage V ⁇ b> 2 generated at both ends is acquired.
  • the controller 27 obtains the ground fault resistance value (insulation resistance value) and the ground fault position of the solar cell string 11 based on the acquired inter-electrode voltage Va-Vb and the first and second voltages V1, V2. Details thereof will be described later.
  • FIG. 2 is a circuit diagram showing a specific configuration of solar power generation system 1 including ground fault detection device 12 according to the embodiment of the present invention, corresponding to the basic configuration shown in FIG. FIG. 2 shows a state where the power generated by the solar cell string 11 is supplied to the PCS 13 and the ground fault detection device 12 is not performing a measurement operation (power output state).
  • the solar cell string 11 includes a plurality of solar cell modules 31 connected in series.
  • Each solar cell module 31 includes a plurality of solar cells (not shown) connected in series, and is formed in a panel shape.
  • voltage dividing resistors R2 and R3 are provided between the detection resistor R1 and the inspection first changeover switch 23, and between the inspection resistor R1 and the inspection second changeover switch 24, Voltage dividing resistors R4 and R5 are provided.
  • the voltage across the detection resistor R1 is input to the controller 27 via the comparator 33. It is assumed that the resistance value of the detection resistor R1 is lower than the resistance values of the voltage dividing resistors R2 to R5.
  • the voltage dividing resistors R2 to R5 lower the first and second voltages V1 and V2 generated at both ends of the detection resistor R1, thereby reducing the voltage input to the controller 27.
  • the controller 27 can be configured by a microcomputer, and the ground fault detection device 12 can be miniaturized.
  • the voltage dividing resistors R2 to R5 exist in any of a circuit for obtaining the interelectrode voltage Va-Vb, a circuit for obtaining the first voltage V1, and a circuit for obtaining the second voltage V2. .
  • a current sensor 32 that detects the amount of current flowing through the power conduction path 15a is provided in the power conduction path 15a. Therefore, the current sensor 32 detects the generated current of the solar cell string 11.
  • the controller 27 measures the power generation amount (change value) of the solar cell string 11 based on the power generation current detected by the current sensor 32.
  • FIG. 3 is a circuit diagram showing a state in the case of obtaining the interelectrode voltage Va-Vb in the photovoltaic power generation system 1 shown in FIG.
  • FIG. 4 is a circuit diagram showing a state when the first voltage V1 is obtained in the photovoltaic power generation system 1 shown in FIG.
  • FIG. 5 is a circuit diagram showing a state when the second voltage V2 is obtained in the photovoltaic power generation system 1 shown in FIG.
  • the controller 27 switches the power supply path changeover switch 21 from the power output state shown in FIG. It switches so that 15b may be connected with test
  • the controller 27 connects the inspection first changeover switch 23 with one end of the inspection third energization path 25 to the inspection first energization path 22 a, and connects the inspection second changeover switch 24 with the other end of the inspection third energization path 25. Is switched to be connected to the inspection second energization path 22b.
  • both positive and negative poles of the solar cell string 11 are connected via the detection resistor R1 and the voltage dividing resistors R2 to R5.
  • a voltage corresponding to the resistance value of the detection resistor R1 when the voltage between the positive and negative of the solar cell string 11 is divided by the detection resistor R1 and the voltage dividing resistors R2 to R5 is generated at both ends of the detection resistor R1.
  • This voltage is taken into the controller 27 via the comparator 33, and the controller 27 obtains the interelectrode voltage Va-Vb.
  • the controller 27 performs the inspection first in a state where the power conduction paths 15a and 15b are connected to the inspection first and second conduction paths 22a and 22b.
  • the changeover switch 23 is switched so that one end of the inspection third energization path 25 is connected to the inspection first energization path 22a, and the inspection second changeover switch 24 is switched to the ground energization path 26 of the other end of the inspection third energization path 25. Switch to be connected to.
  • the positive electrode (P terminal) of the solar cell string 11 is grounded via the detection resistor R1 and the voltage dividing resistors R2 to R5.
  • both ends of the detection resistor R1 correspond to the resistance value of the detection resistor R1 when the voltage between the positive electrode of the solar cell string 11 and the ground potential is divided by the detection resistor R1 and the voltage dividing resistors R2 to R5.
  • the first voltage V1 is generated.
  • the first voltage V1 is taken into the controller 27 via the comparator 33, and the controller 27 obtains the first voltage V1.
  • the controller 27 performs the first inspection in the state where the power conduction paths 15a and 15b are connected to the first and second conduction paths 22a and 22b.
  • the changeover switch 23 is switched so that one end of the inspection third energization path 25 is connected to the ground energization path 26, and the other end of the inspection third energization path 25 is switched to the inspection second energization path 22b. Switch to be connected to.
  • the negative electrode (N terminal) of the solar cell string 11 is grounded via the detection resistor R1 and the voltage dividing resistors R2 to R5.
  • both ends of the detection resistor R1 correspond to the resistance value of the detection resistor R1 when the voltage between the negative electrode of the solar cell string 11 and the ground potential is divided by the detection resistor R1 and the voltage dividing resistors R2 to R5.
  • a second voltage V2 is generated.
  • the second voltage V2 is taken into the controller 27 via the comparator 33, and the controller 27 obtains the second voltage V2. Note that the order of obtaining the interelectrode voltage Va-Vb, the first voltage V1, and the second voltage V2 is in no particular order.
  • the controller 27 calculates
  • the solar cell string 11 is obtained by connecting five solar cell modules 31 in series, and the ground fault is the third solar cell modules 31 and 4 when viewed from the P terminal side of the solar power generation system 1. It is assumed that it occurs between the individual solar cell modules 31.
  • Reference numeral 34 denotes a ground fault resistance 34 at the ground fault position.
  • the ground fault detection device 12 of the photovoltaic power generation system 1 of the present embodiment all (four types) switching of the inspection first and second change-over switches 23 and 24 shown in FIGS.
  • the positive and negative poles of the solar cell string 11 are not short-circuited. That is, even in a switching pattern in which the positive and negative poles of the solar cell string 11 are connected, at least the detection resistor R1 is interposed between the positive and negative poles. Therefore, for example, even when a failure occurs in which the inspection first and second change-over switches 23 and 24 are welded at any one of the switching positions, a large current flows through the circuit of the photovoltaic power generation system 1 and the circuit is An excessive heat generation can be prevented.
  • ground fault resistance value (insulation resistance value)
  • a circuit including the same detection resistor R1 and the same voltage dividing resistors R2 to R5 is used, and the interelectrode voltage Va-Vb and the first and second voltages are used. V1 and V2 are measured. Accordingly, it is possible to eliminate the occurrence of measurement errors due to differences in resistance values and temperature coefficients during the individual manufacturing of the detection resistor R1 and the voltage dividing resistors R2 to R5. Thereby, the resistance value of the ground fault resistance 34 can be measured accurately.
  • the controller 27 when the controller 27 is constituted by a microcomputer, only one input port is required for measuring the interelectrode voltage Va-Vb and the first and second voltages V1, V2. Well, the number of ports required for the controller 27 can be reduced.
  • the voltage dividing resistors R2 to R5 are provided in series with the detection resistor R1, when the controller 27 is configured by a microcomputer, the voltage input to the controller 27 can be easily lowered to an appropriate voltage. it can.
  • the photovoltaic power generation system 1 may have a configuration in which a plurality of solar cell strings 11 are connected to the PCS 13 and the ground fault detection device 12 is provided for each of the plurality of solar cell strings 11.
  • the solar power generation system 1 may be configured such that only one ground fault detection device 12 is provided for the plurality of solar cell strings 11 and is switched to the plurality of solar cell strings 11. Good.
  • FIG. 8 A modification of the photovoltaic power generation system 1 shown in FIG. 2 is shown in FIG. In the configuration of FIG. 8, a protective resistor R11 is provided between the solar cell string 11 and the inspection first changeover switch 23, and a protective resistor R12 is provided between the solar cell string 11 and the inspection second changeover switch 24. Yes.
  • the conductor part of the solar cell string 11 which is in a floating state is made into other electroconductivity. Even when the member is touched, the amount of current flowing between the solar cell string 11 and the conductive member can be suppressed. Thereby, the safety
  • the protective resistors R11 and R12 are not used in common when the interelectrode voltage Va-Vb and the first and second voltages V1 and V2 are obtained.
  • the error cannot be completely cancelled.
  • the resistance values of the protection resistors R11 and R12 to a value smaller than the resistance value of the detection resistor R1, the adverse effect due to the presence of the protection resistors R11 and R12 is suppressed, and the safety of the photovoltaic power generation system 1 is improved. Can increase the sex.
  • the ground fault detection device 12 of the photovoltaic power generation system 1 performs a measurement operation (ground fault resistance value and ground fault position) when the power generation amount of the solar cell string 11 is small, such as early morning or evening. Measurement).
  • the controller 27 monitors the power generation amount of the solar cell string 11 based on the power generation current amount detected by the current sensor 32, and the power generation amount is within the range in which the measurement operation of the ground fault detection device 12 is possible (measurement). When it is within the range of possible values, the measurement operation is performed.
  • the configuration for determining the power generation amount of the solar cell string 11 is not limited to this, and the power generation amount detected by the current sensor 32 and the voltage between the positive and negative of the solar cell string 11 are determined. May be.
  • the upper limit of the range of the power generation amount that can be measured by the ground fault detection device 12 can be set, for example, based on the withstand voltage (power resistance) of each part of the ground fault detection device 12, and the lower limit value is, for example, The ground fault resistance value and the ground fault position can be set based on the lower limit value of the power generation amount that enables measurement of the ground fault position.
  • FIG. 9 is a graph showing changes in the open-circuit voltage and the power generation amount in the solar cell string on the day when the measurement operation is performed by the ground fault detection device 12. Between the sunrise and sunset of the place where the solar cell string 11 is installed, the open-circuit voltage and the power generation amount of the solar cell string 11 change as shown in FIG. 9, for example.
  • the range A indicates the operating range of the PCS 13.
  • the region B is a region included in the measurement operation possible range of the ground fault detection device 12 and exists in, for example, an early morning time zone in which the power generation amount (measurable value) of the solar cell string 11 is small. In the region B, the open circuit voltage of the solar cell string 11 reaches the vicinity of a predetermined maximum voltage. On the other hand, the amount of sunlight (change value) is small due to early morning, and the output current of the solar cell string 11 is a small value.
  • FIG. 10 is a flowchart showing the operation of the ground fault detection device 12.
  • the controller 27 monitors the power generation amount of the solar cell string 11 based on the power generation current amount detected by the current sensor 32 (S11), and the power generation amount of the solar cell string 11 is grounded. It is determined whether or not the measurement operation of the detection device 12 is within a possible range (S12). This determination is preferably performed after monitoring the power generation amount of the solar cell string 11 for a predetermined time.
  • the controller 27 switches the power conduction path switch 21 to the power conduction paths 15a and 15b. It switches so that it may connect with inspection 1st and 2nd electricity supply ways 22a and 22b (S13). Thereby, the power supply paths 15a and 15b from the solar cell string 11 to the PCS 13 are blocked.
  • the inspection first and second changeover switches 23 and 24 are switched to measure the ground fault resistance value and the ground fault position (S24), and the operation is ended when the measurement is completed.
  • the configuration for detecting when the power generation amount (change value) is small is not limited to monitoring the power generation amount of the solar cell string 11, but the time (change) such as early morning or evening by a clock (for example, a timer provided in the controller 27). (Value) may be referred to. Or the structure which refers to the amount of sunshine (change value) with a sunshine meter may be sufficient.
  • the change in the amount of sunshine is monitored for a predetermined time in order to eliminate the case where the amount of sunshine, that is, the amount of power generation decreases due to a temporary change in weather, and the amount of sunlight (power generation amount) It is preferable that the measurement operation is started after confirming that the time period is small.
  • the power generation amount, the time, and the amount of sunshine as change values are used to determine whether or not they are within a range in which the measurement operation of the ground fault detection device 12 can be performed (a range of measurable values).
  • a range in which the measurement operation of the ground fault detection device 12 can be performed a range of measurable values.
  • the ground fault detection device 12 is used. The measurement operation may be performed. In this case, the reliability of the measurement operation of the ground fault detection device 12 can be improved.
  • the ground fault detection device 12 is a measurement operation possible time zone in which the power generation amount of the solar cell string 11 is within a measurable value range and the time is set as a time zone in which the power generation amount is relatively small.
  • a measurement operation may be performed.
  • the measurement operation of the ground fault detection device 12 is started when the power generation amount of the solar cell string 11 is reduced due to a sudden deterioration of weather in a time zone in which the solar cell string 11 generates a large amount of power. After that, the weather suddenly recovers and the power generation amount of the solar cell string 11 increases, so that it is possible to prevent a situation in which the operation of the ground fault detection device 12 is hindered. Thereby, the reliability of the ground fault detection apparatus 12 can be improved.
  • the ground fault detection device 12 includes a sunshine meter that detects the amount of sunshine at the position of the solar cell string 11, the amount of power generation is within a measurable value range, and the amount of sunshine is equal to or less than a predetermined amount.
  • a measurement operation may be performed.
  • a part of the solar cell string 11 is covered with some coating in a time zone where the power generation amount of the solar cell string 11 is large (a state in which the amount of sunlight is large).
  • the measurement operation of the ground fault detection device 12 is performed, and a situation in which an inappropriate measurement result is obtained can be prevented.
  • the covering is removed during the measurement operation of the ground fault detection device 12 and the power generation amount of the solar cell string 11 is increased, thereby preventing a situation that hinders the operation of the ground fault detection device 12. be able to. Thereby, the reliability of the ground fault detection apparatus 12 can be improved.
  • the ground fault detection device 12 performs the measurement operation for the ground fault in the time zone when the power generation amount of the solar cell string 11 is small, the breakdown voltage required for the components of the ground fault detection device 12 is reduced. Can do. Accordingly, for example, small and inexpensive parts such as the inspection first and second change-over switches 23 and 24 made of a relay can be used, and the apparatus can be configured to be small and inexpensive.
  • the ground fault detection device 12 is configured to measure the ground fault resistance value of the solar cell string 11 when the power generation amount of the solar cell string 11 is small. Therefore, the situation where the power generation amount of the solar cell string 11 is reduced by the operation of the ground fault detection device 12 can be suppressed. About another function, it is the same as that of the case of the above-mentioned ground fault detection apparatus.
  • the ground fault detection device of the present invention includes a detection resistor and a measurement unit, and the measurement unit acquires a voltage generated at both ends of the detection resistor and performs a measurement operation of the resistance value of the ground fault of the solar cell.
  • a first energization path connected to the positive electrode of the solar cell
  • a second energization path connected to the negative electrode of the solar cell
  • the detection resistor provided between one end side and the other end side
  • a 1st switching part switches the connection of the one end side of a 3rd electricity supply path between a grounding electricity supply path and a 1st electricity supply path.
  • the second switching unit switches the connection on the other end side of the third energization path between the ground energization path and the second energization path.
  • a measurement part acquires the voltage which arises at the both ends of detection resistance, and measures the resistance value of the ground fault of a solar cell.
  • the first switching unit switches the connection on one end side of the third energization path to the first energization path, and the second switching unit changes the connection on the other end side of the third energization path to the second energization path.
  • an inter-electrode voltage which is a voltage between the positive and negative electrodes of the solar cell, generated at both ends of the detection resistor is acquired.
  • the first switching unit switches the connection on one end side of the third energizing path to the first energizing path
  • the second switching unit switches the connection on the other end side of the third energizing path to the ground energizing path.
  • the first voltage generated at both ends of the detection resistor is acquired.
  • the first switching unit switches the connection on one end side of the third energizing path to the ground energizing path
  • the second switching unit switches the connection on the other end side of the third energizing path to the second energizing path.
  • the second voltage generated at both ends of the detection resistor is acquired.
  • the measurement unit can obtain the resistance value of the ground fault of the solar cell from the inter-electrode voltage, the first voltage, the second voltage, and the resistance value of the detection resistor.
  • a 1st switching part and a 2nd switching part are switched, and the positive electrode and negative electrode of a solar cell are a 1st electricity path, a 1st switching part, a 3rd electricity path, and a 2nd switching.
  • the detection resistor provided in the third current path is always present. Become. Therefore, a situation where the positive electrode and the negative electrode of the solar cell are short-circuited does not occur, and a situation where a large current flows through the circuit and the circuit excessively generates heat can be prevented.
  • a voltage dividing resistor may be provided in series with the detection resistor in the third energization path.
  • the voltage dividing resistor is provided in series with the detection resistor in the third energization path, the voltage generated at both ends of the detection resistor can be divided by the voltage dividing resistor to be small.
  • produces at the both ends of detection resistance, and measures the resistance value of the ground fault of a solar cell can be comprised with a microcomputer, and size reduction of an apparatus can be accelerated
  • the voltage dividing resistor is also provided in the third current path in series with the detection resistor, the first and second switching units are switched to acquire a voltage necessary for measuring the resistance value of the ground fault. Commonly used in cases. Therefore, it is possible to eliminate the occurrence of ground fault resistance measurement errors due to differences in resistance values and temperature coefficients during the production of voltage divider resistors, and to maintain a highly accurate measurement function for ground fault resistance values. it can.
  • the ground fault detection apparatus includes a change value detection unit that detects a change value that is a value that affects the power generation amount of the solar cell or a power generation amount of the solar cell, and the measurement unit has the change value that is the solar power generation amount. It is good also as a structure which performs the said measurement operation
  • the change value detection unit changes a value that affects the power generation amount of the solar cell, for example, the time (early morning or evening time), the amount of sunlight at the position of the solar cell, or the power generation amount of the solar cell itself. Detect as value.
  • a measurement part performs the measurement operation
  • the withstand voltage (power resistance) required for the components of the ground fault detection device is reduced, and a small and inexpensive device such as a relay constituting the first and second switching units can be used, and the device is small and inexpensive. It can be set as a simple structure.
  • the solar cell is a solar cell string including a plurality of solar cell modules connected in series
  • the measurement unit includes a first switching unit on one end side of the third current path.
  • the first switching section switches the connection on one end side of the third energization path to the ground energization path
  • the second switching section switches the connection on the other end side of the third energization path to the second energization path.
  • the ground fault position can be measured in addition to the ground fault resistance value.
  • the ground fault detection method of the present invention is a ground fault detection method comprising a measuring step of measuring a resistance value of a ground fault of a solar cell by acquiring a voltage generated at both ends of a detection resistor, wherein the detection resistor is one end.
  • a first energizing path that is connected between one end of a third energizing path provided between the side and the other end side between a grounded energizing path that is grounded and a first energizing path that is connected to the positive electrode of the solar cell.
  • a configuration comprising a switching step and a second switching step for switching the connection on the other end side of the third energization path between the ground energization path and the second energization path connected to the negative electrode of the solar cell. It is.
  • the present invention can be used, for example, as a device for detecting a ground fault resistance value and a ground fault position of a photovoltaic power generation system including a photovoltaic string configured by connecting a plurality of photovoltaic modules in series.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
  • Photovoltaic Devices (AREA)

Abstract

　L'objectif de la présente invention est de mesurer la résistance de défaut à la terre d'une manière sûre et extrêmement précise. Dans ce dispositif de détection de défaut à la terre (12), un contrôleur (27) mesure la résistance de défaut à la terre. Un premier commutateur de test (23) commute la connexion d'une extrémité d'un troisième chemin de courant de test (25) ayant une résistance de détection (R1), la connexion étant commutée entre un chemin de courant à la terre (26) et un chemin de courant de test (22a). Un second commutateur de test (24) commute la connexion de l'autre extrémité du troisième chemin de courant de test (25), la connexion étant commutée entre le chemin de courant à la terre (26) et un second chemin de courant de test (22b).
PCT/JP2015/055264 2014-08-28 2015-02-24 Dispositif de détection de défaut à la terre et procédé de détection de défaut à la terre WO2016031269A1 (fr)

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JP2014-174538 2014-08-28
JP2014174538A JP6421498B2 (ja) 2014-08-28 2014-08-28 地絡検出装置および地絡検出方法

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3680673A1 (fr) * 2019-01-10 2020-07-15 Siemens Aktiengesellschaft Dispositif de protection destiné à la surveillance d'un réseau d'alimentation électrique, en particulier un réseau basse tension

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6665767B2 (ja) 2016-12-09 2020-03-13 オムロン株式会社 検査支援装置およびその制御方法、検査システム、並びに制御プログラム
JP6930370B2 (ja) * 2017-10-30 2021-09-01 オムロン株式会社 地絡検出装置
JP7582710B2 (ja) * 2020-09-22 2024-11-13 ファーウェイ デジタル パワー テクノロジーズ カンパニー リミテッド 太陽光発電システム、並びに太陽光発電ストリングの地絡を検出する方法及び装置
KR102541394B1 (ko) * 2020-12-30 2023-06-13 (유)중앙강재 고장예지 다면평가 테이블 기반 태양광 선로 절연 상태 위험 전조 및 스트링별 누설전류 감시 기능을 구비한 태양광 발전 장치

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03179272A (ja) * 1989-12-07 1991-08-05 Tenpaale Kogyo Kk 直流回路の地絡抵抗の表示装置
JPH0815345A (ja) * 1994-04-30 1996-01-19 Canon Inc 絶縁状態測定方法、絶縁状態判定装置及びそれを用いた分散型発電システム
JP2010153552A (ja) * 2008-12-25 2010-07-08 Fuji Electric Systems Co Ltd 太陽電池アレイの地絡試験方法
JP2010156661A (ja) * 2009-01-05 2010-07-15 Fanuc Ltd モータの絶縁劣化検出装置
JP2011066320A (ja) * 2009-09-18 2011-03-31 Tokyo Univ Of Science 太陽電池アレイの診断方法、及びパワーコンディショナ
WO2015033627A1 (fr) * 2013-09-04 2015-03-12 Ｊｘ日鉱日石エネルギー株式会社 Dispositif de mesure de résistance d'isolement, procédé de mesure de résistance d'isolement et dispositif de surveillance d'isolement

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03179272A (ja) * 1989-12-07 1991-08-05 Tenpaale Kogyo Kk 直流回路の地絡抵抗の表示装置
JPH0815345A (ja) * 1994-04-30 1996-01-19 Canon Inc 絶縁状態測定方法、絶縁状態判定装置及びそれを用いた分散型発電システム
JP2010153552A (ja) * 2008-12-25 2010-07-08 Fuji Electric Systems Co Ltd 太陽電池アレイの地絡試験方法
JP2010156661A (ja) * 2009-01-05 2010-07-15 Fanuc Ltd モータの絶縁劣化検出装置
JP2011066320A (ja) * 2009-09-18 2011-03-31 Tokyo Univ Of Science 太陽電池アレイの診断方法、及びパワーコンディショナ
WO2015033627A1 (fr) * 2013-09-04 2015-03-12 Ｊｘ日鉱日石エネルギー株式会社 Dispositif de mesure de résistance d'isolement, procédé de mesure de résistance d'isolement et dispositif de surveillance d'isolement

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3680673A1 (fr) * 2019-01-10 2020-07-15 Siemens Aktiengesellschaft Dispositif de protection destiné à la surveillance d'un réseau d'alimentation électrique, en particulier un réseau basse tension

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