A ground fault detection device and a ground fault detection method

Abstract

The present invention discloses a ground fault detection device and a detection method, comprising: a signal generating module and a detection module; the signal generating module comprises a power supply unit, a signal control unit, a micro-control unit and a discrete state control output unit, the first end of the signal control unit is electrically connected to the power supply unit, the second end of the signal control unit is electrically connected to the first end of the discrete state control output unit, the third end of the signal control unit is electrically connected to the first end of the micro-control unit, the second end of the discrete state control output unit is electrically connected to the fault device through the detection module, and the third end of the discrete state control output unit is electrically connected to the second end of the micro-control unit. The discrete state signal output by the discrete state control output unit to the fault device is measured by the detection module and the measurement feedback result is fed back to the micro-control unit, and the micro-control unit converts the low-frequency electrical signal into a discrete state signal according to the measurement feedback result and outputs it to the fault device for fault detection, thereby improving the accuracy of fault judgment.

Description

Technical Field

[0001] The present invention relates to the field of grounding fault detection of power distribution lines in power systems, and in particular to a grounding fault detection device and a detection method. Background Art

[0002] The types of distribution line faults include short circuit faults and ground faults, among which the frequency of ground faults caused by insulation abnormalities is the highest. The impedance of the insulation point to the ground varies. When a ground fault occurs in the distribution line, if the impedance of the insulation point to the ground is small, a low-frequency test signal needs to be applied to the distribution line. If the impedance of the insulation point to the ground is large, a high-voltage low-frequency signal needs to be applied to the distribution line. When a hidden ground fault occurs in the distribution line due to environmental conditions, the continuously applied high-voltage signal will make the hidden fault phenomenon disappear.

[0003] In the prior art, it is not possible to switch and output different test signals according to the size of the grounding resistance at the fault site, and since some hidden grounding faults disappear due to the continuous output of the test signal, it is impossible to accurately locate the equipment fault. Summary of the invention

[0004] The embodiments of the present invention provide a ground fault detection device and a detection method to accurately locate a faulty device and improve the accuracy of fault judgment.

[0005] In a first aspect, an embodiment of the present invention provides a ground fault detection device, comprising: a signal generating module and a detection module;

[0006] The signal generating module comprises a power supply unit, a signal control unit, a micro-control unit and a discrete state control output unit, wherein a first end of the signal control unit is electrically connected to the power supply unit, a second end of the signal control unit is electrically connected to a first end of the discrete state control output unit, a third end of the signal control unit is electrically connected to a first end of the micro-control unit, a second end of the discrete state control output unit is electrically connected to a faulty device through the detection module, and a third end of the discrete state control output unit is electrically connected to a second end of the micro-control unit;

[0007] The detection module is used to measure the discrete state signal output by the discrete state control output unit to the faulty device and feed back the measurement feedback result to the micro-control unit;

[0008] The micro-control unit is used to control the signal control unit to convert the electrical signal provided by the power supply unit into a low-frequency electrical signal according to the measurement feedback result, and also controls the discrete state control output unit to convert the low-frequency electrical signal into a discrete state signal and output it to the faulty device for fault detection.

[0009] Optionally, it also includes: an operation control module, which is communicatively connected to the signal generating module, and the signal generating module is used to send the measurement feedback result to the operation control module, and the operation control module is used to control the operation of the signal generating module according to the measurement feedback result.

[0010] Optionally, the signal generating module further includes a communication unit and a signal output interface;

[0011] The second end of the discrete state control output unit is electrically connected to the first end of the signal output interface, the second end of the signal output interface is electrically connected to the first end of the faulty device through the detection module, and the second end of the faulty device is electrically connected to the third end of the signal output interface;

[0012] The communication module is electrically connected to the third end of the micro-control unit, and is used to send the measurement feedback result received by the micro-control unit to the operation control module so that the operation control module controls the operation of the signal generating module through the communication module.

[0013] Optionally, the signal control unit includes a low-frequency constant voltage and constant current conversion circuit, a low-frequency boost circuit and an output feedback circuit;

[0014] The first end of the low-frequency constant-voltage and constant-current conversion circuit is electrically connected to the power supply unit, the second end of the low-frequency constant-voltage and constant-current conversion circuit is electrically connected to the first end of the low-frequency boost circuit, the second end of the low-frequency boost circuit is electrically connected to the first end of the discrete state control output unit and the first end of the output feedback circuit, respectively, and the second end of the output feedback circuit is electrically connected to the third end of the low-frequency constant-voltage and constant-current conversion circuit through the micro-control unit.

[0015] Optionally, the signal output by the low-frequency constant-voltage and constant-current conversion circuit includes a low-frequency constant-voltage signal and a low-frequency constant-current signal.

[0016] Optionally, the low-frequency constant current signal output by the signal control unit is 40mA, and the voltage range of the low-frequency constant voltage signal is 3000V.

[0017] Optionally, the discrete state control output unit includes an output control circuit, an output measurement circuit, a self-feedback circuit and a wireless signal feedback circuit;

[0018] The first end of the output control circuit is electrically connected to the second end of the signal control unit, the second end of the output control circuit is electrically connected to the first end of the output measurement circuit and the first end of the self-feedback circuit respectively, the second end of the self-feedback circuit is electrically connected to the third end of the output control circuit, the second end of the output measurement circuit and the wireless signal feedback circuit are electrically connected to the fourth end of the output control circuit through the micro-control unit respectively, and the third end of the output measurement circuit is electrically connected to the first end of the detection module.

[0019] In a second aspect, an embodiment of the present invention further provides a ground fault detection method, which is applied to the ground fault detection device as described in the first aspect, comprising:

[0020] The detection module measures the discrete state signal output by the discrete state control output unit to the faulty device and feeds back the measurement feedback result to the micro-control unit;

[0021] The micro-control unit controls the signal control unit to convert the electrical signal provided by the power supply unit into a low-frequency electrical signal according to the measurement feedback result, and controls the discrete state control output unit according to the measurement feedback result;

[0022] The discrete state control output unit converts the low-frequency electrical signal into a discrete state signal under the control of the signal control unit and outputs the discrete state signal to the fault device for fault detection.

[0023] Optionally, after the detection module measures the discrete state signal output by the discrete state control output unit to the faulty device and feeds back the measurement feedback result to the micro-control unit, it further includes:

[0024] The signal generating module sends the measurement feedback result to the operation control module;

[0025] The operation control module controls the operation of the signal generation module according to the received measurement feedback result.

[0026] Optionally, the signal control unit converts the electrical signal provided by the power supply unit into a low-frequency electrical signal, including:

[0027] When the measurement feedback result received by the signal control unit is less than or equal to 50KΩ, the signal control unit converts the electrical signal into a low-frequency constant current signal under the control of the micro-control unit;

[0028] When the measurement feedback result received by the signal control unit is greater than 50KΩ and less than or equal to 100KΩ, the signal control unit converts the electrical signal into a low-frequency constant voltage signal under the control of the micro-control unit.

[0029] The ground fault detection device and detection method provided by the embodiment of the present invention, the detection module measures the discrete state signal output by the discrete state control output unit to the faulty equipment and feeds back the measurement feedback result to the micro-control unit, the micro-control unit controls the signal control unit to convert the electric signal provided by the power supply unit into a low-frequency electric signal according to the measurement feedback result, and controls the discrete state control output unit to convert the low-frequency electric signal into a discrete state signal and output it to the faulty equipment for fault detection, the signal control unit realizes the conversion of the electric signal provided by the power supply unit into an adaptive and stable low-frequency electric signal, thereby ensuring the accuracy of the detection result of the detection module, and outputs the discrete state signal to the faulty equipment through the discrete state control output unit, thereby achieving the goal of not destroying the ground fault site, improving the accuracy of fault judgment, and improving the detection efficiency and accuracy of detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of the structure of a ground fault detection device provided by an embodiment of the present invention;

[0031] Figure 2 A schematic structural diagram of another ground fault detection device provided by an embodiment of the present invention;

[0032] Figure 3 A schematic diagram of the structure of another ground fault detection device provided by an embodiment of the present invention;

[0033] Figure 4 A schematic diagram of the structure of another ground fault detection device provided by an embodiment of the present invention;

[0034] Figure 5 A schematic diagram of the structure of another ground fault detection device provided by an embodiment of the present invention;

[0035] Figure 6 A schematic diagram of a flow chart of a ground fault detection method provided by an embodiment of the present invention;

[0036] Figure 7 A schematic diagram of a flow chart of another ground fault detection method provided by an embodiment of the present invention; DETAILED DESCRIPTION

[0037] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0038] Figure 1 is a schematic diagram of the structure of a ground fault detection device provided by an embodiment of the present invention, such as Figure 1As shown, the ground fault detection device includes: a signal generating module 100 and a detection module 200; the signal generating module 100 includes a power supply unit 10, a signal control unit 20, a micro control unit 30 and a discrete state control output unit 40, the first end 21 of the signal control unit 20 is electrically connected to the power supply unit 10, the second end 22 of the signal control unit 20 is electrically connected to the first end 41 of the discrete state control output unit 40, the third end 23 of the signal control unit 20 is electrically connected to the first end 31 of the micro control unit 30, and the second end 42 of the discrete state control output unit 40 is electrically connected to the first end 31 of the micro control unit 30 through the detection module 200. The faulty device 300 is electrically connected, and the third end 43 of the discrete state control output unit 40 is electrically connected to the second end 32 of the micro-control unit 30; the detection module 200 is used to measure the discrete state signal output by the discrete state control output unit 40 to the faulty device 300 and feed back the measurement feedback result to the micro-control unit 30; the micro-control unit 30 is used to control the signal control unit 20 to convert the electrical signal provided by the power supply unit 10 into a low-frequency electrical signal according to the measurement feedback result, and also control the discrete state control output unit 40 to convert the low-frequency electrical signal into a discrete state signal and output it to the faulty device 300 for fault detection.

[0039] like Figure 1 As shown, the detection module 200 is arranged between the second end 42 of the discrete state control output unit 40 and the faulty device 300. The detection module 200 measures the discrete state signal output by the discrete state control output unit 40 to the faulty device 300, and feeds back the measurement feedback result to the micro-control unit 30. The micro-control unit 30 controls the signal control unit 20 and the discrete state control output unit 40 respectively according to the measurement feedback result of the detection module 200, wherein the micro-control unit 30 controls the signal control unit 20 to convert the electrical signal provided by the power supply unit 10 into a low-frequency electrical signal, and controls the discrete state control output unit 40 to convert the low-frequency electrical signal output by the signal control unit 20 into a discrete state signal and output it to the faulty device 300 for fault detection.

[0040] It should be noted that the micro-control unit 30 controls the signal control unit 20 to convert the electrical signal provided by the power supply unit into a low-frequency electrical signal according to the measurement feedback result of the detection module 200, wherein the converted low-frequency electrical signal includes a voltage signal or a current signal.

[0041] In the ground fault detection device provided by the embodiment of the present invention, the detection module measures the discrete state signal output by the discrete state control output unit to the faulty equipment and feeds back the measurement feedback result to the micro-control unit. The micro-control unit controls the signal control unit to convert the electric signal provided by the power supply unit into a low-frequency electric signal according to the measurement feedback result, and controls the discrete state control output unit to convert the low-frequency electric signal into a discrete state signal and output it to the faulty equipment for fault detection. The signal control unit realizes the conversion of the electric signal provided by the power supply unit into an adaptive and stable low-frequency electric signal, thereby ensuring the accuracy of the detection result of the detection module. The discrete state signal is output to the faulty equipment through the discrete state control output unit, thereby achieving the goal of not destroying the ground fault site, improving the accuracy of fault judgment, and improving the detection efficiency and accuracy.

[0042] Optionally, based on the above embodiment, Figure 2 is a schematic diagram of the structure of another fault detection device provided by an embodiment of the present invention, such as Figure 2 As shown, it also includes an operation control module 400, which is communicatively connected to the signal generating module 100. The signal generating module 100 is used to send the measurement feedback result to the operation control module 400, and the operation control module 400 is used to control the operation of the signal generating module 100 according to the measurement feedback result.

[0043] like Figure 2 As shown, since the ground fault detection environment is a 10KV distribution line, there is a risk of high voltage access to the 10KV distribution system. When the signal generation module 100 is directly operated and controlled, it is easy to cause harm to the human body due to high voltage leakage. By setting the operation control module 400 to communicate with the signal generation module 100, the operation control module 400 can control the signal generation module 100. For example, the signal generation module 100 can be controlled by the operation control module 400 to start or stop the test. Further, the operation control module 400 and the signal generation module 400 can be operated without contact within a range of 30-50 meters, avoiding the threat to the personal safety of the operator caused by high voltage signals and mis-transmission of electricity, and solving the problem of equipment operation safety.

[0044] It should be noted that the communication connection between the operation control module 400 and the signal generating module 100 is performed to ensure electrical safety, and the embodiment of the present invention does not limit the wireless communication method between the operation control module 400 and the signal generating module 100.

[0045] Furthermore, the operation control module 400 can control the signal generating module 100 to start or stop working, and can also control the signal generating module 100 to perform other operations. The embodiment of the present invention does not specifically limit the specific operation control of the operation control module 400.

[0046] Optionally, based on the above embodiment, Figure 3 FIG. 1 is a schematic diagram of the structure of another fault detection device provided by an embodiment of the present invention. Figure 3 As shown, the signal generating module 100 also includes a communication unit 50 and a signal output interface 60; the second end 42 of the discrete state control output unit 40 is electrically connected to the first end 61 of the signal output interface 60, the second end 62 of the signal output interface 60 is electrically connected to the first end 301 of the fault device 300 through the detection module 200, and the second end 302 of the fault device 300 is electrically connected to the third end 63 of the signal output interface 60; the communication unit 50 is electrically connected to the third end 33 of the micro-control unit 30, and the communication unit 50 is used to send the measurement feedback result received by the micro-control unit 30 to the operation control module 400 so that the operation control module 400 controls the operation of the signal generating module 100 through the communication unit 50.

[0047] like Figure 3 As shown, the signal generating module 100 also includes a signal output interface 60, the second end 42 of the discrete state control output unit 40 is electrically connected to the first end 61 of the signal output interface 60, the second end 62 of the signal output interface 60 is electrically connected to the first end 301 of the fault device 300 through the detection module 200, the second end 302 of the fault device 300 is electrically connected to the third end 63 of the signal output interface 60, and the electrical connection between the fault device 300 and the signal generating module 100 is realized through the signal output interface 60, and since the first end 301 and the second end 302 of the fault device 300 are connected between the second end 62 and the third end 63 of the signal output interface 60, the electrical connection between the fault device 300 and the signal generating module 100 can be directly realized through the wiring pins.

[0048] Furthermore, by setting the communication unit 50 to be electrically connected to the third end 33 of the micro-control unit 30, the communication unit 50 sends the measurement feedback result received by the micro-control unit 30 to the operation control module 400 so that the operation control module 400 controls the operation of the signal generating module 100 through the communication unit 50, thereby realizing communication between the operation control module 400 and the signal generating module 100.

[0049] Optional, such as Figure 4As shown, the signal control unit 20 includes a low-frequency constant voltage and constant current conversion circuit 210, a low-frequency boost circuit 220 and an output feedback circuit 230. The first end 211 of the low-frequency constant voltage and constant current conversion circuit 210 is electrically connected to the power supply unit 10, the second end 212 of the low-frequency constant voltage and constant current conversion circuit 210 is electrically connected to the first end 221 of the low-frequency boost circuit 220, the second end 222 of the low-frequency boost circuit 220 is electrically connected to the first end 41 of the discrete state control output unit 40 and the first end 231 of the output feedback circuit 230, respectively, and the second end 232 of the output feedback circuit 230 is electrically connected to the third end 213 of the low-frequency constant voltage and constant current conversion circuit 210 through the micro-control unit 30.

[0050] like Figure 4 As shown, the first end 211 of the low-frequency constant voltage and constant current conversion circuit 210 of the signal control unit 20 is electrically connected to the power supply unit 10. After the signal control unit 20 receives the measurement feedback result, the low-frequency constant voltage and constant current conversion circuit 210 is controlled to output a low-frequency constant voltage signal or a low-frequency constant current signal according to the measurement feedback result. For example, when the grounding resistance of the faulty device line in the measurement feedback result received by the signal control unit 20 is less than or equal to 50KΩ, the low-frequency constant voltage and constant current conversion circuit 210 is controlled to output a low-frequency constant current signal. When the grounding resistance of the faulty device line in the measurement feedback result received by the signal control unit 20 is greater than 50KΩ and less than or equal to 100KΩ, the low-frequency constant voltage and constant current conversion circuit 210 is controlled to output a low-frequency constant voltage signal.

[0051] The low-frequency constant voltage signal or low-frequency constant current signal output by the low-frequency constant voltage and constant current conversion circuit 210 is converted into a high-voltage signal after passing through the low-frequency boost circuit 220, and the signal is fed back to the micro-control unit 30 through the output feedback circuit 230. The micro-control unit 30 controls the low-frequency constant voltage and constant current conversion circuit 210 to perform output switching of the low-frequency constant voltage signal or the low-frequency constant current signal according to the resistance value calculated by the output feedback circuit 230. The low-frequency constant current signal is output as a constant current 40mA electrical signal after passing through the low-frequency boost circuit 220, and the low-frequency constant voltage signal is output as a constant voltage 3kV electrical signal after passing through the low-frequency boost circuit 220. The low-frequency constant current signal or the low-frequency constant voltage and low-voltage signal is converted into a high-voltage and low-frequency constant voltage or constant current signal through the low-frequency boost circuit 220, providing an obvious characteristic signal, thereby ensuring that the grounding fault point is quickly and accurately located.

[0052] It should be noted that the first end 211 of the low-frequency constant-voltage constant-current conversion circuit 210 is the first end 21 of the signal control unit 20 , and the second end 222 of the low-frequency boost circuit 220 is the second end 22 of the signal control unit 20 .

[0053] Optionally, the signal output by the low-frequency constant-voltage constant-current conversion circuit 210 includes a low-frequency constant-voltage signal and a low-frequency constant-current signal.

[0054] The low-frequency constant voltage and constant current conversion circuit 210 is used to convert the electrical signal output by the power supply unit 10 into a low-frequency constant voltage signal or a low-frequency constant current signal. Since the low-frequency constant current signal has obvious characteristics when the grounding resistance of the faulty device is less than or equal to 50KΩ, when the grounding resistance of the faulty device 300 detected by the detection module 200 is less than or equal to 50KΩ, the measurement feedback result is fed back to the micro-control unit 30, and the micro-control unit 30 controls the low-frequency constant voltage and constant current conversion circuit 210 according to the measurement feedback result to convert the electrical signal of the power supply unit 10 into a low-frequency constant current signal output, thereby accurately locating the fault point of the faulty device 300. When the grounding resistance of the faulty device 300 is greater than 50KΩ and less than or equal to 100KΩ, the low-frequency constant voltage signal has obvious characteristics. Therefore, when the grounding resistance of the faulty device 300 detected by the detection module 200 is greater than 50KΩ and less than or equal to 100KΩ, the measurement feedback result is fed back to the micro-control unit 30. The micro-control unit 30 controls the low-frequency constant voltage and constant current conversion circuit 210 to automatically switch the electrical signal of the power supply unit 10 to the low-frequency constant voltage output according to the measurement feedback result, providing an obvious characteristic signal, ensuring that the detection module 200 can conveniently and directly detect the characteristic signal, and the applicability and accuracy of ground fault troubleshooting are greatly improved.

[0055] Optionally, the current range of the low-frequency constant current signal is 0-40mA, and the voltage range of the low-frequency constant voltage signal is 0-3000V.

[0056] Furthermore, since the signal output by the signal generating module 20 in the grounding fault detection device may be weak, resulting in inaccurate measurement results of the detection module 200, a low-frequency boost circuit 220 is set in the signal control unit 20. When the low-frequency constant voltage and constant current conversion circuit 210 outputs a low-frequency constant voltage signal or a low-frequency constant current signal according to the measurement feedback result, the low-frequency constant voltage signal and the low-frequency constant current signal pass through the low-frequency boost circuit 220, and the low-frequency constant current signal is converted into a 40mA constant current electrical signal, and the low-frequency constant voltage signal is converted into a 3000V constant voltage electrical signal, thereby ensuring that the signal control unit 20 provides an obvious characteristic signal, which provides a guarantee for the subsequent detection module 200 to quickly and accurately locate the grounding fault point.

[0057] It should be noted that the embodiment of the present invention does not specifically limit the current range of the low-frequency constant current signal and the voltage of the low-frequency constant voltage signal. When the ground detection device is different from the detection equipment outside, specific limitations can be made according to the circuit structure.

[0058] Optionally, based on the above embodiment, Figure 5 FIG. 1 is a schematic diagram of the structure of another fault detection device provided by an embodiment of the present invention. Figure 5As shown, the discrete state control output unit 40 includes an output control circuit 410, an output measurement circuit 420, a self-feedback circuit 430 and a wireless signal feedback circuit 440; the first end 411 of the output control circuit 410 is electrically connected to the second end 21 of the signal control unit 20, the second end 412 of the output control circuit 410 is electrically connected to the first end 421 of the output measurement circuit 420 and the first end 431 of the self-feedback circuit 430 respectively, the second end 432 of the self-feedback circuit 430 is electrically connected to the third end 413 of the output control circuit 410, the second end 422 of the output measurement circuit 420 and the wireless signal feedback circuit 440 are electrically connected to the fourth end 414 of the output control circuit 410 through the micro-control unit 30 respectively, and the third end 423 of the output measurement circuit 420 is electrically connected to the detection module 200.

[0059] The discrete state control output unit 40 receives the constant current electrical signal or constant voltage electrical signal output by the signal control unit 20, and converts the received constant current electrical signal or constant voltage electrical signal into a discrete state signal output through the output control circuit 410 and the self-feedback circuit 430. The output pulse width of the discrete state signal is controlled by the measurement value of the output measurement circuit 420 and the signal of the wireless signal feedback circuit 440 to ensure that the output signal is a discontinuous discrete signal.

[0060] It should be noted that the first terminal 411 of the output control circuit 410 is the first terminal 41 of the discrete state control output unit 40 , and the third terminal 423 of the output measurement circuit 420 is the second terminal 423 of the discrete state control output unit 40 .

[0061] Based on the above embodiments, Figure 6 A ground fault detection method provided by an embodiment of the present invention is as follows: Figure 6 As shown, the ground fault detection method includes:

[0062] S110, the detection module measures the discrete state signal output by the discrete state control output unit to the faulty device and feeds back the measurement feedback result to the micro-control unit.

[0063] S120, the micro-control unit controls the signal control unit to convert the electrical signal provided by the power supply unit into a low-frequency electrical signal according to the measurement feedback result, and controls the discrete state control output unit according to the measurement feedback result.

[0064] The signal control unit converts the electrical signal provided by the power supply unit into a low-frequency electrical signal, including:

[0065] When the measurement feedback result received by the signal control unit is less than or equal to 50KΩ, the signal control unit converts the electrical signal into a low-frequency current signal under the control of the micro-control unit;

[0066] When the measurement feedback result received by the signal control unit is greater than 50KΩ and less than or equal to 100KΩ, the signal control unit converts the electrical signal into a low-frequency voltage signal under the control of the micro-control unit.

[0067] S130. The discrete state control output unit, under the control of the signal control unit, converts the low-frequency electrical signal into a discrete state signal and outputs it to the faulty device for fault detection.

[0068] In the ground fault detection method provided by the embodiment of the present invention, the detection module measures the discrete state signal output by the discrete state control output unit to the faulty device and feeds back the measurement feedback result to the micro-control unit. The micro-control unit controls the signal control unit to convert the electrical signal provided by the power supply unit into a low-frequency electrical signal according to the measurement feedback result, and controls the discrete state control output unit to convert the low-frequency electrical signal into a discrete state signal and output it to the faulty device for fault detection. The signal control unit realizes the conversion of the electrical signal provided by the power supply unit into an adaptive and stable low-frequency electrical signal, thereby ensuring the accuracy of the detection result of the detection module. The discrete state signal is output to the faulty device through the discrete state control output unit, thereby achieving the goal of not destroying the ground fault site, improving the accuracy of fault judgment, and improving the detection efficiency and accuracy of detection.

[0069] Based on the above embodiments, Figure 7 Another ground fault detection method provided by an embodiment of the present invention is as follows: Figure 7 As shown, the ground fault detection method includes:

[0070] S210: The signal generating module sends the measurement feedback result to the operation control module.

[0071] S220: The operation control module controls the operation of the signal generation module according to the received measurement feedback result.

[0072] The ground fault detection method provided in the embodiment of the present invention controls the operation module to operate the signal generating module according to the measurement feedback result received by the signal generating module, thereby avoiding the threat to the personal safety of the operator caused by high-voltage signals and mis-power transmission, and solving the operational safety problem of the equipment.

[0073] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A ground fault detection device, characterized in that: include: Signal generation module and detection module; The signal generating module comprises a power supply unit, a signal control unit, a micro-control unit and a discrete state control output unit, wherein a first end of the signal control unit is electrically connected to the power supply unit, a second end of the signal control unit is electrically connected to a first end of the discrete state control output unit, a third end of the signal control unit is electrically connected to a first end of the micro-control unit, a second end of the discrete state control output unit is electrically connected to a faulty device through the detection module, and a third end of the discrete state control output unit is electrically connected to a second end of the micro-control unit; The detection module is used to measure the discrete state signal output by the discrete state control output unit to the faulty device and feed back the measurement feedback result to the micro-control unit; The micro-control unit is used to control the signal control unit to convert the electrical signal provided by the power supply unit into a low-frequency electrical signal according to the measurement feedback result, and also control the discrete state control output unit to convert the low-frequency electrical signal into a discrete state signal and output it to the faulty device for fault detection; It also includes: an operation control module, the operation control module is communicatively connected with the signal generating module, the signal generating module is used to send the measurement feedback result to the operation control module, and the operation control module is used to control the operation of the signal generating module according to the measurement feedback result; The signal control unit includes a low-frequency constant voltage and constant current conversion circuit, a low-frequency boost circuit and an output feedback circuit; The first end of the low-frequency constant-voltage and constant-current conversion circuit is electrically connected to the power supply unit, the second end of the low-frequency constant-voltage and constant-current conversion circuit is electrically connected to the first end of the low-frequency boost circuit, the second end of the low-frequency boost circuit is electrically connected to the first end of the discrete state control output unit and the first end of the output feedback circuit, respectively, and the second end of the output feedback circuit is electrically connected to the third end of the low-frequency constant-voltage and constant-current conversion circuit through the micro-control unit.

2. The ground fault detection device according to claim 1, characterized in that: The signal generating module also includes a communication unit and a signal output interface; The second end of the discrete state control output unit is electrically connected to the first end of the signal output interface, the second end of the signal output interface is electrically connected to the first end of the faulty device through the detection module, and the second end of the faulty device is electrically connected to the third end of the signal output interface; The communication unit is electrically connected to the third end of the micro-control unit, and is used to send the measurement feedback result received by the micro-control unit to the operation control module so that the operation control module controls the operation of the signal generating module through the communication unit.

3. The ground fault detection device according to claim 1, characterized in that: The signal output by the low-frequency constant-voltage and constant-current conversion circuit includes a low-frequency constant-voltage signal and a low-frequency constant-current signal.

4. The ground fault detection device according to claim 3, characterized in that: The current of the low-frequency constant current signal output by the signal control unit is 40mA, and the voltage of the low-frequency constant voltage signal is 3000V.

5. The ground fault detection device according to claim 1, characterized in that: The discrete state control output unit includes an output control circuit, an output measurement circuit, a self-feedback circuit and a wireless signal feedback circuit; The first end of the output control circuit is electrically connected to the second end of the signal control unit, the second end of the output control circuit is electrically connected to the first end of the output measurement circuit and the first end of the self-feedback circuit respectively, the second end of the self-feedback circuit is electrically connected to the third end of the output control circuit, the second end of the output measurement circuit and the wireless signal feedback circuit are electrically connected to the fourth end of the output control circuit through the micro-control unit respectively, and the third end of the output measurement circuit is electrically connected to the detection module.

6. A ground fault detection method, characterized in that: Applicable to the ground fault detection device according to any one of claims 1 to 5, comprising: The detection module measures the discrete state signal output by the discrete state control output unit to the faulty device and feeds back the measurement feedback result to the micro-control unit; The micro-control unit controls the signal control unit to convert the electrical signal provided by the power supply unit into a low-frequency electrical signal according to the measurement feedback result, and controls the discrete state control output unit according to the measurement feedback result; The discrete state control output unit converts the low-frequency electrical signal into a discrete state signal under the control of the signal control unit and outputs the discrete state signal to the fault device for fault detection.

7. The ground fault detection method according to claim 6, characterized in that: After the detection module measures the discrete state signal output by the discrete state control output unit to the faulty device and feeds back the measurement feedback result to the micro-control unit, it also includes: The signal generating module sends the measurement feedback result to the operation control module; The operation control module controls the operation of the signal generation module according to the received measurement feedback result.

8. The ground fault detection method according to claim 6, characterized in that: The signal control unit converts the electrical signal provided by the power supply unit into a low-frequency electrical signal, including: When the measurement feedback result received by the signal control unit is less than or equal to 50KΩ, the signal control unit converts the electrical signal into a low-frequency constant current signal under the control of the micro-control unit; When the measurement feedback result received by the signal control unit is greater than 50KΩ and less than or equal to 100KΩ, the signal control unit converts the electrical signal into a low-frequency constant voltage signal under the control of the micro-control unit.

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