Method and device for detecting high-resistance grounding fault of power distribution network

Abstract

The invention discloses a method and a device for detecting a high-resistance grounding fault of a power distribution network. The method comprises the following steps of: acquiring residual current measured by an annular current transformer mounted in a transformer substation, residual voltage along a feeder line and a V2 / V1 ratio at the downstream of a high-resistance grounding fault test point; and detecting the high-resistance grounding fault of the power distribution network according to the residual current, the residual voltage, the V2 / V1 ratio and a preset high-resistance grounding fault detection rule. According to the invention, the efficiency of high-resistance grounding fault detection can be improved.

Description

Technical Field

[0001] The present invention relates to a high-resistance grounding fault, and in particular to a method and a device for detecting a high-resistance grounding fault in a distribution network. Background Art

[0002] A high impedance ground fault (HIF) refers to a ground fault in a power system caused by a conductor contacting a high impedance medium (such as dry soil, trees, concrete, etc.) due to equipment failure or conductor breakage. This type of fault is different from a low resistance ground fault (such as a conductor directly contacting a metal object or moist soil) because in a high resistance ground fault, the fault current is usually small and may not be detected in time by traditional protection devices (such as overcurrent protection). At present, when a high resistance ground fault occurs, it takes a long time, manpower and material resources to manually patrol each branch of the faulty line in turn to determine the section where the fault grounding point is located. The existing technology lacks a more efficient solution for determining high resistance ground faults. Summary of the invention

[0003] In order to solve at least one technical problem in the above-mentioned background technology, the present invention proposes a method and device for detecting high-resistance grounding faults in a distribution network.

[0004] In order to achieve the above object, according to one aspect of the present invention, a method for detecting a high-resistance grounding fault in a distribution network is provided, the method comprising:

[0005] Obtain the residual current measured by the toroidal current transformer installed in the substation, the residual voltage along the feeder, and the V2 / V1 ratio downstream of the high-resistance earth fault test point;

[0006] The power distribution network high-resistance grounding fault detection is performed according to the residual current, the residual voltage, the V2 / V1 ratio and a preset high-resistance grounding fault detection rule.

[0007] Optionally, the high-resistance grounding fault detection rule includes: when the residual current increases, the residual voltage decreases, and the V2 / V1 ratio increases, it is determined that a high-resistance grounding fault occurs.

[0008] Optionally, the distribution network high-resistance grounding fault detection method further includes:

[0009] Establishing a laboratory test system, wherein the laboratory test system comprises: a transformer, a busbar, a grounding reactor, and a plurality of distribution feeders, wherein the busbar is connected to the reactor;

[0010] Based on the laboratory test system, a high-resistance grounding fault is simulated to obtain simulated fault data, wherein the simulated fault data includes: the residual current, the residual voltage and the V2 / V1 ratio;

[0011] The high-resistance grounding fault detection rule is determined according to the simulated fault data.

[0012] Optionally, the distribution network high-resistance grounding fault detection method further includes:

[0013] Performing digital simulation on the laboratory test system to obtain a laboratory simulation model;

[0014] By simulating a high-resistance grounding fault in the laboratory simulation model, the high-resistance grounding fault detection rule is verified and optimized.

[0015] Optionally, the distribution network high-resistance grounding fault detection method further includes:

[0016] By performing a high-resistance grounding fault simulation in an actual feeder, actual fault simulation data is obtained, wherein the actual fault simulation data includes: the residual current, the residual voltage, and the V2 / V1 ratio;

[0017] The high-resistance grounding fault detection rule is determined according to the actual fault simulation data.

[0018] Optionally, the distribution network high-resistance grounding fault detection method further includes:

[0019] Perform digital simulation on the actual feeder to obtain a feeder simulation model;

[0020] By simulating a high-resistance grounding fault in the feeder simulation model, the high-resistance grounding fault detection rule is verified and optimized.

[0021] In order to achieve the above object, according to another aspect of the present invention, a device for detecting high-resistance grounding faults in a distribution network is provided, the device comprising:

[0022] A data acquisition unit for acquiring the residual current measured by the toroidal current transformer installed in the substation, the residual voltage along the feeder, and the V2 / V1 ratio downstream of the high-resistance earth fault test point;

[0023] The high-resistance grounding fault detection unit is used to perform high-resistance grounding fault detection on the distribution network according to the residual current, the residual voltage, the V2 / V1 ratio and a preset high-resistance grounding fault detection rule.

[0024] Optionally, the high-resistance grounding fault detection rule includes: when the residual current increases, the residual voltage decreases, and the V2 / V1 ratio increases, it is determined that a high-resistance grounding fault occurs.

[0025] Optionally, the distribution network high-resistance grounding fault detection device further includes:

[0026] A laboratory test system establishment unit, used to establish a laboratory test system, wherein the laboratory test system comprises: a transformer, a busbar, a grounding reactor and a plurality of distribution feeders, wherein the busbar is connected to the reactor;

[0027] A laboratory fault simulation unit, used for simulating a high-resistance grounding fault based on the laboratory test system to obtain simulated fault data, wherein the simulated fault data includes: the residual current, the residual voltage and the V2 / V1 ratio;

[0028] The first high-resistance grounding fault detection rule determining unit is configured to determine the high-resistance grounding fault detection rule according to the simulated fault data.

[0029] Optionally, the distribution network high-resistance grounding fault detection device further includes:

[0030] A laboratory simulation model building unit, used for digitally simulating the laboratory test system to obtain a laboratory simulation model;

[0031] The first rule verification and optimization unit is used to verify and optimize the high-resistance grounding fault detection rule by simulating the high-resistance grounding fault in the laboratory simulation model.

[0032] Optionally, the distribution network high-resistance grounding fault detection device further includes:

[0033] An actual feeder fault simulation unit, used for obtaining actual fault simulation data by simulating a high-resistance grounding fault in an actual feeder, wherein the actual fault simulation data includes: the residual current, the residual voltage and the V2 / V1 ratio;

[0034] The second high-resistance grounding fault detection rule determination unit is configured to determine the high-resistance grounding fault detection rule according to the actual fault simulation data.

[0035] Optionally, the distribution network high-resistance grounding fault detection device further includes:

[0036] A feeder simulation model building unit is used to digitally simulate the actual feeder to obtain a feeder simulation model;

[0037] The second rule verification and optimization unit is used to verify and optimize the high-resistance grounding fault detection rule by simulating the high-resistance grounding fault in the feeder simulation model.

[0038] In order to achieve the above-mentioned purpose, according to another aspect of the present invention, a computer device is further provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned method for detecting high-resistance grounding faults in a distribution network when executing the computer program.

[0039] In order to achieve the above object, according to another aspect of the present invention, a computer-readable storage medium is provided, on which a computer program / instruction is stored. When the computer program / instruction is executed by a processor, the steps of the above-mentioned distribution network high-resistance grounding fault detection method are implemented.

[0040] In order to achieve the above object, according to another aspect of the present invention, a computer program product is further provided, including a computer program / instruction, which implements the steps of the above distribution network high-resistance grounding fault detection method when executed by a processor.

[0041] The beneficial effects of the present invention are:

[0042] The embodiment of the present invention obtains the residual current measured by the toroidal current transformer installed in the substation, the residual voltage along the feeder, and the V2 / V1 ratio downstream of the high-resistance grounding fault test point, and then performs high-resistance grounding fault detection in the distribution network according to the residual current, the residual voltage, the V2 / V1 ratio, and a preset high-resistance grounding fault detection rule, thereby improving the efficiency of high-resistance grounding fault detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0044] Figure 1 is a flow chart of a method for detecting a high-resistance grounding fault in a distribution network according to an embodiment of the present invention;

[0045] Figure 2 is a first flow chart for determining a high-resistance grounding fault detection rule according to an embodiment of the present invention;

[0046] Figure 3 This is a first flow chart of verifying and optimizing detection rules according to an embodiment of the present invention;

[0047] Figure 4 is a second flow chart for determining a high-resistance grounding fault detection rule according to an embodiment of the present invention;

[0048] Figure 5 is a second flow chart of verifying and optimizing detection rules according to an embodiment of the present invention;

[0049] Figure 6 It is a structural block diagram of a device for detecting high-resistance grounding faults in a distribution network according to an embodiment of the present invention;

[0050] Figure 7 It is a schematic diagram of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0051] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0052] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0053] It should be noted that the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or apparatus.

[0054] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0055] Figure 1 Flow chart of the method for detecting high-resistance grounding fault in distribution network according to an embodiment of the present invention. Figure 1 As shown, in one embodiment of the present invention, the method for detecting a high-resistance grounding fault in a distribution network of the present invention includes step S101 and step S102.

[0056] Step S101 , obtaining the residual current measured by the toroidal current transformer installed in the substation, the residual voltage along the feeder, and the V2 / V1 ratio downstream of the high-resistance ground fault test point.

[0057] Residual current (also called zero-sequence current) refers to the vector sum of three-phase currents, usually represented by 3I0, which reflects the unbalanced current situation in the power system. In substations, ring current transformers (CTs) are used to measure the zero-sequence component of three-phase currents. When a high-resistance ground fault occurs, the unbalanced current in the system will cause an increase in zero-sequence current, and the ring CT can monitor this change in real time. The increase in residual current is usually an important indication of a high-resistance ground fault. By monitoring this parameter, the fault can be detected in time and appropriate measures can be taken.

[0058] Residual voltage refers to the voltage measured in the grounding system, usually represented by V0. In the case of a ground fault, the residual voltage reflects the change in potential relative to the ground. Voltage sensors are installed along the distribution feeders to monitor the changes in residual voltage in real time. When a high-resistance ground fault occurs, the fluctuation and change characteristics of the residual voltage can help identify the presence of the fault. A significant decrease or fluctuation in the residual voltage may indicate the occurrence of a ground fault. By monitoring V0, the severity and type of the fault can be determined, providing a basis for fault location.

[0059] The V2 / V1 ratio refers to the ratio of the negative sequence voltage (V2) to the positive sequence voltage (V1) in symmetrical component analysis. It is used to describe the voltage imbalance state of the system. Downstream of the high-resistance ground fault test point, voltage sensors are used to measure the values ​​of V2 and V1 and calculate their ratio. Under normal circumstances, the V2 / V1 ratio should be small, but this ratio will increase significantly when a ground fault occurs. An increase in the V2 / V1 ratio usually indicates an imbalance in the system and may indicate the presence of a high-resistance ground fault. By monitoring this ratio, it can assist in determining the location and type of the fault.

[0060] These three parameters (residual current, residual voltage and V2 / V1 ratio) complement each other and together constitute important indicators for high-resistance ground fault detection. By real-time monitoring of these parameters, the detection accuracy of high-resistance ground faults can be improved to ensure the safe operation of the power system.

[0061] Step S102 : performing distribution network high-resistance grounding fault detection according to the residual current, the residual voltage, the V2 / V1 ratio and a preset high-resistance grounding fault detection rule.

[0062] The present invention can quickly detect high-resistance grounding faults by real-time monitoring of the above three parameters and combining with preset high-resistance grounding fault detection rules. After real feeder testing, the accuracy of the distribution network high-resistance grounding fault detection method of the present invention can reach more than 80%, which shows that the distribution network high-resistance grounding fault detection method of the present invention has good accuracy.

[0063] In one embodiment of the present invention, the high-resistance grounding fault detection rule includes: when the residual current increases, the residual voltage decreases, and the V2 / V1 ratio increases, it is determined that a high-resistance grounding fault occurs.

[0064] In one embodiment of the present invention, the high-resistance grounding fault detection rule is: when the residual current exceeds a first threshold, the residual voltage is lower than a second threshold and the V2 / V1 ratio exceeds a third threshold, a high-resistance grounding fault is determined to have occurred; otherwise, a high-resistance grounding fault is determined not to have occurred.

[0065] Figure 2 is a first flow chart of determining a high-resistance ground fault detection rule according to an embodiment of the present invention, such as Figure 2 As shown, in one embodiment of the present invention, the process of determining a high-resistance grounding fault detection rule of the present invention includes steps S201 to S203.

[0066] Step S201, establishing a laboratory test system, wherein the laboratory test system includes: a transformer, a busbar, a grounding reactor, and a plurality of distribution feeders, wherein the busbar is connected to the reactor.

[0067] In a specific embodiment of the present invention, the laboratory test system consists of a 35-10kV transformer star-grounded-delta-grounded substation, a 10kV busbar and three rural distribution feeders. The 10kV Delta busbar is connected to a Zig-Zag grounding reactor.

[0068] Step S202, based on the laboratory test system, simulate a high-resistance grounding fault to obtain simulated fault data, wherein the simulated fault data includes: the residual current, the residual voltage and the V2 / V1 ratio.

[0069] In one embodiment of the present invention, the present invention simulates two faults: a source-side high-resistance grounding fault and a load-side high-resistance grounding fault.

[0070] In one embodiment of the present invention, when simulating a high-resistance grounding fault, the present invention further sets the grounding resistance to be between 20 kΩ and 80 kΩ to simulate different high-resistance grounding conditions.

[0071] After the simulated fault occurs, the present invention uses a data acquisition system to monitor and record the following data in real time: residual current (3I0): measured and recorded by a toroidal current transformer; residual voltage (V0): measured and recorded by a voltage sensor; V2 / V1 ratio: calculate and record the positive sequence voltage (V1) and the negative sequence voltage (V2), and then calculate their ratio. The present invention also performs data recording, using a digital oscilloscope to record the waveform data of the above parameters, ensuring that the changes before and after the fault can be captured, and storing the data for subsequent analysis and processing.

[0072] Step S203: determining the high-resistance grounding fault detection rule according to the simulated fault data.

[0073] In one embodiment of the present invention, the present invention performs statistical analysis on the collected simulated fault data, including the changes in residual current, residual voltage and V2 / V1 ratio, and then compares the changes in each parameter before and after the fault occurs to identify key features.

[0074] When determining the high-resistance grounding fault detection rule, the present invention sets a threshold value for the residual current, such as when 3I0 exceeds 1A, it is determined to be a possible high-resistance grounding fault; sets a threshold value for the residual voltage, such as when V0 drops by more than 20%, it is determined to be a high-resistance grounding fault; sets a threshold value for the V2 / V1 ratio, such as when the V2 / V1 ratio exceeds 0.5, it is determined to be unbalanced and a high-resistance grounding fault.

[0075] Figure 3 is a first flow chart of verifying and optimizing the detection rules in an embodiment of the present invention, such as Figure 3 As shown, in one embodiment of the present invention, the process of verifying and optimizing the detection rules of the present invention includes step S301 and step S302.

[0076] Step S301, digitally simulate the laboratory test system to obtain a laboratory simulation model.

[0077] In one embodiment of the present invention, the present invention can use ATP (Alternative Transient Program) or other power system simulation software to establish a digital simulation model of the laboratory test system. When establishing the simulation model, a corresponding model is constructed for each component (such as a transformer, grounding reactor, and feeder) to ensure that its behavior in the power system can be accurately reflected. In addition, it is also necessary to input the electrical parameters of the transformer, busbar, reactor, and feeder according to the actual configuration of the laboratory test system, including the rated voltage, rated power, and connection method.

[0078] Step S302 , verifying and optimizing the high-resistance grounding fault detection rule by simulating a high-resistance grounding fault in the laboratory simulation model.

[0079] When performing fault simulation, different types of high-resistance grounding faults are set in the simulation model, including source-side and load-side faults. Different grounding resistance values ​​(such as 20kΩ, 40kΩ, 80kΩ) are set to simulate various fault conditions. The dynamic response of the monitoring system when a high-resistance grounding fault occurs is monitored, and changes in key parameters, residual current (3I0), residual voltage (V0), and V2 / V1 ratio are recorded.

[0080] The present invention compares the residual current, residual voltage and V2 / V1 ratio data collected during the simulation process with the previously formulated detection rules to analyze whether they meet the rule settings. The present invention checks the accuracy of each detection rule, for example, whether it is accurately determined as a high-resistance grounding fault when 3I0 exceeds the set threshold. In addition, the present invention evaluates the sensitivity and specificity of the detection rules to determine the effectiveness of the rules under different fault conditions.

[0081] When optimizing the detection rules, the present invention adjusts the threshold of the detection rules according to the simulation results to improve the accuracy of fault detection. For example, if a threshold causes a false alarm under certain conditions, consider resetting it. And combine multiple parameters (such as 3I0, V0 and V2 / V1) for comprehensive analysis, and it may be necessary to formulate new comprehensive rules to enhance the detection capability.

[0082] The present invention conducts feedback loops through continuous simulation and data analysis, and repeatedly verifies the optimized rules to ensure their consistency and effectiveness in laboratory simulation models and actual tests.

[0083] Figure 4 is a second flow chart of determining a high-resistance ground fault detection rule according to an embodiment of the present invention, such as Figure 4 As shown, in one embodiment of the present invention, the process of determining a high-resistance grounding fault detection rule of the present invention includes step S401 and step S402.

[0084] Step S401 , obtaining actual fault simulation data by simulating a high-resistance grounding fault in an actual feeder, wherein the actual fault simulation data includes: the residual current, the residual voltage and the V2 / V1 ratio.

[0085] In a specific embodiment of the present invention, for the fault simulation of a real feeder, a digital oscilloscope recorder and voltage and current sensors need to be installed along the length of the feeder. The measurement points are named MS0, MS1, MS2, MS3 and MS4. A ring CT is installed at MS0 to provide residual current. The feeder has 5 automatic reclosers named ADE (at the substation), VCG, CSC, PRB, which are usually closed, and PRA is usually open. During the field test, high-resistance ground faults were simulated only at the HIF3 and HIF4 test points. The HIF3 point is located 9.3 kilometers from the substation, and HIF 4 is approximately 12.5 kilometers. Cable fault tests to ground were conducted for the HIF3 and HIF4 points, simulating load-side HIF and source-side HIF. Field tests at the HIF3 point: Tests were conducted on asphalt, concrete and grass surfaces. At the HIF4 point, tests were conducted only on clay soil surfaces.

[0086] In one embodiment of the present invention, when simulating an actual feeder fault, the present invention first selects an actual distribution feeder suitable for high-resistance ground fault simulation to ensure that the feeder is representative and can reflect different load and environmental conditions. The present invention installs necessary measurement equipment at the test site, including a toroidal current transformer (CT), a voltage sensor, and a data recorder. And the necessary switching devices are set so that a high-resistance ground fault (source-side high-resistance ground fault and load-side high-resistance ground fault) can be created when necessary.

[0087] When simulating a high-resistance ground fault, a high-resistance ground fault on the source side or the load side is simulated by opening a specific switch (such as S1 or S2). The ground resistance can be set between 20kΩ and 80kΩ to simulate different fault conditions. During the fault simulation, the following parameters are monitored and recorded in real time: residual current (3I0): data obtained using a ring CT; residual voltage (V0): measured by a voltage sensor; V2 / V1 ratio: the ratio of the positive sequence voltage (V1) to the negative sequence voltage (V2) is calculated and recorded in real time.

[0088] Step S402: determining the high-resistance grounding fault detection rule according to the actual fault simulation data.

[0089] In the present invention, this step performs data analysis based on the actual fault simulation data to identify the characteristics of the high-resistance grounding fault, and then summarizes the high-resistance grounding fault detection rules.

[0090] In one embodiment of the present invention, the present invention performs comprehensive data analysis based on the simulated fault data obtained in step S202 and the actual fault simulation data obtained in step S401 to identify the characteristics of the high-resistance grounding fault and then summarize the high-resistance grounding fault detection rules.

[0091] Figure 5 is a second flow chart of verifying and optimizing the detection rules according to an embodiment of the present invention, such as Figure 5 As shown, in one embodiment of the present invention, the process of verifying and optimizing the detection rules of the present invention includes step S501 and step S502.

[0092] Step S501, digitally simulate the actual feeder to obtain a feeder simulation model.

[0093] In order to perform digital simulation, the present invention converts the geographical reference data of the feeder into the ATP model. During the digital simulation, the present invention inputs the electrical parameters of the transformer, busbar, grounding reactor, feeder and load according to the actual feeder configuration, including rated voltage, rated power, line length, impedance, etc.

[0094] Step S502: verifying and optimizing the high-resistance grounding fault detection rule by simulating a high-resistance grounding fault in the feeder simulation model.

[0095] The present invention compares the data collected during the simulation process with the previously formulated detection rules to verify the accuracy and applicability of the rules. The present invention adjusts the threshold of the detection rule based on the results of the simulation analysis to improve its accuracy. For example, if a threshold fails to effectively detect a fault under certain conditions, it can be considered to be reset.

[0096] In one embodiment of the present invention, the present invention can comprehensively verify and optimize the high-resistance grounding fault detection rules by simulating high-resistance grounding faults in the laboratory simulation model and the feeder simulation model to improve the effectiveness of the rules.

[0097] It can be seen from the above embodiments that the method for detecting high-resistance grounding faults in a distribution network of the present invention achieves at least the following beneficial effects:

[0098] 1. High-precision fault detection is achieved. By establishing scientific detection rules, the present invention can accurately identify and classify high-resistance grounding faults, improve the sensitivity and accuracy of fault detection, and effectively reduce the possibility of false alarms and missed alarms.

[0099] 2. Improved system reliability: The present invention tests and digitally simulates actual feeders to ensure that the detection rules are effective under a variety of practical and theoretical conditions, thereby improving the overall reliability and safety of the power system.

[0100] 3. The data analysis obtained through simulation and laboratory testing in this invention provides a scientific basis for fault detection and maintenance decision-making, which helps to optimize operation and maintenance strategies.

[0101] 4. The present invention can simulate various fault conditions in a control environment through a digital simulation model, test different grounding resistances and fault types, evaluate system response and rule effectiveness, and provide adequate preparation for practical applications.

[0102] 5. Through feedback loops and simulation result analysis, the present invention can continuously optimize detection rules, adapt to changing power systems and environmental conditions, and ensure the foresight and effectiveness of detection strategies.

[0103] 6. The detection rules and optimization process formed by the present invention can be used as standard operating procedures to provide training for relevant personnel, promote the inheritance of knowledge and the improvement of skills, and enhance the team's response ability to high-resistance grounding faults.

[0104] 7. Reduce operational risks. The present invention can detect faults in a timely and accurate manner, thereby reducing potential power accidents and the risk of power outages caused by faults, thereby protecting the safety of equipment and users and reducing economic losses.

[0105] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0106] Based on the same inventive concept, an embodiment of the present invention also provides a distribution network high-resistance grounding fault detection device, which can be used to implement the distribution network high-resistance grounding fault detection method described in the above embodiment, as described in the following embodiment. Since the principle of solving the problem by the distribution network high-resistance grounding fault detection device is similar to that of the distribution network high-resistance grounding fault detection method, the embodiment of the distribution network high-resistance grounding fault detection device can refer to the embodiment of the distribution network high-resistance grounding fault detection method, and the repeated parts will not be repeated. As used below, the term "unit" or "module" can be a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0107] Figure 6 is a structural block diagram of a high-resistance grounding fault detection device for a distribution network according to an embodiment of the present invention. Figure 6 As shown, in one embodiment of the present invention, the distribution network high-resistance grounding fault detection device of the present invention includes:

[0108] A data acquisition unit 1 is used to acquire the residual current measured by the toroidal current transformer installed in the substation, the residual voltage along the feeder, and the V2 / V1 ratio downstream of the high-resistance ground fault test point;

[0109] The high-resistance grounding fault detection unit 2 is used to perform high-resistance grounding fault detection on the distribution network according to the residual current, the residual voltage, the V2 / V1 ratio and a preset high-resistance grounding fault detection rule.

[0110] In one embodiment of the present invention, the high-resistance grounding fault detection rule includes: when the residual current increases, the residual voltage decreases, and the V2 / V1 ratio increases, it is determined that a high-resistance grounding fault occurs.

[0111] In one embodiment of the present invention, the distribution network high-resistance grounding fault detection device of the present invention further includes:

[0112] A laboratory test system establishment unit, used to establish a laboratory test system, wherein the laboratory test system comprises: a transformer, a busbar, a grounding reactor and a plurality of distribution feeders, wherein the busbar is connected to the reactor;

[0113] A laboratory fault simulation unit, used for simulating a high-resistance grounding fault based on the laboratory test system to obtain simulated fault data, wherein the simulated fault data includes: the residual current, the residual voltage and the V2 / V1 ratio;

[0114] The first high-resistance grounding fault detection rule determining unit is configured to determine the high-resistance grounding fault detection rule according to the simulated fault data.

[0115] In one embodiment of the present invention, the distribution network high-resistance grounding fault detection device of the present invention further includes:

[0116] A laboratory simulation model building unit, used for digitally simulating the laboratory test system to obtain a laboratory simulation model;

[0117] The first rule verification and optimization unit is used to verify and optimize the high-resistance grounding fault detection rule by simulating the high-resistance grounding fault in the laboratory simulation model.

[0118] In one embodiment of the present invention, the distribution network high-resistance grounding fault detection device of the present invention further includes:

[0119] An actual feeder fault simulation unit, used for obtaining actual fault simulation data by simulating a high-resistance grounding fault in an actual feeder, wherein the actual fault simulation data includes: the residual current, the residual voltage and the V2 / V1 ratio;

[0120] The second high-resistance grounding fault detection rule determination unit is configured to determine the high-resistance grounding fault detection rule according to the actual fault simulation data.

[0121] In one embodiment of the present invention, the distribution network high-resistance grounding fault detection device of the present invention further includes:

[0122] A feeder simulation model building unit is used to digitally simulate the actual feeder to obtain a feeder simulation model;

[0123] The second rule verification and optimization unit is used to verify and optimize the high-resistance grounding fault detection rule by simulating the high-resistance grounding fault in the feeder simulation model.

[0124] In order to achieve the above object, according to another aspect of the present application, a computer device is also provided. Figure 7 As shown, the computer device includes a memory, a processor, a communication interface and a communication bus. A computer program that can be executed on the processor is stored in the memory. When the processor executes the computer program, the steps in the above-mentioned embodiment method are implemented.

[0125] The processor may be a central processing unit (CPU). The processor may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or a combination of the above chips.

[0126] The memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer executable programs and units, such as the corresponding program units in the above method embodiments of the present invention. The processor executes various functional applications of the processor and works data processing by running the non-transitory software programs, instructions and modules stored in the memory, that is, implementing the method in the above method embodiments.

[0127] The memory may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created by the processor, etc. In addition, the memory may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory may optionally include a memory remotely arranged relative to the processor, and these remote memories may be connected to the processor via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0128] The one or more units are stored in the memory, and when executed by the processor, the method in the above embodiment is performed.

[0129] The specific details of the above-mentioned computer device can be understood by referring to the corresponding related descriptions and effects in the above-mentioned embodiments, and will not be repeated here.

[0130] In order to achieve the above-mentioned purpose, according to another aspect of the present application, a computer-readable storage medium is also provided, wherein the computer-readable storage medium stores a computer program, and the computer program implements the steps in the above-mentioned distribution network high-resistance grounding fault detection method when executed in a computer processor. Those skilled in the art can understand that the implementation of all or part of the processes in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium, and the program can include the processes of the embodiments of the above-mentioned methods when executed. Among them, the storage medium can be a disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory (Flash Memory), a hard disk (Hard Disk Drive, abbreviated as: HDD) or a solid-state drive (SSD), etc.; the storage medium can also include a combination of the above-mentioned types of memory.

[0131] In order to achieve the above-mentioned purpose, according to another aspect of the present application, a computer program product is further provided, including a computer program / instruction, which implements the steps of the above-mentioned distribution network high-resistance grounding fault detection method when executed by a processor.

[0132] Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, and optionally, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

[0133] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for detecting high-resistance grounding faults in a distribution network, characterized in that: include: Obtain the residual current measured by the toroidal current transformer installed in the substation, the residual voltage along the feeder, and the V2 / V1 ratio downstream of the high-resistance earth fault test point; The power distribution network high-resistance grounding fault detection is performed according to the residual current, the residual voltage, the V2 / V1 ratio and a preset high-resistance grounding fault detection rule.

2. The method for detecting high-resistance grounding fault in a distribution network according to claim 1, characterized in that: The high-resistance ground fault detection rule includes: when the residual current increases, the residual voltage decreases, and the V2 / V1 ratio increases, it is determined that a high-resistance ground fault occurs.

3. The method for detecting high-resistance grounding fault in a distribution network according to claim 1, characterized in that: Also includes: Establishing a laboratory test system, wherein the laboratory test system comprises: a transformer, a busbar, a grounding reactor, and a plurality of distribution feeders, wherein the busbar is connected to the reactor; Based on the laboratory test system, a high-resistance grounding fault is simulated to obtain simulated fault data, wherein the simulated fault data includes: the residual current, the residual voltage and the V2 / V1 ratio; The high-resistance grounding fault detection rule is determined according to the simulated fault data.

4. The method for detecting high-resistance grounding fault in a distribution network according to claim 3, characterized in that: Also includes: Performing digital simulation on the laboratory test system to obtain a laboratory simulation model; By simulating a high-resistance grounding fault in the laboratory simulation model, the high-resistance grounding fault detection rule is verified and optimized.

5. The method for detecting high-resistance grounding fault in a distribution network according to claim 1, characterized in that: Also includes: By performing a high-resistance grounding fault simulation in an actual feeder, actual fault simulation data is obtained, wherein the actual fault simulation data includes: the residual current, the residual voltage, and the V2 / V1 ratio; The high-resistance grounding fault detection rule is determined according to the actual fault simulation data.

6. The method for detecting high-resistance grounding fault in a distribution network according to claim 5, characterized in that: Also includes: Perform digital simulation on the actual feeder to obtain a feeder simulation model; By simulating a high-resistance grounding fault in the feeder simulation model, the high-resistance grounding fault detection rule is verified and optimized.

7. A distribution network high-resistance grounding fault detection device, characterized in that: include: A data acquisition unit for acquiring the residual current measured by the toroidal current transformer installed in the substation, the residual voltage along the feeder, and the V2 / V1 ratio downstream of the high-resistance earth fault test point; The high-resistance grounding fault detection unit is used to perform high-resistance grounding fault detection on the distribution network according to the residual current, the residual voltage, the V2 / V1 ratio and a preset high-resistance grounding fault detection rule.

8. The distribution network high-resistance grounding fault detection device according to claim 7, characterized in that: The high-resistance ground fault detection rule includes: when the residual current increases, the residual voltage decreases, and the V2 / V1 ratio increases, it is determined that a high-resistance ground fault occurs.

9. The distribution network high-resistance grounding fault detection device according to claim 7, characterized in that: Also includes: A laboratory test system establishment unit, used to establish a laboratory test system, wherein the laboratory test system comprises: a transformer, a busbar, a grounding reactor and a plurality of distribution feeders, wherein the busbar is connected to the reactor; A laboratory fault simulation unit, used for simulating a high-resistance grounding fault on the basis of the laboratory test system to obtain simulated fault data, wherein the simulated fault data includes: the residual current, the residual voltage and the V2 / V1 ratio; The first high-resistance grounding fault detection rule determining unit is configured to determine the high-resistance grounding fault detection rule according to the simulated fault data.

10. The distribution network high-resistance grounding fault detection device according to claim 9, characterized in that: Also includes: A laboratory simulation model building unit, used for digitally simulating the laboratory test system to obtain a laboratory simulation model; The first rule verification and optimization unit is used to verify and optimize the high-resistance grounding fault detection rule by simulating the high-resistance grounding fault in the laboratory simulation model.

11. The distribution network high-resistance grounding fault detection device according to claim 7, characterized in that: Also includes: An actual feeder fault simulation unit, used for obtaining actual fault simulation data by simulating a high-resistance grounding fault in an actual feeder, wherein the actual fault simulation data includes: the residual current, the residual voltage and the V2 / V1 ratio; The second high-resistance grounding fault detection rule determination unit is configured to determine the high-resistance grounding fault detection rule according to the actual fault simulation data.

12. The distribution network high-resistance grounding fault detection device according to claim 11, characterized in that: Also includes: A feeder simulation model building unit is used to digitally simulate the actual feeder to obtain a feeder simulation model; The second rule verification and optimization unit is used to verify and optimize the high-resistance grounding fault detection rule by simulating the high-resistance grounding fault in the feeder simulation model.

13. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

14. A computer-readable storage medium having a computer program / instruction stored thereon, characterized in that: When the computer program / instructions are executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

15. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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