Arc grounding fault passive-active fusion series voltage division type arc extinction method and system for power distribution network

Abstract

The application relates to the technical field of relay protection, in particular to a series voltage division type arc extinction method and system for arc ground fault of a power distribution network, which does not change the traditional resonant ground power distribution network topology structure, and proposes a passive-source-fusion arc extinction structure. On one hand, through series voltage division of the passive structure, the capacity of the active arc extinction device is effectively reduced on the basis of improving the arc extinction effect, and the poor arc extinction effect caused by excessively high outlet voltage of the active arc extinction device is avoided; on the other hand, the target compensation current value required by the active arc extinction device is calculated, the active arc extinction device is controlled to output the current meeting the target compensation current value to the neutral point, until the arc at the fault point is extinguished, and reliable arc extinction is realized. The application aims to solve the problem of how to avoid the poor arc suppression effect caused by the interruption of the compensation current due to excessively high voltage on the active device.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of relay protection, in particular to a series voltage division type arc extinction method and system for arc grounding fault of a power distribution network. BACKGROUND

[0002] With the increasing proportion of cable lines in the power distribution network, when a single-phase grounding fault occurs, a large grounding current is generated due to the significant increase of the system capacitance to the ground, the arc is difficult to extinguish by itself, and the equipment and lines are easily burned out in long-term operation, which may even form a developing fault or cause a forest fire. Therefore, it is necessary to identify and remove the fault in time when a single-phase grounding fault occurs to avoid further damage.

[0003] For the arc extinction problem of single-phase grounding fault, the commonly used scheme is to inject a compensation current or reduce the voltage by using an active arc extinction device.

[0004] However, in the traditional scheme, the active device is directly connected in parallel with the arc suppression coil, which is equivalent to a voltage source in series with an impedance model. According to Kirchhoff's law, when a single-phase grounding fault occurs, the neutral point voltage will rise to the level of the phase voltage. In order to inject the required compensation current, the arc suppression device needs to overcome the high outlet voltage of the system impedance to the ground, which results in that the outlet voltage of the active device is prone to be too high, especially in the case of high resistance grounding fault, the outlet voltage of the active device is prone to exceed its rated voltage. The high voltage will trigger the protection lock of the device itself, interrupt the compensation current output and stop the arc extinction.

[0005] In view of this, the application provides a series voltage division type arc extinction method applied to arc grounding fault of a power distribution network, which aims to avoid the problem of poor arc suppression effect caused by the interruption of compensation current due to excessive voltage on the active device. SUMMARY

[0006] The main purpose of the application is to provide a series voltage division type arc extinction method for arc grounding fault of a power distribution network, which aims to solve the problem of poor arc suppression effect caused by the interruption of compensation current due to excessive voltage on the active device.

[0007] To achieve the above purpose, the application provides a series voltage division type arc extinction method for arc grounding fault of a power distribution network, which is applied to a power distribution network including at least two-phase circuits. A first arc suppression coil and a second arc suppression coil are connected in series at the neutral point of the power distribution network. The second arc suppression coil is connected in parallel with an active arc extinction device. The method comprises the following steps:

[0008] When a single-phase ground fault of a power distribution network is detected, a fault phase voltage, a non-fault phase voltage, a power distribution network ground parameter, a first inductance value of a first arc extinguishing coil and a second inductance value of a second arc extinguishing coil are obtained, the power distribution network ground parameter comprises a ground admittance of each phase, a first ground admittance corresponding to the first arc extinguishing coil and a second ground admittance corresponding to the second arc extinguishing coil;

[0009] According to the fault phase voltage, the non-fault phase voltage, the power distribution network ground parameter, the first inductance value and the second inductance value, a target compensation current value of the active arc extinguishing device is determined, wherein the target compensation current value is a negative value.

[0010] The active arc extinguishing device is controlled to output a current meeting the target compensation current value to a neutral point until an arc at the fault point is extinguished.

[0011] Optionally, the step of determining the target compensation current value of the active arc extinguishing device according to the fault phase voltage, the non-fault phase voltage, the power distribution network ground parameter, the first inductance value and the second inductance value comprises:

[0012] According to the fault phase voltage, the first inductance value and the second inductance value, a target voltage value is determined.

[0013] According to the target voltage value, the non-fault phase voltage and the power distribution network ground parameter, the target compensation current value is determined.

[0014] Optionally, the step of determining the target voltage value according to the fault phase voltage, the first inductance value and the second inductance value comprises:

[0015]

[0016] In the formula, is the target voltage, is the fault phase voltage, L1 is the first inductance value and L2 is the second inductance value.

[0017] Optionally, the power distribution network comprises a three-phase circuit of A, B and C phases, the power distribution network ground parameter comprises a ground admittance of the A phase, a ground admittance of the B phase, a ground admittance of the C phase, the first ground admittance and the second ground admittance, the A phase is the fault phase, the B and C phases are the non-fault phases, and a calculation expression of the target compensation current value is:

[0018]

[0019] In the formula, is the target voltage, is the target compensation current, , , respectively, L1 is a first inductance value, L2 is a second inductance value, Y1 is a first ground admittance, Y2 is a second ground admittance, is an A-phase voltage, , is a B-phase voltage and a C-phase voltage.

[0020] Optionally, the step of detecting the single-phase ground fault in the power distribution network comprises:

[0021] collecting a zero-sequence voltage and a phase voltage value of each phase in the power distribution network;

[0022] when it is monitored that the zero-sequence voltage is greater than or equal to a preset proportion of the phase voltage value, it is determined that a single-phase ground fault occurs in the power distribution network, and a corresponding phase of the phase voltage value is the fault phase;

[0023] otherwise, it is determined that no single-phase ground fault occurs in the power distribution network.

[0024] Optionally, the step of controlling the active arc extinguishing device to output a current satisfying the target compensation current value to the fault point comprises:

[0025] adjusting the injection current of the active arc extinguishing device to be equal to the target compensation current value by a negative feedback regulation method;

[0026] injecting the injection current to the neutral point by a closed-loop control method.

[0027] In addition, to achieve the above-mentioned purpose, the present application also provides a multi-source fusion arc extinguishing device, which comprises: a first arc extinguishing coil and a second arc extinguishing coil arranged in series, and an active arc extinguishing device connected in parallel with the second arc extinguishing coil;

[0028] wherein, when the multi-source fusion arc extinguishing device detects that a single-phase ground fault occurs in a power distribution network, it outputs a current value of the target compensation current value in the passive-active fusion series voltage division type arc extinguishing method for arc ground fault of the power distribution network as described above to the neutral point, until the arc at the fault point is extinguished.

[0029] In addition, to achieve the above-mentioned purpose, the present application also provides an arc extinguishing system, which comprises:

[0030] a data acquisition module, configured to acquire a fault phase voltage, a non-fault phase voltage, a power distribution network ground parameter, a first inductance value of a first arc extinguishing coil and a second inductance value of a second arc extinguishing coil in a power distribution network, wherein the power distribution network ground parameter comprises a ground admittance of each phase, a first ground admittance corresponding to the first arc extinguishing coil and a second ground admittance corresponding to the second arc extinguishing coil;

[0031] The fault discrimination starting module is configured to, when detecting that a single-phase ground fault occurs in the power distribution network, acquire the fault-phase voltage, the non-fault-phase voltage, the ground parameter of the power distribution network, the first inductance value of the first arc-extinguishing coil and the second inductance value of the second arc-extinguishing coil collected in the data acquisition module;

[0032] The compensation current generation control module is configured to determine a target compensation current value of the active arc-extinguishing device according to the fault-phase voltage, the non-fault-phase voltage, the ground parameter of the power distribution network, the first inductance value and the second inductance value, wherein the target compensation current value is a negative value.

[0033] The arc-extinguishing module is configured to control the active arc-extinguishing device to output a current value meeting the target compensation current value to the neutral point until the arc at the fault point is extinguished.

[0034] In addition, to achieve the above-mentioned purpose, the present application further provides a computer system, which comprises a memory, a processor and a computer program stored on the memory and executable on the processor, and the computer program implements the steps of the power distribution network arc ground fault passive-active fusion series voltage division type arc-extinguishing method according to any one of the above-mentioned embodiments when executed by the processor.

[0035] In addition, to achieve the above-mentioned purpose, the present application further provides a computer readable storage medium, which stores a computer program, and the computer program implements the steps of the power distribution network arc ground fault passive-active fusion series voltage division type arc-extinguishing method according to any one of the above-mentioned embodiments when executed by a processor.

[0036] The present application has at least the following beneficial effects:

[0037] 1. Without changing the traditional resonant grounding power distribution network topology, a passive-active fusion arc-extinguishing structure is proposed, and through series voltage division of the passive structure, the capacity of the active arc-extinguishing device is effectively reduced on the basis of improving the arc-extinguishing effect, thereby avoiding the poor arc-extinguishing effect caused by the excessively high outlet voltage of the active arc-extinguishing device.

[0038] 2. The target compensation current value required by the active arc-extinguishing device is calculated, the active arc-extinguishing device is controlled to output a current meeting the target compensation current value to the neutral point, and the arc at the fault point is extinguished until the arc is extinguished, thereby realizing reliable arc extinction.

[0039] 3. Compared with the traditional topology structure, only an isolation transformer is used without a step-up transformer structure, and the influence of the step-up transformer error is eliminated. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 It is a flowchart of a first embodiment of the power distribution network arc ground fault passive-active fusion series voltage division type arc-extinguishing method of the present application.

[0041] Figure 2 The closed-loop control logic block diagram related to the embodiment of the present application;

[0042] Figure 3 The power distribution network arc simulation model schematic diagram related to the embodiment of the present application;

[0043] Figure 4 The active arc extinction topology diagram related to the embodiment of the present application;

[0044] Figure 5 The fault phase voltage waveform schematic diagram when arc grounding fault occurs related to the embodiment of the present application;

[0045] Figure 6 The fault point current waveform schematic diagram when arc grounding fault occurs related to the embodiment of the present application;

[0046] Figure 7 The neutral point voltage waveform schematic diagram when arc grounding fault occurs related to the embodiment of the present application;

[0047] Figure 8 The fault phase voltage waveform schematic diagram when arc extinction starts related to the embodiment of the present application;

[0048] Figure 9 The fault point current waveform schematic diagram when arc extinction starts related to the embodiment of the present application;

[0049] Figure 10 The neutral point voltage waveform schematic diagram when arc extinction starts related to the embodiment of the present application;

[0050] Figure 11 The arc extinction system architecture schematic diagram related to the embodiment of the present application;

[0051] Figure 12 The hardware running environment architecture schematic diagram of the computer system related to the embodiment of the present application.

[0052] The implementation of the present application, functional features and advantages will be further described with reference to the embodiments, the accompanying drawings. DETAILED DESCRIPTION

[0053] In order to better understand the above technical solutions, the exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0054] First embodiment

[0055] In this embodiment, the power distribution network includes at least two-phase circuit, the neutral point of the power distribution network is provided with a first arc suppression coil L1 and a second arc suppression coil L2 in series, and the second arc suppression coil L2 is connected in parallel with an active arc suppression device.

[0056] It should be noted that by splitting the passive arc suppression coil into series inductances L1 and L2, the active device only bears part of the voltage. The target voltage is redefined as:

[0057]

[0058] By reasonably configuring the ratio of L1 / L2, the voltage borne by the active arc suppression device can be reduced to L2 / (L1+L2) times of the original structure.

[0059] Further, in this embodiment, with reference to Figure 1 , the power distribution network arc grounding fault passive-active fusion series voltage division type arc suppression method includes the following steps:

[0060] Step S10, when detecting that a single-phase grounding fault occurs in the power distribution network, obtaining the fault phase voltage, the non-fault phase voltage, the power distribution network ground parameter, the first inductance value of the first arc suppression coil and the second inductance value of the second arc suppression coil, the power distribution network ground parameter includes the ground admittance of each phase, the first ground admittance corresponding to the first arc suppression coil and the second ground admittance corresponding to the second arc suppression coil;

[0061] In this step, when detecting that a single-phase grounding fault occurs in the power distribution network, the parameters required for calculating the compensation current value of the active arc suppression device are obtained, including the fault phase voltage, the non-fault phase voltage, the power distribution network ground parameter, the first inductance value of the first arc suppression coil and the second inductance value of the second arc suppression coil, the power distribution network ground parameter includes the ground admittance of each phase, the first ground admittance corresponding to the first arc suppression coil and the second ground admittance corresponding to the second arc suppression coil.

[0062] In some optional embodiments, how to detect that a single-phase grounding fault occurs in the power distribution network:

[0063] Collecting the zero sequence voltage and the phase voltage value of each phase in the power distribution network;

[0064] When it is monitored that the zero sequence voltage is greater than or equal to the preset proportion of the phase voltage value, it is judged that a single-phase grounding fault occurs in the power distribution network, and the corresponding phase of the phase voltage value is the fault phase;

[0065] Otherwise, it is judged that no single-phase grounding fault occurs in the power distribution network.

[0066] In some optional embodiments, the preset proportion can be 15%, and if the zero sequence voltage is U N , the phase voltage is Um If , the line has a ground fault, and the fault phase is U m If , the line has no ground fault.

[0067] Step S20, determining a target compensation current value of the active arc extinguishing device according to the fault phase voltage, the non-fault phase voltage, the power distribution network ground parameter, the first inductance value and the second inductance value, wherein the target compensation current value is a negative value.

[0068] In this step, the obtained parameters are used to calculate the target compensation current value, wherein the obtained target compensation current value is defined as a negative value, i.e. a current opposite to the direction of the fault current of the neutral point.

[0069] In some optional embodiments, step S20 specifically comprises:

[0070] Step S21, determining a target voltage value according to the fault phase voltage, the first inductance value and the second inductance value.

[0071] Further and optionally, the calculation expression of the target voltage value is:

[0072]

[0073] In the formula, is the target voltage, is the fault phase voltage, L1 is the first inductance value, and L2 is the second inductance value.

[0074] Step S22, determining the target compensation current value according to the target voltage value, the non-fault phase voltage and the power distribution network ground parameter.

[0075] Further and optionally, the power distribution network comprises a three-phase circuit of A, B and C, the power distribution network ground parameter comprises A-phase ground admittance, B-phase ground admittance, C-phase ground admittance, and the first ground admittance and the second ground admittance, A-phase is the fault phase, and B-phase and C-phase are the non-fault phases, and the calculation expression of the target compensation current value is:

[0076]

[0077] In the formula, is the target voltage, is the target compensation current, , , are A-phase ground admittance, B-phase ground admittance and C-phase ground admittance respectively, L1 is the first inductance value, L2 is the second inductance value, Y1 is the first ground admittance, and Y2 is the second ground admittance. This refers to the voltage of phase A (i.e., the voltage of the faulty phase). , These are the voltages of phase B and phase C.

[0078] Step S30: Control the active arc extinguishing device to output a current that meets the target compensation current value to the neutral point until the arc at the fault point is extinguished.

[0079] In this embodiment, refer to Figure 2 The diagram shows the closed-loop control logic block diagram in this embodiment. This is the input reference current; This is the actual measured current value; For the transfer function of the PI controller; This is the transfer function between the output current and the injected voltage; This is the inverter proportional gain; This is the neutral point voltage.

[0080] In some alternative implementations, the target compensation current value is calculated in real time by a DSP processor and output as a current command signal in a three-phase stationary coordinate system. A Hall current sensor is installed at the inverter output in the distribution network. A second-order low-pass filter is used to suppress high-frequency noise in the Hall current sensor and retain the fundamental component. The fundamental component is modulated by space vector modulation and the regulator output is converted into IGBT drive pulses. The compensation current is injected into the neutral point through an isolation transformer.

[0081] In the technical solution provided in this embodiment, without changing the traditional resonant grounding distribution network topology, a passive-multi-source phase-integrated arc extinguishing structure is proposed. By using the series voltage division of the passive structure, the arc extinguishing effect is improved while effectively reducing the capacity of the active arc extinguishing device. This avoids the arc extinguishing effect being poor due to excessively high output voltage of the active arc extinguishing device. At the same time, the target compensation current value required by the active arc extinguishing device is calculated, and the active arc extinguishing device is controlled to output a current to the neutral point that meets the target compensation current value until the arc at the fault point is extinguished, thus achieving reliable arc extinguishing.

[0082] Second Embodiment

[0083] Based on the first embodiment, this embodiment provides a method such as Figure 3The power distribution network arc simulation model shown, the model includes: 110kV / 10kV substation has six return line, overhead line has 4, respectively, L1=8km, L2=24km, L4=16km, L6=12km, there are 2 pure cable line, respectively, L3=16km, L5=15km. Among them, the positive sequence impedance of overhead line is: R1=0.45Ω / km, L1=1.172mH / km, C1=6.1nF / km, zero sequence impedance is: R0=0.7Ω / km, L0=3.91mH / km, C0=3.8nF / km; the positive sequence impedance of cable feeder is: R1=0.075Ω / km, L1=0.254mH / km, C1=318nF / km, the zero sequence impedance is: R0=0.102Ω / km, L0=0.892mH / km, C0=212nF / km.

[0084] Referring to Figure 4 , when the switch is closed, the power distribution network is an arc suppression coil L1, arc suppression coil L2 in series arc suppression coil grounding system, after detecting that a single-phase grounding fault occurs, the switch is closed, the active arc suppression is put into operation, and the inverter control mode of the active arc suppression adopts double closed loop control. In PSCAD, it is set that the A-phase of L4 feeder occurs arc grounding fault at 0.515s, the active arc suppression is put into operation at t=0.615s, and the fault duration is 1s.

[0085] Further, based on the power distribution network arc simulation model built in the embodiment, the active arc suppression fault phase voltage waveform diagram, the active arc suppression fault point current waveform diagram, the active arc suppression neutral point voltage waveform diagram at the time of arc grounding fault, the fault phase voltage waveform diagram at the time of arc starting, the fault point current waveform diagram at the time of arc starting and the neutral point voltage waveform diagram at the time of arc starting are respectively sampled as shown in Figures 5-10 .

[0086] It can be known from Figure 5 and Figure 8 that the fault phase voltage decreases from U m to <10% at t=0.515s, which proves that the active arc suppression realizes voltage forced zero.

[0087] It can be known from Figure 6 and Figure 9 that the arc starting is at t=0.615s, and the fault point current decreases from >100A to <5A (in 1 cycle), which verifies the rapidity of the current type arc suppression.

[0088] It can be known from Figure 6 and Figure 10 that at t=0.515s, the neutral point voltage UN从 30%Um changes to 5%Um, indicating that the series voltage division effectively suppresses the neutral point overvoltage.

[0089] In addition, the embodiment also provides a multi-source fusion arc extinction device, which comprises a first arc suppression coil and a second arc suppression coil arranged in series, and an active arc extinction device connected in parallel with the second arc suppression coil.

[0090] The multi-source fusion arc extinction device outputs a current value of the target compensation current value in the passive-active fusion series voltage division type arc extinction method for the arc ground fault of the power distribution network to a neutral point until the arc at the fault point is extinguished.

[0091] In addition, with reference to Figure 11 , the embodiment also provides an arc extinction system, which comprises:

[0092] A data acquisition module 100 is configured to acquire a fault phase voltage, a non-fault phase voltage, a power distribution network ground parameter, a first inductance value of a first arc suppression coil and a second inductance value of a second arc suppression coil, wherein the power distribution network ground parameter comprises a ground admittance of each phase, a first ground admittance corresponding to the first arc suppression coil and a second ground admittance corresponding to the second arc suppression coil.

[0093] A fault discrimination starting module 200 is configured to acquire the fault phase voltage, the non-fault phase voltage, the power distribution network ground parameter, the first inductance value of the first arc suppression coil and the second inductance value of the second arc suppression coil acquired by the data acquisition module when detecting that a single-phase ground fault occurs in the power distribution network.

[0094] A compensation current generation control module 300 is configured to determine a target compensation current value of the active arc extinction device according to the fault phase voltage, the non-fault phase voltage, the power distribution network ground parameter, the first inductance value and the second inductance value, wherein the target compensation current value is a negative value.

[0095] An arc extinction module 400 is configured to control the active arc extinction device to output a current value meeting the target compensation current value to a neutral point until the arc at the fault point is extinguished.

[0096] As an implementation scheme, Figure 12 The embodiment of the present application relates to the architecture schematic diagram of a hardware running environment of a computer system.

[0097] As Figure 12As shown, the computer system can include a processor 1001, such as a CPU, a memory 1005, a user interface 1003, a network interface 1004, and a communication bus 1002. The communication bus 1002 is used to realize the connection communication between the components. The user interface 1003 can include a display screen (Display), an input unit such as a keyboard (Keyboard), and the optional user interface 1003 can also include a standard wired interface, a wireless interface. The network interface 1004 can optionally include a standard wired interface, a wireless interface (such as a WI-FI interface). The memory 1005 can be a high-speed RAM memory, or a stable memory (non-volatile memory) such as a disk memory. The memory 1005 can also be a storage device independent of the aforementioned processor 1001.

[0098] Those skilled in the art can understand that, Figure 12 The computer system architecture shown in the embodiment does not constitute a limitation on the computer system, and can include more or fewer components than shown, or combine certain components, or different component arrangements.

[0099] As Figure 12 As shown, the memory 1005 as a storage medium can include an operating system, a network communication module, a user interface module, and a computer program. The operating system is a program that manages and controls the hardware and software resources of the computer system, and the running of the computer program and other software or programs.

[0100] In Figure 12 In the computer system shown, the user interface 1003 is mainly used to connect the terminal and communicate data with the terminal; the network interface 1004 is mainly used for the background server and communicates data with the background server; and the processor 1001 can be used to call the computer program stored in the memory 1005.

[0101] In the embodiment, the computer system includes a memory 1005, a processor 1001, and a computer program stored on the memory and executable on the processor, wherein:

[0102] When the processor 1001 calls the computer program stored in the memory 1005, the following operations are performed:

[0103] When a single-phase ground fault of the power distribution network is detected, the fault phase voltage, the non-fault phase voltage, the power distribution network ground parameter, the first inductance value of the first arc-extinguishing coil, and the second inductance value of the second arc-extinguishing coil are obtained, the power distribution network ground parameter includes the ground admittance of each phase, the first ground admittance corresponding to the first arc-extinguishing coil, and the second ground admittance corresponding to the second arc-extinguishing coil;

[0104] determine a target compensation current value of the active arc-extinguishing device according to the fault-phase voltage, the non-fault-phase voltage, the power distribution network grounding parameter, the first inductance value and the second inductance value, wherein the target compensation current value is a negative value;

[0105] control the active arc-extinguishing device to output a current to the neutral point, wherein the current satisfies the target compensation current value, until the arc at the fault point is extinguished.

[0106] When the processor 1001 invokes the computer program stored in the memory 1005, the following operations are performed:

[0107] determine a target voltage value according to the fault-phase voltage, the first inductance value and the second inductance value;

[0108] determine the target compensation current value according to the target voltage value, the non-fault-phase voltage and the power distribution network grounding parameter.

[0109] When the processor 1001 invokes the computer program stored in the memory 1005, the following operations are performed:

[0110] acquire phase voltage values of each phase in the power distribution network;

[0111] when it is monitored that the phase voltage value is greater than a preset phase voltage threshold value, it is determined that a single-phase grounding fault occurs in the power distribution network, and the phase corresponding to the phase voltage value is the fault phase.

[0112] When the processor 1001 invokes the computer program stored in the memory 1005, the following operations are performed:

[0113] adjust the injection current of the active arc-extinguishing device to be equal to the target compensation current value by a negative feedback regulation method;

[0114] inject the injection current to the neutral point by a closed-loop control method.

[0115] In addition, those skilled in the art can understand that all or part of the processes in the method for implementing the above-mentioned embodiments can be completed by a computer program instructing related hardware. The computer program includes program instructions, and the computer program can be stored in a storage medium, which is a computer readable storage medium. The program instructions are executed by at least one processor in a computer system to implement the process steps of the above-mentioned embodiments.

[0116] Therefore, the application further provides a computer readable storage medium, which stores a computer program. When the computer program is executed by a processor, each step of the power distribution network arc grounding fault passive-active fusion series voltage division type arc-extinguishing method is implemented.

[0117] The computer readable storage medium can be a U disk, a mobile hard disk, a Read-Only Memory (ROM), a magnetic disk or an optical disk, or various computer readable storage media that can store program codes.

[0118] It should be noted that the storage medium provided by the embodiments of the present application is a storage medium used for implementing the method of the embodiments of the present application. Therefore, based on the method introduced in the embodiments of the present application, the specific structure and modification of the storage medium can be understood by those skilled in the art, and thus will not be described here. Any storage medium used by the method of the embodiments of the present application belongs to the scope of protection of the present application.

[0119] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system or a computer program product. Therefore, the present application can adopt a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware aspects. Moreover, the present application can adopt 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 codes.

[0120] The present application is described with reference to flowcharts and / or block diagrams according to the method, device (system) and computer program product of the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing devices to produce a machine, so that the instructions executed by the computer or other programmable data processing devices produce a device for implementing the functions specified in the flowcharts and / or block diagrams. Figure 1 The functions specified in one flow or multiple flows and / or blocks Figure 1 The functions specified in one flow or multiple flows and / or blocks

[0121] These computer program instructions can also be stored in a computer readable storage medium that can guide the computer or other programmable data processing devices to work in a specific way, so that the instructions stored in the computer readable storage medium produce a manufactured product including instruction devices, which implement the functions specified in the flowcharts and / or block diagrams. Figure 1 The functions specified in one flow or multiple flows and / or blocks Figure 1 The functions specified in one flow or multiple flows and / or blocks

[0122] These computer program instructions can also be loaded into a computer or other programmable data processing devices, so that a series of operational steps are performed on the computer or other programmable devices, to generate computer-implemented processes, thus the instructions executed on the computer or other programmable devices provide processes for implementing the functions specified in the flowchart Figure 1 one or more flows and / or blocks Figure 1 one or more blocks or multiple blocks.

[0123] It is noted that in the claims the word "comprising" does not exclude not having other parts than those specified in the claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. It is further noted that the application can be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the system claims enumerating several means, several of these means can be embodied by one and the same item of hardware. The implementation by means of hardware and software of the application relates to the application as such. The application can be implemented by means of hardware only, but also can be implemented by means of software only. The application can be implemented by means of hardware and software together. The application relates to software and hardware, such as computer program or a computer program element.

[0124] Although the preferred embodiments of the application have been described, those skilled in the art will be able to make additional modifications and variations to these embodiments without departing from the scope of the application. Accordingly, it is intended to embrace all such future modifications and variations as fall within the scope of the application. Accordingly, the appended claims as

[0125] Obviously, many modifications and variations of the present application are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A series voltage divider arc suppression method for arc-ground faults in distribution networks, combining passive and active approaches, applicable to distribution networks comprising at least two phase circuits, characterized in that... A first arc-suppression coil and a second arc-suppression coil are connected in series at the neutral point of the power distribution network. The second arc-suppression coil is connected in parallel with an active arc-suppression device. The method includes the following steps: When a single-phase ground fault is detected in the distribution network, the fault phase voltage, the non-fault phase voltage, the distribution network ground parameters, the first inductance value of the first arc suppression coil and the second inductance value of the second arc suppression coil are obtained. The distribution network ground parameters include the ground admittance of each phase, the first ground admittance corresponding to the first arc suppression coil and the second ground admittance corresponding to the second arc suppression coil. The target compensation current value of the active arc suppression device is determined based on the fault phase voltage, the non-fault phase voltage, the distribution network ground parameters, the first inductance value, and the second inductance value, wherein the target compensation current value is negative. The active arc extinguishing device is controlled to output a current to the neutral point that meets the target compensation current value until the arc at the fault point is extinguished. The step of determining the target compensation current value of the active arc suppression device based on the fault phase voltage, the non-fault phase voltage, the distribution network ground parameters, the first inductance value, and the second inductance value includes: The target voltage value is determined based on the fault phase voltage, the first inductance value, and the second inductance value; The target compensation current value is determined based on the target voltage value, the non-faulty phase voltage, and the distribution network ground parameters; The step of determining the target voltage value based on the fault phase voltage, the first inductance value, and the second inductance value includes: ； In the formula, For the target voltage, L1 is the voltage of the fault phase, L2 is the value of the first inductance, and L1 is the value of the second inductance. The distribution network includes three-phase circuits A, B, and C. The distribution network's ground parameters include the ground admittance of phase A, phase B, and phase C, as well as the first and second ground admittances. Assuming phase A is the faulty phase and phases B and C are the non-faulty phases, the calculation expression for the target compensation current value is: ； In the formula, For the target voltage, To compensate for the target current, , , These represent the admittances relative to ground (A), B, and C, respectively; L1 is the first inductance value; L2 is the second inductance value; Y1 is the first admittance to ground; and Y2 is the second admittance to ground. This is the voltage of phase A. , These are the voltages of phase B and phase C.

2. The series voltage divider arc suppression method for passive-active fusion of arc grounding faults in power distribution networks as described in claim 1, characterized in that, The detection steps for a single-phase ground fault in the power distribution network include: Collect the zero-sequence voltage and the phase voltage values ​​of each phase in the distribution network; When the zero-sequence voltage is detected to be greater than or equal to a preset proportion of the phase voltage value, it is determined that a single-phase ground fault has occurred in the distribution network, and the phase corresponding to the phase voltage value is the faulty phase; Otherwise, it is determined that no single-phase grounding fault has occurred in the power distribution network.

3. The series voltage divider arc suppression method for passive-active fusion of arc grounding faults in power distribution networks as described in claim 1, characterized in that, The step of controlling the active arc suppression device to output a current to the fault point that meets the target compensation current value includes: The injection current of the active arc suppression device is adjusted to be equal to the target compensation current value by means of negative feedback adjustment method; The injection current is injected into the neutral point using a closed-loop control method.

4. A multi-source fusion arc suppression device, characterized in that, The multi-source fusion arc suppression device includes: a first arc suppression coil and a second arc suppression coil connected in series, and an active arc suppression device connected in parallel with the second arc suppression coil; When the multi-source fusion arc extinguishing device detects a single-phase ground fault in the distribution network, it outputs the target compensation current value of the series voltage divider arc extinguishing method for passive-active fusion of arc ground faults in the distribution network as described in claim 1 to the neutral point until the arc at the fault point is extinguished.

5. A system for implementing the series voltage divider arc suppression method for passive-active fusion of arc grounding faults in power distribution networks as described in claim 1, characterized in that, The system includes: The data acquisition module is used to acquire the fault phase voltage, non-fault phase voltage, distribution network ground parameters, first inductance value of the first arc suppression coil and second inductance value of the second arc suppression coil in the distribution network. The distribution network ground parameters include the ground admittance of each phase, the first ground admittance corresponding to the first arc suppression coil and the second ground admittance corresponding to the second arc suppression coil. The fault detection start-up module is used to acquire the fault phase voltage, non-fault phase voltage, distribution network to ground parameters, first inductance value of the first arc suppression coil and second inductance value of the second arc suppression coil when a single-phase ground fault is detected in the distribution network. The compensation current generation control module is used to determine the target compensation current value of the active arc suppression device based on the fault phase voltage, the non-fault phase voltage, the distribution network ground parameters, the first inductance value, and the second inductance value, wherein the target compensation current value is negative. The arc suppression module is used to control the active arc suppression device to output a current value that meets the target compensation current value to the neutral point until the arc at the fault point is extinguished.

6. A computer system, characterized in that, The computer system includes: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the computer program is executed by the processor, it implements the steps of the series voltage divider arc suppression method for passive-active fusion of arc grounding faults in distribution networks as described in any one of claims 1 to 3.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the series voltage divider arc suppression method for passive-active fusion of arc grounding faults in power distribution networks as described in any one of claims 1 to 3.

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