A flexible switching method for real-time fault of power distribution network

Abstract

The application discloses a kind of distribution network true type fault flexible switching method, comprising: setting n fault points, and obtaining fault simulation demand;After matching the simulation demand, further actual demand is obtained;According to the actual demand, the trigger time strategy of fault simulation is generated.The distribution network true type fault flexible switching method provided by the application solves the problem that the previous method cannot simulate multiple point faults simultaneously, reduces the amount of manual operation and the workload of manual wiring, and improves the switching efficiency of fault points.It can realize the simultaneous and different time simulation of same name phase grounding fault and different name phase grounding fault, and can also realize the simultaneous simulation of single-phase grounding fault and short-circuit grounding fault, achieving more complex distribution network fault condition simulation.

Description

Technical Field

[0001] This invention relates to the field of fault switching technology, specifically a flexible fault switching method for distribution networks. Background Technology

[0002] With the increasing demands for power supply reliability and the accuracy of distribution network fault handling by power grid companies, as well as the deepening development of primary and secondary integration technology, how to conduct realistic simulations of fault conditions in medium and low voltage distribution networks and carry out efficient and convenient on-grid verification of new equipment and technologies has become an urgent problem to be solved. Distribution network real-scale test fields, as a platform that can provide an on-grid verification environment for key distribution network equipment and new forms and technologies, are receiving increasing attention from power research institutes and even universities.

[0003] A true-scale distribution network test site utilizes real distribution network electrical equipment to create a simulated environment consistent with actual distribution network operation. This environment simulates various fault conditions such as single-phase grounding and short circuits under laboratory conditions, allowing for the testing and verification of new equipment and technologies in the distribution network to ensure their safe and stable operation after grid connection and improve power supply reliability. Currently, major domestic distribution network test sites use manual wiring to connect fault simulation devices, resulting in complex wiring and low testing efficiency. Furthermore, due to the limited number of fault simulation devices, they must be manually moved to different fault locations, increasing the workload of setting up the fault testing environment and hindering rapid deployment of a true-scale distribution network fault testing environment. Therefore, to address the problem of inflexible switching during true-scale distribution network fault testing, which leads to low testing efficiency for integrated primary and secondary distribution network equipment and single-phase grounding fault handling devices, a method that enables flexible switching during true-scale distribution network fault testing is needed. Summary of the Invention

[0004] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0005] In view of the above-mentioned problems, the present invention is proposed.

[0006] Therefore, the technical problem solved by the present invention is that the existing fault switching method cannot simultaneously simulate single-phase ground faults and short-circuit faults, and is not flexible enough.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for flexible switching of real-type faults in a distribution network, comprising:

[0008] Set n fault points and obtain fault simulation requirements; after matching the simulation requirements, obtain further actual requirements; generate a fault simulation triggering time strategy based on the actual requirements.

[0009] As a preferred embodiment of the flexible switching method for real-type faults in the distribution network described in this invention, the fault points include: a three-phase line connected by a cable on the incoming side of the pole-mounted circuit breaker of a 10kV overhead line to form a fault access point; the cable of the fault access point extends to the hardened ground under the pole and connects to a multi-point fault access switching device; there are two fault access busbars, each connecting half of the total number of fault points; the fault access busbars are connected by two sets of pole-mounted switches 1 and 2.

[0010] As a preferred embodiment of the flexible switching method for real-world faults in the distribution network described in this invention, the fault point further includes a multi-point fault access switching device for connecting the fault access point and the fault access bus, mainly composed of high-voltage contactors. To adapt to a 10kV voltage level distribution network real-world test field, the high-voltage contactors use a rated operating voltage of 12kV, and each multi-point fault access switching device uses three high-voltage contactors to achieve fault access for the three-phase lines A, B, and C.

[0011] As a preferred embodiment of the flexible switching method for real-type faults in the distribution network described in this invention, the fault access bus is connected by two sets of pole-mounted circuit breakers. When pole-mounted switch 1 is closed and pole-mounted switch 2 is open, the short-circuit fault simulation device is connected to the fault bus 1; when pole-mounted switch 1 is open and pole-mounted switch 2 is closed, the short-circuit fault simulation device is connected to the fault bus 2; when pole-mounted switch 1 is open and pole-mounted switch 2 is open, the short-circuit fault simulation device is disconnected.

[0012] As a preferred embodiment of the flexible switching method for real-world faults in the distribution network described in this invention, the fault simulation device is used to simulate the fault types in the real-world test of the distribution network, including short-circuit fault simulation device and single-phase ground fault simulation device; the short-circuit fault simulation device is used to simulate two-phase short-circuit and three-phase short-circuit faults in the distribution network; the single-phase ground fault simulation device is used to simulate A-phase ground fault, B-phase ground fault, and C-phase ground fault; when conducting the simulation of a single-phase ground fault of the same phase, the tie switch of the fault access bus is disconnected, and pole-mounted switch 1 and pole-mounted switch 2 are disconnected; the control switch of the single-phase ground fault device of the fault access bus 1 is controlled to be closed, and the control switch of the single-phase ground fault device of the fault access bus 2 is controlled to be closed; one fault point is selected from the n / 2 fault points of the fault access bus 1 and a ground fault phase is set, and the fault is selected from the n / 2 fault points of the fault access bus 2. Select one fault point and set the same ground fault phase; simulate the same-phase ground fault by setting the fault trigger time; if the set trigger time is different, simulate the same-phase ground fault at different times; when simulating the opposite-phase single-phase ground fault, disconnect the tie switch of the fault access bus, disconnect pole-mounted switch 1 and pole-mounted switch 2; control the single-phase ground fault device control switch of fault access bus 1 to close, and control the single-phase ground fault device control switch of fault access bus 2 to close; select one fault point from n / 2 fault points of fault access bus 1 and set the ground fault phase, select one fault point from n / 2 fault points of fault access bus 2 and set a different ground fault phase; simulate the opposite-phase ground fault by setting the fault trigger time, and simulate the opposite-phase ground fault at different times if the set trigger time is different.

[0013] As a preferred embodiment of the flexible switching method for real-world faults in the distribution network described in this invention, the fault control includes: before entering fault simulation, analyzing the initial settings and retrieving historical settings for trigger times; obtaining simulation requirements, matching simulation effects that can achieve fault simulation and corresponding trigger times from historical records based on the simulation requirements; obtaining recommended setting values ​​for trigger times through further selection based on actual requirements; if the obtained recommended setting value meets the actual requirements, directly importing the recommended setting value for trigger times; if the recommended setting value is greater than the actual requirement's time limit T, adjusting the recommended setting value for trigger times according to the actual requirements, using a preset adjustment step size t. n Adjust the recommended trigger time setting until it meets the actual time limit requirements; if the preset adjustment step size t is used... n If adjusting the recommended trigger time setting fails to precisely meet the actual time limit T, the output, after step size adjustment, will exceed Tt. n Furthermore, the fault access was executed as a set value that did not exceed the actual requirement T trigger time.

[0014] As a preferred embodiment of the flexible switching method for real-world faults in the distribution network described in this invention, the requirements include: retrieving information from historical records that matches the fault effects of the simulated requirements; outputting the control effect and the corresponding set trigger time; and classifying all trigger times that meet the simulated requirements according to their corresponding set trigger times; classifying trigger times that can stably access the fault, stabilize the circuit's measurement data, and record stable measurement data as Category 1 and obtaining the shortest trigger time as a recommended setting value for Category 1; classifying trigger times that can achieve fault access but cannot record stable measurement data as Category 2 and obtaining the shortest trigger time as a recommended setting value for Category 2; and setting a step size t for the fault switching strategy. n The step size for type I is t1, and the step size for type II is t2. If the actual requirement is to be able to stably connect to the fault, stabilize the circuit's measurement data, and record stable measurement data, and the recommended setting value for type I is greater than T, then the trigger time is adjusted by t1. If the actual requirement is only fault access and the recommended setting value for type II is greater than T, then the trigger time is adjusted by t2.

[0015] A flexible fault switching system for a distribution network employing any of the methods described in this invention is characterized by: a demand acquisition unit acquiring simulated demands for flexible fault switching and transmitting the demands to a demand analysis unit; a demand analysis unit generating a trigger time setting value based on the demands and generating a fault switching command based on the setting value; and a fault access switching unit executing fault access switching according to the fault switching command.

[0016] A computer device includes: a memory and a processor; the memory stores a computer program, characterized in that: when the processor executes the computer program, it implements the steps of the method described in any one of the present invention.

[0017] A computer-readable storage medium having a computer program stored thereon, characterized in that: when the computer program is executed by a processor, it implements the steps of the method described in any one of the present invention.

[0018] The beneficial effects of this invention are as follows: The flexible switching method for real-type faults in distribution networks provided by this invention solves the problem that previous methods could not simulate multiple faults simultaneously, reduces the amount of manual operation and wiring work, and improves the switching efficiency of fault points. It can simulate simultaneous and different times of same-phase grounding faults and different-phase grounding faults, and can also simulate single-phase grounding faults and short-circuit grounding faults simultaneously, realizing the simulation of more complex distribution network fault conditions. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0020] Figure 1 This is an overall flowchart of a flexible switching method for real-type faults in a distribution network, provided in the first embodiment of the present invention.

[0021] Figure 2 This is a schematic diagram of the overhead line fault access point in a flexible switching method for real-type faults in a distribution network provided in the first embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the cable line fault access point in a flexible switching method for real-type faults in a power distribution network provided in the first embodiment of the present invention;

[0023] Figure 4 This is a diagram of a multi-point fault access switching device in a flexible switching method for real-type faults in a distribution network provided in the first embodiment of the present invention;

[0024] Figure 5 This is a diagram illustrating the connection method between two fault access buses in a flexible switching method for real-type faults in a distribution network, provided in the first embodiment of the present invention.

[0025] Figure 6 A schematic diagram of grounding faults of the same phase and different phases provided in the first embodiment of the present invention for a flexible switching method for real-type faults in a distribution network;

[0026] Figure 7 This is a schematic diagram of flexible switching of real-type faults in a distribution network flexible switching method provided in the second embodiment of the present invention. Detailed Implementation

[0027] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0028] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0029] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0030] This invention is described in detail with reference to the schematic diagrams. When detailing the embodiments of this invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not adhering to the usual scale. Furthermore, the schematic diagrams are merely examples and should not be construed as limiting the scope of protection of this invention. In actual fabrication, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0031] Furthermore, in the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used solely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In addition, the terms "first," "second," or "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0032] Unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" in this invention should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; similarly, they can refer to mechanical connections, electrical connections, or direct connections, or indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0033] Example 1

[0034] Reference Figures 1-6 As an embodiment of the present invention, a flexible switching method for real-world faults in a distribution network is provided, comprising:

[0035] S1: Set n fault points and obtain fault simulation requirements.

[0036] Furthermore, the fault access of the real cable line is achieved by using a cable branch box connection method. The cable line is led out from the outgoing bay of the 10kV ring network cabinet and connected to a cable branch box with one inlet and two outlets. Then, the outgoing bay of the cable branch box is connected to a multi-point fault access switching device.

[0037] The multi-point fault access switching device is used to connect the fault access point and the fault access bus, and mainly consists of high-voltage contactors. To adapt to the 10kV voltage level distribution network real-world test field, the high-voltage contactors adopt a rated operating voltage of 12kV. Each multi-point fault access switching device uses 3 high-voltage contactors to realize the fault access of the three-phase lines A, B, and C.

[0038] The high-voltage contactor of the multi-point fault access switching device can be remotely controlled by the controller for opening and closing. Flexible switching of fault access points can be achieved directly within the management software of the prototype platform. The working principle is as follows: Figure 4 As shown.

[0039] It is important to know that the fault access bus is used to connect various fault access points and fault simulation devices, and to simulate multi-point faults.

[0040] The fault access bus consists of two lines, each connecting half the total number of fault points. For example, if the total number of fault points (n) is 16, then each fault bus connects 8 fault points. The number of fault points can be selected as needed. This explanation focuses on 16 fault points and the specific implementation method of connecting two fault buses for better understanding of the invention. However, in practice, the method is not limited to 16 fault points. It can be used according to actual needs, such as 8, 4, or more than 18 fault points. The difference lies in the number of fault switching devices and the number of cables used to deploy them. The selection depends primarily on the size of the actual field distribution network, available funds and space, and the requirements of the tests being conducted.

[0041] Furthermore, such as Figure 5 As shown, two sets of pole-mounted circuit breakers are used to connect the fault access busbars. When pole-mounted switch 1 is closed and pole-mounted switch 2 is open, it is used to connect the short-circuit fault simulation device to the fault busbar 1; when pole-mounted switch 1 is open and pole-mounted switch 2 is closed, it is used to connect the short-circuit fault simulation device to the fault busbar 2; when pole-mounted switch 1 is open and pole-mounted switch 2 is open, it is used to disconnect the short-circuit fault simulation device.

[0042] S2: After matching the simulated requirements, obtain further actual requirements.

[0043] Before entering the fault simulation, the initial settings and historical trigger times are analyzed; the simulation requirements are obtained, and the simulation effects that can achieve the fault simulation and the corresponding trigger times are matched with the historical records based on the simulation requirements; through further selection based on actual needs, the recommended setting value of the trigger time is obtained.

[0044] It's important to understand that simulation requirements refer to the clear definition of the simulation's objectives and requirements before conducting a fault simulation. Specifically, this involves specifying which type or types of fault access to configure. Based on these requirements, relevant information is extracted from historical data to ensure a match between the simulation and actual requirements. Actual requirements, on the other hand, refer to the further selection and determination of requirements based on the simulation requirements. This also includes the requirement's defined timeframe (T) for controlling fault access within that timeframe.

[0045] Furthermore, information matching the fault effects in the historical records to the simulation requirements is retrieved, and the control effect and corresponding trigger time settings are output. These trigger times are then categorized among all those that meet the simulation requirements. Trigger times that can stably connect to the fault, stabilize circuit measurement data, and record stable measurement data are classified as Category 1, with the shortest trigger time selected as the recommended setting. Trigger times that can connect to the fault but cannot record stable measurement data are classified as Category 2, with the shortest trigger time selected as the recommended setting. A step size t is set for the fault switching strategy. n The step size for type I is t1, and the step size for type II is t2. If the actual requirement is to be able to stably connect to the fault, stabilize the circuit's measurement data, and record stable measurement data, and the recommended setting value for type I is greater than T, then the trigger time is adjusted by t1. If the actual requirement is only fault access and the recommended setting value for type II is greater than T, then the trigger time is adjusted by t2.

[0046] It's important to understand that step sizes t1 and t2 need to be set according to the requirements. If the simulation requires stable fault access and recording of stable measurement data, then this type of trigger time that meets the requirements is set as category one. If the actual requirement only requires fault access without recording stable measurement data, then this type of trigger time is set as category two. The settings for each parameter in these two categories may be different, so the step size for the overall time setting can only increase proportionally, not one unit at a time. For example, if the simulation requires stable fault access and recording of stable measurement data at standards of 12s, 20s, and 8s, then the adjusted step size should be (12+20+8) / N, where N is the set step frequency, representing the time processing coefficient. The different time setting requirements for the two categories result in different step sizes, both set based on the shortest trigger time to achieve the desired outcome.

[0047] S3: Generate a fault simulation triggering time strategy based on the actual needs.

[0048] Furthermore, based on the obtained recommended settings, if the recommended settings meet the actual requirements, the recommended settings for the trigger time are directly imported; if the recommended settings exceed the actual time limit T, the recommended settings for the trigger time are adjusted according to the actual requirements, using a preset adjustment step size t.n Adjust the recommended trigger time setting until it meets the actual time limit requirements; if the preset adjustment step size t is used... n If adjusting the recommended trigger time setting fails to precisely meet the actual time limit T, the output, after step size adjustment, will exceed Tt. n Furthermore, the fault access was executed as a set value that did not exceed the actual requirement T trigger time.

[0049] Fault simulation devices are used to simulate fault types in real-world power distribution network tests, and mainly include short-circuit fault simulation devices and single-phase grounding fault simulation devices.

[0050] The short-circuit fault simulation device is used to simulate two-phase and three-phase short-circuit faults in the distribution network; the single-phase ground fault simulation device is used to simulate A-phase ground fault, B-phase ground fault, and C-phase ground fault.

[0051] The fault simulation device uses a pole-mounted circuit breaker connected to the fault access bus. The pole-mounted circuit breaker is controlled by a control terminal, which can realize the access control of short-circuit fault simulation device and single-phase ground fault simulation device.

[0052] To simulate grounding faults of the same phase and different phases in the distribution network, two single-phase grounding fault simulation devices need to be configured, with each single-phase grounding fault connected to a fault access bus.

[0053] To conduct a simulation of a single-phase ground fault with the same phase, firstly, the management software of the full-scale test platform is used to disconnect the connecting switch of the fault access bus, i.e., disconnect pole-mounted switch 1 and pole-mounted switch 2; then, the control switch of the single-phase ground fault device for the fault access bus 1 is closed, and the control switch of the single-phase ground fault device for the fault access bus 2 is also closed; the fault point is set through the management software of the full-scale test platform, selecting one fault point from the eight fault points of the fault access bus 1 and setting the ground fault phase, and selecting one fault point from the eight fault points of the fault access bus 2 and setting the same ground fault phase; finally, the fault trigger time is set to realize the simulation of the same-phase ground fault. If different trigger times are set, the simulation of the same-phase ground fault at different times can be realized.

[0054] It should also be noted that when conducting simulations of single-phase grounding faults with different phases, firstly, the tie switches of the fault access bus are disconnected using the management software of the full-scale test platform, i.e., pole-mounted switch 1 and pole-mounted switch 2 are disconnected; then, the control switch of the single-phase grounding fault device for the fault access bus 1 is closed, and the control switch of the single-phase grounding fault device for the fault access bus 2 is also closed; the fault points are set through the management software of the full-scale test platform, selecting one fault point from the eight fault points of the fault access bus 1 and setting a grounding fault phase, and selecting one fault point from the eight fault points of the fault access bus 2 and setting a different grounding fault phase; finally, the fault trigger time is set to realize the simulation of the grounding fault with different phases. If different trigger times are set, the simulation of the grounding fault with different phases at different times can be realized.

[0055] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments described above. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory, magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory, magnetic variable memory, ferroelectric memory, phase change memory, graphene memory, etc. Volatile memory can include random access memory or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory or dynamic random access memory, etc. The databases involved in the embodiments provided in this application can include at least one of relational databases and non-relational databases. Non-relational databases can include blockchain-based distributed databases, etc., and are not limited thereto.

[0056] The processors involved in the various embodiments provided in this application may be general-purpose processors, central processing units, graphics processors, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited thereto.

[0057] Example 2

[0058] Reference Figure 7 This invention provides a flexible switching method for real-world faults in a distribution network. To verify the beneficial effects of this invention, scientific demonstration is conducted through economic benefit calculations and simulation experiments.

[0059] like Figure 7As shown, a flexible switching method for real-world faults in a distribution network mainly includes a fault simulation access point, a multi-point fault access switching device, a fault access bus, and a fault simulation device.

[0060] Eight fault points were selected from the cable lines of the 10kV full-scale test platform. Four fault points (E1, E2, E3, E4) were connected to fault bus 1, and the other four fault points (E5, E6, E7, E8) were connected to fault bus 2. Eight fault points were also selected from the overhead lines. Four fault points (E9, E10, E11, E12) were connected to fault bus 1, and the other four fault points (E13, E14, E15, E16) were connected to fault bus 2.

[0061] By adopting the above-mentioned fault point arrangement method, it is possible to simulate single-phase grounding faults of the same phase and different phases in cable lines or overhead lines, making the simulation of single-phase grounding faults more flexible.

[0062] Each fault point is connected to the fault access bus using a multi-point fault access switching device. The single-phase high-voltage AC contactor of the multi-point fault access switching device is a single-pole vacuum contactor, which is suitable for AC 50Hz distribution network, with a rated operating voltage of 12kV and a rated operating current of 630A, and can be remotely controlled for opening and closing.

[0063] There are two fault access buses. Fault bus 1 is used to connect eight multi-point fault access switching devices, single-phase ground fault simulation device 1 and its control switch 1, and short-circuit fault simulation device control switch 3. Fault bus 2 is used to connect eight multi-point fault access switching devices, single-phase ground fault simulation device 2 and its control switch 2, and short-circuit fault simulation device control switch 4.

[0064] The steps for conducting a two-phase short-circuit fault test at location E1 using this invention are as follows:

[0065] 1: All multi-point fault access switching devices and fault simulation device control switches are in the open state.

[0066] 2: Determine the short-circuit test plan, including fault parameters such as fault phase, fault location, fault transition resistance, and fault duration.

[0067] 3. According to the test plan, configure the parameters of the short-circuit fault simulation device in the real-world test platform management software.

[0068] 4: Change the high-voltage AC contactor of the multi-point fault access switching device corresponding to the E1 fault point from the open state to the closed state.

[0069] 5: Set the control switch 4 of the short-circuit fault simulation device from open to closed.

[0070] 6: Use the real-type test platform management software to start the short-circuit fault simulation device to trigger the fault, that is, to complete the short-circuit fault simulation at position E1.

[0071] The experimental steps for conducting simultaneous phase-A ground faults at locations E2 and E6 using this invention are as follows:

[0072] 1: All multi-point fault access switching devices and fault simulation device control switches are in the open state.

[0073] 2: Determine the ground fault test plan, including fault parameters such as fault phase, fault location, fault transition resistance, and fault duration.

[0074] 3: According to the test plan, configure the parameters of single-phase grounding fault simulation device 1 and single-phase grounding fault simulation device 2 in the real-type test platform management software, that is, single-phase grounding fault simulation device 1 and single-phase grounding fault simulation device 2 simulate single-phase grounding of phase A at the same time.

[0075] 4: Change the high-voltage AC contactor of the multi-point fault access switching device corresponding to fault points E2 and E6 from the open state to the closed state.

[0076] 5: Set the control switch 1 of the single-phase ground fault simulation device 1 and the control switch 2 of the single-phase ground fault simulation device 2 from the open state to the closed state.

[0077] 6: Use the real-type test platform management software to start the single-phase grounding fault simulation device to trigger the fault, that is, to complete the simulation of the same-name phase grounding fault at positions E2 and E6.

[0078] The experimental steps for conducting tests using this invention to detect successive A-phase ground faults and B-phase ground faults at locations E10 and E14 are as follows:

[0079] 1: All multi-point fault access switching devices and fault simulation device control switches are in the open state.

[0080] 2: Determine the ground fault test plan, including fault parameters such as fault phase, fault location, fault transition resistance, and fault duration.

[0081] 3: According to the test plan, configure the parameters of single-phase ground fault simulation device 1 and single-phase ground fault simulation device 2 in the real test platform management software. That is, single-phase ground fault simulation device 1 first simulates a phase A ground fault in E10, and 10 seconds later, single-phase ground fault simulation device 2 simulates a phase B single-phase ground fault in E14.

[0082] 4: Change the high-voltage AC contactor of the multi-point fault access switching device corresponding to fault points E10 and E14 from the open state to the closed state.

[0083] 5: Set the control switch 1 of the single-phase ground fault simulation device 1 and the control switch 2 of the single-phase ground fault simulation device 2 from the open state to the closed state.

[0084] 6: Use the real-type test platform management software to start the single-phase grounding fault simulation device to trigger the fault, that is, to complete the simulation of the opposite-named phase grounding fault at positions E10 and E14.

[0085] The flexible switching method for real-type faults of the present invention can realize flexible switching of real-type test fault points without the need for manual test wiring, thus improving the efficiency of setting the fault location. At the same time, the present invention can flexibly realize multi-point fault simulation, simulating single-phase grounding faults and short-circuit faults simultaneously, simulating grounding faults of the same phase and grounding faults of different phases, thus solving the problem that existing methods cannot simulate the simultaneous occurrence of multiple fault points.

[0086] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A flexible switching method for real-world faults in a distribution network, characterized in that, include: Set n fault points and obtain fault simulation requirements; After matching the simulated requirements, further actual requirements are obtained; A fault simulation triggering time strategy is generated based on the actual requirements; The n fault points are assigned to two fault access buses, each fault access bus is connected to half of the total number of fault points, and the two fault access buses are connected by a tie switch. At the same time, the two fault access buses are respectively connected to a corresponding single-phase grounding fault simulation device. When simulating single-phase grounding faults of the same or different phases according to the actual needs, the following controls are executed: Disconnect the connecting switch to isolate the two faulty access buses; The control switches of the single-phase ground fault simulation devices corresponding to the two fault access busbars are both controlled to be closed. Select one fault point from the fault points of each of the two fault access buses, and set the same or different grounding fault phases; By setting the triggering time strategy, the simultaneous or different times of grounding faults of the same or different phases on the two fault access buses can be simulated.

2. The flexible switching method for real-type faults in distribution networks as described in claim 1, characterized in that: The fault point includes a T-connection of the three-phase lines on the incoming side of the pole-mounted circuit breaker of a 10kV overhead power line pole to form a fault access point. The cable of the fault access point extends to the hardened ground under the power pole and connects to the multi-point fault access switching device.

3. The flexible switching method for real-type faults in distribution networks as described in claim 2, characterized in that: The fault point also includes a multi-point fault access switching device for connecting the fault access point and the fault access bus. Each multi-point fault access switching device uses three high-voltage contactors to realize the fault access of the three-phase lines A, B, and C.

4. The flexible switching method for real-type faults in distribution networks as described in claim 3, characterized in that: Two pole-mounted circuit breakers are used to connect the fault access busbars. When pole-mounted switch 1 is closed and pole-mounted switch 2 is open, the short-circuit fault simulation device is connected to the fault bus 1. When pole-mounted switch 1 is opened and pole-mounted switch 2 is closed, the short-circuit fault simulation device is connected to the fault bus 2. When pole-mounted switch 1 and pole-mounted switch 2 are tripped, the short-circuit fault simulation device will be disconnected.

5. The flexible switching method for real-type faults in distribution networks as described in claim 4, characterized in that: The fault control includes analyzing the trigger times of the initial settings and retrieved historical settings before entering the fault simulation. Obtain simulation requirements, match simulation effects that can achieve fault simulation and corresponding trigger times from historical records based on those requirements; and obtain recommended trigger time settings by further selecting based on actual needs. Based on the obtained recommended settings, if the recommended settings meet the actual needs, the recommended settings for the trigger time are directly imported. If the recommended setting value is greater than the actual required time limit T, then the recommended setting value of the trigger time will be adjusted according to the actual requirements, using a preset adjustment step size t. n Adjust the recommended setting for the trigger time until it meets the actual time limit requirements. If the preset adjustment step size t is used... n If adjusting the recommended trigger time setting fails to precisely meet the actual time limit T, the output, after step size adjustment, will exceed Tt. n Furthermore, the fault access was executed as a set value that did not exceed the actual requirement T trigger time.

6. The flexible switching method for real-type faults in distribution networks as described in claim 5, characterized in that: The requirements include retrieving information from historical records that matches the fault effects of the simulation requirements, outputting the control effects and corresponding trigger times, and classifying all trigger times that meet the simulation requirements. The trigger time that enables stable fault access, stable circuit measurement data, and stable data recording is defined as Category 1, and the shortest trigger time is selected as the recommended setting value for Category 1. The trigger time that enables fault access but cannot record stable measurement data is defined as Category 2, and the shortest trigger time is selected as the recommended setting value for Category 2. The step size t is set for the fault switching strategy. n The step size for one type is t1, and the step size for the other type is t2. If the actual requirement is to be able to stably connect to the fault, stabilize the circuit's measurement data, and record stable measurement data, and if a recommended setting value is greater than T, then the trigger time is adjusted by t1. If the actual requirement is only fault access and the second recommended setting value is greater than T, then the trigger time is adjusted by t2.

7. A flexible switching system for real-world faults in a distribution network, employing the method described in any one of claims 1-6, characterized in that: The requirement acquisition unit acquires simulated requirements for flexible fault switching and transmits these requirements to the requirement analysis unit. The requirements analysis unit generates a trigger time setting value based on the requirements, and generates a fault switching instruction based on the setting value. The fault access switching unit performs fault access switching according to the fault switching command.

8. A computer device, comprising: Memory and processor; The memory stores a computer program, characterized in that: when the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

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