Fault location method and device for overhead line system of direct current traction power supply system

Abstract

The application provides a catenary fault location method and device of a direct-current traction power supply system. The system is implemented by two traction substations for bilateral power supply. In response to a catenary short-circuit fault, bilateral protection devices are triggered to act simultaneously, including: obtaining fault data generated when the bilateral protection devices of the rigid-flexible transition section act; obtaining multiple sets of fault data points at the same time by synchronizing the fault data; determining the relative position of the short-circuit fault point and the junction point of the rigid-flexible transition section according to the fault data points; and performing fault location based on a preset fault location algorithm according to the fault data, the short-circuit fault data points and the relative position of the junction point of the rigid-flexible transition section to obtain the catenary fault point position. The application fills the gap that the existing method cannot realize catenary fault location in the rigid-flexible transition section, realizes full-line fault location of the metro direct-current traction power supply system, and ensures safe and effective operation of the metro.

Description

Technical Field

[0001] This application belongs to the field of rail transit technology, and in particular relates to a method and device for determining the location of contact network faults in a DC traction power supply system. Background Technology

[0002] The DC traction power supply system is the "lifeline" for the safe operation of the subway. If a fault occurs in the contact network and cannot be quickly and accurately located and isolated, it will lead to a large-scale operation interruption and cause huge social and economic impacts.

[0003] Fault location technology is crucial for ensuring rapid self-healing of traction power supply systems and minimizing outage time. However, existing location methods primarily target sections with a single contact wire material. For the unique transition zone connecting rigid and flexible contact wires, existing methods cannot be used, creating a blind spot. The inability to accurately locate faults in this section significantly prolongs troubleshooting and recovery time, becoming a weak link in the overall system reliability. Summary of the Invention

[0004] In view of this, this application aims to propose a method and device for fault location in the contact network of a DC traction power supply system, so as to solve the problem of difficulty in fault location in the rigid-flexible transition section of DC traction power supply.

[0005] To achieve the above objectives, the technical solution of this application is implemented as follows: In a first aspect, this application provides a method for fault location in a DC traction power supply system, wherein the system is powered by two traction substations on both sides, and in response to a short-circuit fault in the contact network, both sides of the protection device are triggered to operate simultaneously. The method includes: Acquire fault data generated when the bilateral protection device of the rigid-flexible transition section of the system is activated, wherein the fault data includes feeder voltage and feeder current; By synchronizing the fault data, multiple sets of fault data points at the same time can be obtained. Determine the relative position of the short-circuit fault location and the boundary point of the rigid-flexible transition section based on the fault data points; Based on the relative positions of the fault data, the short-circuit fault data points, and the junction of the rigid-flexible transition section, and using a preset fault ranging algorithm, the location of the contact network fault point is obtained.

[0006] Secondly, based on the same inventive concept, this application also provides a contact network fault location device for a DC traction power supply system. The system is powered from two traction substations on both sides, and in response to a short-circuit fault in the contact network, both sides of the protection device are triggered to operate simultaneously, including: The data acquisition module is configured to acquire fault data generated when the bilateral protection device of the rigid-flexible transition section of the system is activated, wherein the fault data includes feeder voltage and feeder current. The data synchronization module is configured to obtain multiple sets of fault data points at the same time by synchronizing the fault data. The location determination module is configured to determine the relative position of the short-circuit fault occurrence point and the boundary point of the rigid-flexible transition section based on the fault data points. The fault location module is configured to perform fault location based on the relative positions of the fault data, the short-circuit fault data points, and the junction of the rigid-flexible transition section, and based on a preset fault location algorithm, so as to obtain the location of the contact network fault point.

[0007] Thirdly, based on the same inventive concept, this application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the method described in the first aspect.

[0008] Fourthly, based on the same inventive concept, this application also provides a non-transitory computer-readable storage medium, wherein the non-transitory computer-readable storage medium stores computer instructions for causing the computer to perform the method as described in the first aspect.

[0009] Compared with the prior art, the contact network fault location method and device for DC traction power supply system described in this application have the following advantages: The ranging method described in this application fills the gap in existing fault ranging methods that cannot measure the distance of the contact network in the rigid-flexible transition section, realizes fault ranging of the entire line of the subway DC traction power supply system, can quickly locate the fault point, and ensure the safe and efficient operation of the subway. Attached Figure Description

[0010] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is an electrical wiring diagram of the dual-side power supply method for the DC traction power supply system for urban rail transit described in the embodiments of this application; Figure 2 This is a flowchart of the contact network fault location method for the rigid-flexible transition section of the DC traction power supply system described in the embodiments of this application; Figure 3 This is a schematic diagram of a model where the short-circuit fault point is located to the left of the junction of the rigid and flexible contact network, as described in the embodiments of this application. Figure 4This is a schematic diagram of a model where the short-circuit fault point is located to the right of the junction of the rigid and flexible contact network, as described in the embodiments of this application. Figure 5 This is a schematic diagram of the contact network fault location device in the rigid-flexible transition section of the DC traction power supply system described in this application embodiment; Figure 6 This is a schematic diagram of the hardware structure of the electronic device described in an embodiment of this application. Detailed Implementation

[0011] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0012] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0013] As described in the background section above, the inability to accurately locate faults in the rigid-flexible transition section of the contact network in urban rail transit DC traction power supply systems significantly prolongs fault diagnosis and recovery time. Therefore, this embodiment establishes a dedicated fault location method for the rigid-flexible transition section of the contact network. This is not only a necessary technical step to improve the existing protection system but also an urgent requirement to ensure the safe operation of the metro network at high density. This method will effectively fill the gap in the existing fault location system, achieving "no blind spots" in the accurate location of power supply faults. It provides core technical support for building a more intelligent and robust metro power supply system and has significant practical implications for the sustainable development of rail transit.

[0014] The embodiments of this application are described in detail below with reference to the accompanying drawings.

[0015] Figure 1This is an electrical wiring diagram for a dual-supply DC traction power supply system for urban rail transit. In the DC traction power supply system's overhead contact line, each power supply section has two traction substations providing dual-supply, while the beginning and end of the supply line are single-supply. Each traction substation includes a DC feeder cabinet and a DC protection device. The DC protection device controls its respective DC feeder cabinet and collects feeder voltage and current. Each traction substation supplies power to the overhead contact line through its own DC feeder cabinet. Within one power supply section, one traction substation is referred to as the "local traction substation," and the other is called the "reciprocal traction substation," and vice versa.

[0016] The fault location method described in this embodiment is applied to the rigid-flexible transition contact network of a DC traction power supply system. In this contact network, the DC protection device of the double-sided traction substation periodically and continuously collects the telemetry data feeder voltage of the traction substation. Feeder current .

[0017] Please see Figure 2 As shown, this embodiment provides a method for fault location in a DC traction power supply system. The system is powered by two traction substations on both sides. In response to a short-circuit fault in the contact network, both protection devices are triggered to operate simultaneously. The method specifically includes the following steps: Step S101: Obtain the fault data generated when the system's rigid-flexible transition section bilateral protection device operates, including feeder voltage and feeder current.

[0018] Specifically, in this embodiment, when a short-circuit fault occurs in the subway DC traction power supply system, the protection devices in the system will act rapidly according to the pre-set protection logic. These devices may include circuit breakers, relays, and current sensors, which will monitor current and voltage waveforms to trigger actions when a fault occurs. The current and voltage data recorded by the devices include waveforms before, during, and after the fault to ensure a comprehensive record of the fault phenomenon.

[0019] Step S102: Synchronize the fault data to obtain multiple sets of fault data points at the same time.

[0020] Specifically, in this embodiment, the bilateral traction substations exchange the data recorded before, during, and after the fault through communication. The data synchronization method (which is a conventional technical means well known to those skilled in the art and is not considered an innovation of this application, so it will not be described in detail here) is used to synchronize the data and form multiple sets of bilateral fault data at the same time, including the feeder voltage and feeder current during the fault formation process of each substation.

[0021] Step S103: Determine the relative position of the short-circuit fault location and the junction of the rigid-flexible transition section based on the fault data points.

[0022] Specifically, in this embodiment, short-circuit faults can occur on the left and right sides of the junction of the rigid and flexible contact networks. The circuit structures differ at these two fault locations; therefore, it is necessary to first determine the relative position of the short-circuit fault location and the junction of the rigid and flexible contact networks. This embodiment uses the following judgment method for determination, which is explained in detail below: Using the boundary point of the rigid-flexible transition section as the dividing line, under the steady-state analysis of the overhead contact system, the relative position of the short-circuit fault occurrence point and the boundary point of the rigid-flexible transition section is determined according to the criterion formula, as follows: when At this time, the short-circuit fault occurs to the left of the junction of the rigid-flexible transition section; when At this time, the short-circuit fault occurs at the right side of the junction of the rigid-flexible transition section; when At this time, the short-circuit fault occurs at the junction of the rigid-flexible transition section; In the formula, , These represent the feeder voltage and feeder current of substation M, respectively. This represents the distance from substation M to boundary point J. This represents the resistivity of the contact network from substation M to boundary point J. , These represent the feeder voltage and feeder current of substation N, respectively. This represents the distance from substation N to boundary point J. This represents the resistivity of the contact network from substation N to boundary point J. This indicates the resistivity of the rail.

[0023] Step S104: Based on the relative positions of fault data, short-circuit fault data points and the junction of rigid and flexible transition sections, and based on a preset fault location algorithm, fault location is determined to obtain the location of the contact network fault point.

[0024] Specifically, in this embodiment, Figure 3 This is a transient model of a short-circuit fault in the contact network of the rigid-flexible transition section of a subway DC traction power supply system. The fault occurs to the left of the junction of the rigid and flexible contact networks, and the positive direction arrow of the current is marked. A detailed explanation and analysis are provided below. According to Kirchhoff's voltage and current laws, the following equation can be written for the current loop containing it: ; neglect ,have to ; Because the inductance between substation M and fault point F is Given that its inductance per unit length is The distance between substation M and fault point F is Then, according to the inductance calculation formula, we can obtain... ; Similarly, it can be concluded that Substituting each into the equation, we get: ; In the formula, This represents the distance between traction substation M and traction substation N. This represents the distance between substation M and fault point F. This represents the distance between substation N and fault point F. This represents the resistivity of the contact network from substation M to boundary point J. This represents the resistivity of the contact network from substation N to boundary point J. Indicates the resistivity of the rail. This represents the contact network resistance from substation M to fault point F. This represents the contact wire inductance from substation M to fault point F. This represents the rail resistance from substation M to fault point F. This represents the rail inductance from substation M to fault point F. This represents the inductance per unit length of the contact wire from substation M to boundary point J. This represents the inductance per unit length of the contact wire from substation N to boundary point J. This represents the inductance per unit length of the rail. This represents the rail resistance from substation N to fault point F. This represents the rail inductance from substation N to fault point F. This represents the contact wire resistance from substation N to boundary point J. This represents the resistance between the fault point F and the boundary point J. Indicates the transition resistance. This represents the contact wire inductance from substation N to junction point J.

[0025] Neglecting the effect of inductance on the circuit, we solve the steady-state equations and divide the two equations to obtain... ; Solving the equation yields the first distance measurement formula. This formula is used to determine the fault distance when the fault occurs to the left of the rigid-flexible junction point of the overhead contact line. The first distance measurement method is as follows: ; In the formula, This represents the distance between traction substation M and traction substation N. This represents the distance between substation M and fault point F. This represents the distance between substation N and fault point F.

[0026] Figure 4 This is a transient model of a short-circuit fault in the contact network of the rigid-flexible transition section of a subway DC traction power supply system. The fault occurs to the right of the junction point between the rigid and flexible contact networks, and the positive direction arrow of the current is indicated. A detailed explanation and analysis are provided below: According to Kirchhoff's voltage and current laws, the following equation can be written for the current loop containing it: ; neglect , ; Because the inductance between substation M and junction point J is Given that its inductance per unit length is The distance between substation M and boundary point J is Then, according to the inductance calculation formula, we can obtain... Similarly, it can be concluded that... Substituting each into the equation, we get: ; Neglecting the effect of inductance on the circuit, we solve the steady-state equations and divide the two equations to obtain... ; Solving the equation yields the second distance measurement formula, which is used to determine the fault distance when the fault occurs to the right of the rigid-flexible junction point of the overhead contact line. The second distance measurement formula is: .

[0027] It should be noted that in this embodiment, since the distance calculation formulas differ for the left and right sides of the boundary point where the fault occurs, it is necessary to determine whether the fault occurs on the left or right side of the boundary point at the beginning of the distance measurement. The determination method is as follows: When the fault happens to occur at the boundary point Substituting this into the distance measurement formula for the left side of the rigid-flexible junction of the overhead contact line, if transient effects are not considered, we can obtain: The formula for when the fault occurs at the boundary point is: .

[0028] If the fault occurs to the left of the intersection point Decrease Increase Increase If the value is reduced, the formula for when the fault occurs to the left of the boundary point is: ; If the fault occurs to the right of the intersection point Increase Decrease Decrease If the value increases, the formula for when the fault occurs to the right of the boundary point is: ; Therefore, it can be used as a basis for determining the location of the fault.

[0029] The transient equations can be discretized using a finite difference algorithm. Multiple sets of fault data acquired at different times after the fault are used to solve the finite difference equations, thereby calculating the fault ranging result. In practice, simulations and experiments have shown that the steady-state equations are sufficient to meet the ranging requirements.

[0030] The fault location method for the contact network of the rigid-flexible transition section of DC traction power supply described in this embodiment extracts fault data from historical records obtained from both substations, synchronizes the data, and then uses a contact network fault location algorithm suitable for rigid-flexible transition sections to calculate the fault location. This method can promptly and accurately detect and locate fault locations in the rigid-flexible transition section of the metro, making up for the lack of rigid-flexible transition section location function in the existing metro DC fault location function. This allows the metro DC fault location function to be fully covered in the metro DC traction power supply system, quickly locate fault points, ensure passenger safety, reduce the time to restore operation, improve operational efficiency, and reduce maintenance and repair costs.

[0031] It should be noted that the above description describes some embodiments of this application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in a different order than that shown in the above embodiments and still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0032] Based on the same inventive concept, and corresponding to the methods of any of the above embodiments, the embodiments of this application also provide a contact network fault location device for a DC traction power supply system.

[0033] like Figure 5 As shown, the contact network fault location device of the DC traction power supply system, wherein the system is powered by two traction substations on both sides, and in response to the occurrence of a contact network short-circuit fault, triggers the simultaneous operation of the two-sided protection devices, including: The data acquisition module 11 is configured to acquire fault data generated when the double-sided protection device of the rigid-flexible transition section of the system is activated, wherein the fault data includes feeder voltage and feeder current. The data synchronization module 12 is configured to obtain multiple sets of fault data points at the same time by synchronizing the fault data. The location determination module 13 is configured to determine the relative position of the short-circuit fault occurrence point and the boundary point of the rigid-flexible transition section based on the fault data points; The fault location module 14 is configured to perform fault location based on the relative positions of the fault data, the short-circuit fault data points, and the junction of the rigid-flexible transition section, and based on a preset fault location algorithm, so as to obtain the location of the contact network fault point.

[0034] For ease of description, the above apparatus is described in terms of its functions, divided into various modules. Of course, in implementing the embodiments of this application, the functions of each module can be implemented in one or more software and / or hardware.

[0035] The apparatus of the above embodiments is used to implement the corresponding method in any of the foregoing embodiments and has the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0036] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, embodiments of this application also provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the methods described in any of the above embodiments.

[0037] Figure 6 This embodiment illustrates a more specific hardware structure of an electronic device, which may include a processor 1010, a memory 1020, an input / output interface 1030, a communication interface 1040, and a bus 1050. The processor 1010, memory 1020, input / output interface 1030, and communication interface 1040 are interconnected internally via the bus 1050.

[0038] The processor 1010 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this specification.

[0039] The memory 1020 can be implemented in the form of ROM (Read Only Memory), RAM (Random Access Memory), static storage device, dynamic storage device, etc. The memory 1020 can store the operating system and other applications. When the technical solutions provided in the embodiments of this specification are implemented by software or firmware, the relevant program code is stored in the memory 1020 and is called and executed by the processor 1010.

[0040] The input / output interface 1030 is used to connect input / output modules to realize information input and output. The input / output modules can be configured as components in the device (not shown in the figure) or externally connected to the device to provide corresponding functions. Input devices may include keyboards, mice, touch screens, microphones, various sensors, etc., and output devices may include displays, speakers, vibrators, indicator lights, etc.

[0041] The communication interface 1040 is used to connect a communication module (not shown in the figure) to enable communication between this device and other devices. The communication module can communicate via wired means (such as USB, Ethernet cable, fiber optic cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.).

[0042] Bus 1050 includes a pathway for transmitting information between various components of the device, such as processor 1010, memory 1020, input / output interface 1030, and communication interface 1040.

[0043] It should be noted that although the above-described device only shows the processor 1010, memory 1020, input / output interface 1030, communication interface 1040, and bus 1050, in specific implementations, the device may also include other components necessary for normal operation. Furthermore, those skilled in the art will understand that the above-described device may only include the components necessary for implementing the embodiments of this specification, and not necessarily all the components shown in the figures.

[0044] The electronic devices described above are used to implement the corresponding methods in any of the foregoing embodiments and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0045] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, this application also provides a non-transitory computer-readable storage medium that stores computer instructions for causing the computer to perform the methods described in any of the above embodiments.

[0046] The computer-readable medium of this embodiment includes permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device.

[0047] The computer instructions stored in the storage medium of the above embodiments are used to cause the computer to perform the method described in any of the above embodiments, and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0048] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application (including the claims) is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in the details for the sake of brevity.

[0049] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications, and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may be used with the embodiments discussed.

[0050] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A method for determining contact network fault location in a DC traction power supply system, wherein the system is powered from two traction substations on both sides, and in response to a short-circuit fault in the contact network, both sides of the protection devices are triggered to operate simultaneously, characterized in that... The method includes: Acquire fault data generated when the bilateral protection device of the rigid-flexible transition section of the system is activated, wherein the fault data includes feeder voltage and feeder current; By synchronizing the fault data, multiple sets of fault data points at the same time can be obtained. Determine the relative position of the short-circuit fault location and the boundary point of the rigid-flexible transition section based on the fault data points; Based on the relative positions of the fault data, the short-circuit fault data points, and the junction of the rigid-flexible transition section, and using a preset fault ranging algorithm, the location of the contact network fault point is obtained.

2. The method according to claim 1, characterized in that, Using the boundary point of the rigid-flexible transition section as the dividing line, under the steady-state analysis of the overhead contact system, the relative position of the short-circuit fault occurrence point and the boundary point of the rigid-flexible transition section are determined according to the criterion formula, wherein the criterion formula is as follows: when At this time, the short-circuit fault occurs to the left of the junction of the rigid-flexible transition section; when At this time, the short-circuit fault occurs at the right side of the junction of the rigid-flexible transition section; when At this time, the short-circuit fault occurs at the junction of the rigid-flexible transition section; In the formula, , These represent the feeder voltage and feeder current of substation M, respectively. This represents the distance from substation M to boundary point J. This represents the resistivity of the contact network from substation M to boundary point J. , These represent the feeder voltage and feeder current on the N side of the substation, respectively. This represents the distance from substation N to boundary point J. This represents the resistivity of the contact network from substation N to boundary point J. This indicates the resistivity of the rail.

3. The method according to claim 2, characterized in that: The fault distance when the fault occurs to the left of the rigid-flexible junction point of the overhead contact line is determined by the first ranging formula, which is: ； In the formula, This represents the distance between traction substation M and traction substation N. This represents the distance between substation M and fault point F. This represents the distance between substation N and fault point F.

4. The method according to claim 2, characterized in that: The fault distance when the fault occurs to the right of the rigid-flexible junction point of the overhead contact line is determined by the second distance measurement formula, which is: ； In the formula, This represents the distance between traction substation M and traction substation N. This represents the distance between substation M and fault point F. This represents the distance between substation N and fault point F.

5. A contact network fault location device for a DC traction power supply system, wherein the system is powered from two traction substations on both sides, and in response to a short-circuit fault in the contact network, both sides of the protection device are triggered to operate simultaneously, characterized in that... include: The data acquisition module is configured to acquire fault data generated when the bilateral protection device of the rigid-flexible transition section of the system is activated, wherein the fault data includes feeder voltage and feeder current. The data synchronization module is configured to obtain multiple sets of fault data points at the same time by synchronizing the fault data. The location determination module is configured to determine the relative position of the short-circuit fault occurrence point and the boundary point of the rigid-flexible transition section based on the fault data points. The fault location module is configured to perform fault location based on the relative positions of the fault data, the short-circuit fault data points, and the junction of the rigid-flexible transition section, and based on a preset fault location algorithm, so as to obtain the location of the contact network fault point.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method as described in any one of claims 1-4.

7. A non-transitory computer-readable storage medium, characterized in that, in, The non-transitory computer-readable storage medium stores computer instructions for causing a computer to perform the method described in any one of claims 1-4.

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