Grounding protection method, device and electronic equipment for traction circuit

Abstract

Embodiments of the present application provide a traction circuit grounding protection method, device and electronic equipment, the method comprising: obtaining a main current signal of a main circuit in a traction circuit detected by a first detection module; obtaining a leakage current signal of a ground wire in the traction circuit detected by a second detection module; in the case that the main current signal decreases at a first rate and the leakage current signal increases at a second rate, determining that there is a grounding fault, and outputting a warning signal; performing frequency spectrum analysis on the main current signal and the leakage current, determining a to-be-tested frequency spectrum feature of the main current signal and a to-be-tested frequency spectrum feature of the leakage current; comparing the to-be-tested frequency spectrum feature of the main current signal and the to-be-tested frequency spectrum feature of the leakage current with a reference feature of the main current signal and a reference feature of the leakage current under a preset normal working condition in a preset sliding window, and determining a grounding fault type.

Description

Technical Field

[0001] This application relates to the field of electrical safety protection technology, and in particular to grounding protection methods, devices and electronic equipment for traction circuits. Background Technology

[0002] Traction circuits are required in scenarios such as rail transit, electric locomotives, and substations. As the core link of power transmission, the insulation status of the traction circuit is directly related to equipment safety and personnel safety.

[0003] If a grounding fault occurs in the traction circuit and cannot be accurately identified and isolated, it can easily lead to electric arcs, fires, or even system failure. Therefore, an effective grounding protection device is urgently needed. Summary of the Invention

[0004] The purpose of this application is to provide a grounding protection method, apparatus, and electronic device for traction circuits, wherein the grounding protection method for traction circuits can provide effective grounding protection for traction circuits.

[0005] To solve the above-mentioned technical problems, the embodiments of this application are implemented through the following aspects.

[0006] In a first aspect, embodiments of this application provide a grounding protection method for a traction circuit. The method includes: acquiring a main current signal of the main circuit in the traction circuit detected by a first detection module, and acquiring a leakage current signal of the ground wire in the traction circuit detected by a second detection module; determining the existence of a grounding fault when the main current signal decreases at a first rate and the leakage current signal increases at a second rate, and outputting a warning signal; performing spectral analysis on the main current signal and the leakage current to determine the spectral characteristics to be measured of the main current signal and the leakage current; comparing the spectral characteristics to be measured of the main current signal and the leakage current signal with the reference characteristics of the main current signal and the leakage current signal under normal operating conditions in a preset sliding window to determine the type of grounding fault.

[0007] Secondly, embodiments of this application provide a grounding protection device for a traction circuit. The device includes: an acquisition module, used to acquire the main current signal of the main circuit in the traction circuit detected by a first detection module, and to acquire the leakage current signal of the ground wire in the traction circuit detected by a second detection module; an output module, used to determine the existence of a grounding fault and output a warning signal when the main current signal decreases at a first rate and the leakage current signal increases at a second rate; an analysis module, used to perform spectral analysis on the main current signal and the leakage current to determine the measured spectral characteristics of the main current signal and the leakage current; and a determination module, used to compare the measured spectral characteristics of the main current signal and the leakage current signal with the pre-stored reference characteristics of the main current signal and the leakage current signal under normal operating conditions in a preset sliding window to determine the type of grounding fault.

[0008] Thirdly, embodiments of this application provide an electronic device, including: a memory, a processor, and computer-executable instructions stored in the memory and executable on the processor, wherein the computer-executable instructions, when executed by the processor, implement the steps of the method described in the first aspect. Fourthly, embodiments of this application provide a computer-readable storage medium for storing computer-executable instructions that, when executed by a processor, implement the steps of the method described in the first aspect. In this embodiment of the application, a grounding protection method for a traction circuit includes: acquiring a main current signal of the main circuit in the traction circuit detected by a first detection module; acquiring a leakage current signal of the ground wire in the traction circuit detected by a second detection module; determining the existence of a grounding fault and outputting a warning signal when the main current signal decreases at a first rate and the leakage current signal increases at a second rate; performing spectral analysis on the main current signal and the leakage current to determine the measured spectral characteristics of the main current signal and the leakage current; comparing the measured spectral characteristics of the main current signal and the leakage current with preset reference characteristics of the main current signal and the leakage current signal under normal operating conditions in a preset sliding window to determine the grounding fault type. Therefore, in this embodiment of the application, the main current signal of the main circuit and the leakage current signal of the ground wire in the traction circuit can be obtained. When it is initially determined that there is a ground fault, the spectrum of the main current signal and the leakage current signal is analyzed to obtain the spectrum characteristics to be measured. Then, it is compared with the preset reference characteristics of the main current signal and the reference characteristics of the leakage current signal under normal operating conditions to determine the ground fault type. In this way, the ground fault type can be accurately identified so that different strategies can be adopted for different fault types to achieve effective grounding protection for the traction circuit. Attached Figure Description

[0009] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0010] Figure 1 This illustration shows a schematic flowchart of a grounding protection method provided in an embodiment of this application; Figure 2 This illustration shows another schematic flowchart of the grounding protection method provided in an embodiment of this application; Figure 3 This illustration shows a structural schematic diagram of a grounding protection device provided in an embodiment of this application; Figure 4 A schematic diagram of the hardware structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0011] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.

[0012] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0013] Traction circuits are required in scenarios such as rail transit, electric locomotives, and substations. As the core link of power transmission, the insulation status of the traction circuit is directly related to equipment safety and personnel safety.

[0014] If a grounding fault occurs in the traction circuit and cannot be accurately identified and isolated, it can easily lead to electric arcs, fires, or even system failure. Therefore, an effective grounding protection device is urgently needed.

[0015] This application provides a grounding protection method for traction circuits that solves the above-mentioned technical problems. Figure 1 This diagram illustrates a flow chart of a grounding protection method for a traction circuit provided in an embodiment of this application. This method can be executed by a processor or by an electronic device, such as a terminal device or a server device. The processor can be a high-performance MCU, a digital signal processor (such as a dual-core DSP), or an FPGA (Field-Programmable Gate Array), an ARM Cortex-M7 microcontroller, or a RISC-V architecture embedded chip. In other words, the method can be executed by the software or hardware of a server, terminal device, or server device equipped with a processor. Servers include, but are not limited to, single servers, server clusters, cloud servers, or cloud server clusters. Figure 1 As shown, the method may include the following steps.

[0016] Step S102: Obtain the main current signal of the main circuit in the traction circuit detected by the first detection module, and obtain the leakage current signal of the ground wire in the traction circuit detected by the second detection module.

[0017] In order to improve the real-time performance of grounding protection, the main current signal of the main circuit and the leakage current signal of the ground wire can be acquired in real time.

[0018] Step S104: When the main current signal decreases at a first rate and the leakage current signal increases at a second rate, a ground fault is determined to exist, and a warning signal is output.

[0019] The first and second rates can be set according to actual needs. For example, they can be set based on manual experience, or determined by the maximum rate of change of the main current signal under normal operating conditions, and the maximum rate of change of the leakage current signal to determine the second rate. For example, the first rate can be determined by two, three, or four times the maximum rate of change of the main current signal under normal operating conditions, and the second rate can be determined by two, three, or four times the maximum rate of change of the leakage current signal under normal operating conditions. When the main current signal decreases at the first rate and the leakage current signal increases at the second rate, it indicates that the main current value is decreasing rapidly and the leakage current value is increasing rapidly. At this time, a ground fault can be preliminarily determined, and therefore a warning signal can be output.

[0020] In one possible implementation, once a ground fault is detected, the alarm output unit can be controlled to issue an alarm. For example, when a ground fault is detected, the alarm output unit closes the solid-state relay contacts, driving an external audible and visual alarm or linking it to the train control system to perform protective actions.

[0021] Step S106: Perform spectral analysis on the main current signal and the leakage current to determine the spectral characteristics of the main current signal and the leakage current. In one possible implementation, the spectral analysis may be FFT spectral analysis, or it may be other analysis methods.

[0022] Step S108: The measured spectral characteristics of the main current signal and the measured spectral characteristics of the leakage current signal are analyzed and compared with the pre-stored reference characteristics of the main current signal and the leakage current signal under normal operating conditions within a preset sliding window to determine the ground fault type. The ground fault type is determined based on the difference between the measured spectral characteristics and the reference characteristics.

[0023] By using a preset sliding window, the main current signal and leakage current signal acquired in real time can be analyzed and the ground fault type can be determined in a timely manner, improving the timeliness of the grounding protection method. In this embodiment, the window length and sliding step size of the preset sliding window can be set as needed. The smaller the window length and sliding step size, the higher the real-time performance and the easier it is to continuously capture transient fluctuations. Of course, the computational load is also larger. In one embodiment, the window length can be 1s, 6s, 10s, 15s, or 20s, etc., and the sliding step size can be 0.5s, 1s, 2s, 3s, 4s, or 5s, etc. Of course, in some embodiments, a sliding window can be omitted, and a regular time window can be used instead.

[0024] The reference characteristics of the main current signal and the reference characteristics of the leakage current signal under normal operating conditions can be pre-stored in the storage unit, and the reference characteristics of the main current signal and the reference characteristics of the leakage current signal can be determined according to multiple sets (100 sets or 200 sets) of traction circuits under normal operating conditions.

[0025] Among them, the reference characteristics of the main current signal and the reference characteristics of the leakage current signal under normal operating conditions can be pre-stored in the ground fault mode library.

[0026] In this embodiment, the main current signal of the main circuit and the leakage current signal of the ground wire in the traction circuit can be acquired. When a ground fault is initially determined, the main current signal and the leakage current signal are subjected to spectrum analysis to obtain the spectrum characteristics to be measured. Then, they are compared with the preset reference characteristics of the main current signal and the leakage current signal under normal operating conditions to determine the ground fault type. In this way, the ground fault type can be identified in a timely and accurate manner, so that different strategies can be adopted for different fault types to achieve effective grounding protection for the traction circuit.

[0027] In one implementation, before performing spectral analysis on the main current signal and the leakage current, the main current signal of the main circuit and the leakage current signal of the ground wire can be converted from analog to digital, that is, the analog signal form can be converted into the digital signal form.

[0028] In this embodiment, the spectral characteristics to be measured may include: the amplitude of the spectral spectrum to be measured and the harmonic components to be measured; of course, other characteristics may also be included, such as the DC component to be measured. The reference characteristics may include: the reference spectral amplitude and the reference harmonic components; of course, other characteristics may also be included, such as the reference DC component.

[0029] In this embodiment of the application, step S108 may include the following steps A1 and / or A2.

[0030] In step A1, the ground fault type is determined to be high-resistance grounding if at least one of the following conditions A11 and A12 exists.

[0031] Case A11: In the main circuit current signal, the amplitude of the measured spectrum is greater than the amplitude of the reference spectrum, and the difference between the two is greater than a first threshold; in the leakage current signal, the amplitude of the measured spectrum is less than the amplitude of the reference spectrum, and the difference between the two is greater than a second threshold. If, in the main circuit current signal, the amplitude of the measured spectrum increases compared to the amplitude of the reference spectrum, and the difference or ratio of the increase is greater than the first threshold; or in the leakage current signal, the amplitude of the measured spectrum decreases compared to the amplitude of the reference spectrum, and the difference or ratio of the decrease is greater than the second threshold, a high-resistance grounding fault is considered to exist.

[0032] Case A12: In the main circuit current signal, the harmonic component to be measured is greater than the reference harmonic component, and the difference between the two is greater than the third threshold; in the leakage current signal, the harmonic component to be measured is greater than the reference harmonic component, and the harmonic component to be measured in the main current signal corresponds to the harmonic component to be measured in the leakage current signal. If, in the main circuit current signal, the harmonic component to be measured increases relative to the reference harmonic component, and the difference or ratio of this increase is greater than the third threshold, and in the leakage current signal, the harmonic component to be measured is greater than the reference harmonic component, and there is a corresponding relationship between the harmonic components to be measured in the main current signal and the leakage current signal, a high-resistance grounding fault is considered to exist.

[0033] In step A2, the ground fault type is determined to be metallic ground if at least one of the following conditions A21 and A22 exists.

[0034] Case A21: When the measured spectral amplitude of the main current signal decreases at a third rate, and the measured spectral amplitude of the leakage current signal increases at a fourth rate; the measured spectral amplitude of the main current signal is less than the reference spectral amplitude, and the difference between the two is greater than a fourth threshold; the measured spectral amplitude of the leakage current signal is greater than the reference spectral amplitude, and the difference between the two is greater than a fifth threshold; the third rate is greater than the first rate, and the fourth rate is greater than the second rate. Wherein, the third rate can be greater than the first rate, the fourth rate can be greater than the second rate, the fourth threshold is greater than the first threshold, and the fifth threshold is greater than the second threshold. In this case, the measured spectral amplitude of the main current signal decreases rapidly and significantly, while the measured spectral amplitude of the leakage current signal increases rapidly and significantly, indicating a metallic grounding fault.

[0035] Case A22: The difference between the measured harmonic component of the main current signal and the reference harmonic component is less than the sixth threshold; the measured harmonic component of the leakage current signal is greater than the reference harmonic component, and the difference between the two is greater than the seventh threshold; the measured harmonic component of the main current signal corresponds to the measured harmonic component of the leakage current signal; and the sixth threshold is less than the third threshold. Specifically, the difference between the measured harmonic component of the main current signal and the reference harmonic component being less than the sixth threshold indicates that their harmonic contents are similar, and the sixth threshold can be 0 or close to 0. In the leakage current signal, relative to the reference harmonic component, the measured harmonic component increases by more than the seventh threshold, and the measured harmonic component of the main current signal corresponds to the measured harmonic component of the leakage current signal. In this case, the fault type can be considered metallic grounding.

[0036] In one implementation, different fault types can trigger different levels of early warning actions, including but not limited to: Level 1 early warning, Level 2 alarm, and Level 3 tripping.

[0037] In one implementation, the thresholds described above can be non-negative numbers. In strict cases, each threshold can be 0 or close to 0; in other cases (such as in situations with high noise levels), each threshold can be set to a larger number to avoid false faults.

[0038] In this embodiment, the amplitude of the spectrum to be tested is not only judged based on the difference between its amplitude and the reference spectrum amplitude, but also combined with its rate of change to comprehensively judge the fault type. Thus, the fault type can be determined more accurately.

[0039] In this embodiment, the first detection module may include a first signal acquisition unit, a first filtering unit, and a first amplification unit. The first signal acquisition unit acquires the signal of the position to be measured in the main circuit, and the signal of the position to be measured in the main circuit passes through the first filtering unit and the first amplification unit in sequence to obtain the main current signal of the main circuit.

[0040] In this embodiment of the application, the second detection module includes a second signal acquisition unit, a second filtering unit, and a second amplification unit; the second signal acquisition unit acquires the signal of the ground wire at the test position, and the signal of the ground wire at the test position passes through the second filtering unit and the second amplification unit in sequence to obtain the leakage current signal of the ground wire.

[0041] To compensate for the effects of temperature and electromagnetic noise changes on the main current signal of the main circuit and the leakage current signal of the ground wire, and to accurately perform grounding protection, the grounding protection method in this application further includes: adjusting the equivalent capacitance value of the capacitor in the first filter unit and / or adjusting the resistance value of the digital potentiometer in the second amplification unit according to the changes in temperature and electromagnetic noise. This allows for dynamic adjustment of the filter cutoff frequency and amplification gain, compensating for the effects of temperature and electromagnetic noise changes on the main current signal of the main circuit and the leakage current signal of the ground wire, thereby improving environmental adaptability and increasing the accuracy of grounding fault diagnosis.

[0042] Figure 2 This diagram illustrates a flow chart of a grounding protection method for a traction circuit provided in an embodiment of this application. This method can be executed by a processor or by an electronic device, such as a terminal device or a server device. Figure 2 As shown, the method may include the following steps.

[0043] Step S200: Adjust the equivalent capacitance of the capacitor in the first filter unit of the first detection module and / or adjust the resistance of the digital potentiometer in the second amplification unit of the second detection module according to changes in temperature and electromagnetic noise. This is to accurately compensate for the effects of temperature and electromagnetic noise changes on the main current signal and ground leakage current signal of the main circuit.

[0044] Step S202: Obtain the main current signal of the main circuit in the traction circuit detected by the first detection module, and obtain the leakage current signal of the ground wire in the traction circuit detected by the second detection module.

[0045] Step S204: When the main current signal decreases at a first rate and the leakage current signal increases at a second rate, a ground fault is determined to exist, and a warning signal is output.

[0046] Step S206: Perform spectral analysis on the main current signal and the leakage current to determine the spectral characteristics of the main current signal and the spectral characteristics of the leakage current.

[0047] Step S208: The measured spectral characteristics of the main current signal and the measured spectral characteristics of the leakage current signal are analyzed and compared with the pre-stored reference characteristics of the main current signal and the leakage current signal under normal operating conditions in a preset sliding window to determine the ground fault type.

[0048] In this embodiment, the impact of the environment can be reduced, and the grounding fault type can be identified in a timely and accurate manner, so that different strategies can be adopted for different fault types in the future to achieve effective grounding protection for the traction circuit.

[0049] Step 200 above may include the following steps: Step B1: Obtain real-time environmental data collected by the environmental monitoring unit, which includes a temperature sensor and / or a noise monitoring circuit.

[0050] Among them, the temperature sensor can be attached to the inner wall of the traction circuit housing, and the noise detection circuit can pick up the ambient electromagnetic noise through capacitive coupling.

[0051] Step B2: Based on the deviation between real-time environmental data and reference environmental data, control the equivalent capacitance value of the capacitor in the first filtering unit and the resistance value of the digital potentiometer in the second amplification unit.

[0052] The reference environmental data is ideal environmental data. Since there is a deviation between the real-time environmental data and the reference environmental data, a PID algorithm can be used to output a control quantity based on the deviation between the real-time environmental data and the reference environmental data. The equivalent capacitance of the capacitor in the first filter unit and the resistance of the digital potentiometer in the second amplification unit are adjusted according to the control quantity, thereby forming a closed-loop adaptive adjustment circuit.

[0053] The equivalent capacitance of the capacitor in the first filter unit and the resistance of the digital potentiometer in the second amplification unit can be precisely adjusted in the form of PWM.

[0054] In one possible implementation, the first signal acquisition unit can be a Hall effect sensor, installed on the surface of the main circuit conductor of the traction circuit, and non-contactly sensing the main circuit current through magnetic coupling; the first filtering unit can be an RC low-pass filter circuit, consisting of a resistor and a capacitor connected in series and then in parallel in the signal path, with one end of the capacitor grounded to filter out high-frequency electromagnetic interference; the first amplification unit can be an operational amplifier chip, with its non-inverting input connected to the filter output, and its inverting input forming a negative feedback loop with the output through an adjustable feedback resistor to achieve signal gain adjustment, the gain value of which can be dynamically adjusted by external control.

[0055] In one possible implementation, the second signal acquisition unit can employ a zero-flux current transformer, installed around the ground wire, to acquire weak leakage current through the principle of electromagnetic induction; the second filtering unit can be an LC bandpass filter circuit, consisting of an inductor and a capacitor connected in series and then in parallel to the signal path, with the two ends of the capacitor connected to the signal path and the ground wire respectively, to extract effective fault characteristic signals in a specific frequency band (e.g., 50–500 Hz); the second amplification unit can be an instrumentation amplifier chip, with its gain control pin connected to a digital potentiometer, which can achieve automatic gain control (AGC) according to the signal strength, ensuring that weak signals are not distorted and strong signals are not saturated.

[0056] In one possible implementation, the analog-to-digital converter acquires the main current signal of the main circuit and the leakage current signal of the ground wire through the SPI interface, and converts them into high-precision digital signals for accurate spectrum analysis.

[0057] In one possible implementation, in the aforementioned dual-core DSP, one core executes the Fast Fourier Transform (FFT) algorithm to perform spectral analysis on the signal and extract harmonics, DC components, and characteristic frequency components, while the other core runs a fault feature matching algorithm to compare with a pre-stored ground fault mode library.

[0058] Figure 3 The diagram shows the structure of a grounding protection device provided in an embodiment of this application. The device 100 may include: an acquisition module 110, an output module 120, an analysis module 130, and a determination module 140.

[0059] The acquisition module 110 is used to acquire the main current signal of the main circuit in the traction circuit detected by the first detection module, and to acquire the leakage current signal of the ground wire in the traction circuit detected by the second detection module.

[0060] The output module 120 is used to determine the existence of a ground fault and output a warning signal when the main current signal decreases at a first rate and the leakage current signal increases at a second rate.

[0061] Analysis module 130 is used to perform spectrum analysis on the main current signal and the leakage current to determine the spectrum characteristics to be measured of the main current signal and the spectrum characteristics to be measured of the leakage current.

[0062] The determination module 140 is used to compare the test spectrum characteristics of the main current signal and the test spectrum characteristics of the leakage current signal with the pre-stored reference characteristics of the main current signal and the leakage current signal under normal operating conditions in a preset sliding window to determine the ground fault type.

[0063] The measured spectral features include: the measured spectral amplitude and the measured harmonic components; the reference features include: the reference spectral amplitude and the reference harmonic components.

[0064] In one embodiment, the device 100 is further configured to determine that the ground fault type is a high-resistance ground fault in at least one of the following situations: In the main current signal, the amplitude of the spectrum to be measured is greater than the amplitude of the reference spectrum, and the difference between the two is greater than a first threshold. In the leakage current signal, the amplitude of the spectrum to be measured is less than the amplitude of the reference spectrum, and the difference between the two is greater than a second threshold. In the main current signal, the harmonic component to be measured is greater than the reference harmonic component, and the difference between the two is greater than the third threshold. In the leakage current signal, the harmonic component to be measured is greater than the reference harmonic component, and the harmonic component to be measured in the main current signal corresponds to the harmonic component to be measured in the leakage current signal.

[0065] In one embodiment, the device 100 is further configured to determine that the ground fault type is metallic grounding when at least one of the following conditions exists: When the measured spectral amplitude of the main current signal decreases at a third rate, and the measured spectral amplitude of the leakage current signal increases at a fourth rate, the measured spectral amplitude of the main current signal is less than the reference spectral amplitude, and the difference between the two is greater than a fourth threshold, and the measured spectral amplitude of the leakage current signal is greater than the reference spectral amplitude, and the difference between the two is greater than a fifth threshold; the third rate is greater than the first rate, the fourth rate is greater than the second rate, the fourth threshold is greater than the first threshold, and the fifth threshold is greater than the second threshold; The difference between the measured harmonic component of the main current signal and the reference harmonic component is less than the sixth threshold, the measured harmonic component of the leakage current signal is greater than the reference harmonic component, and the difference between the two is greater than the seventh threshold, and the measured harmonic component of the main current signal corresponds to the measured harmonic component of the leakage current signal, and the sixth threshold is less than the third threshold.

[0066] In one embodiment, the first detection module includes a first signal acquisition unit, a first filtering unit, and a first amplification unit; the first signal acquisition unit acquires the signal of the position to be measured in the main circuit, and the signal of the position to be measured in the main circuit passes through the first filtering unit and the first amplification unit in sequence to obtain the main current signal of the main circuit.

[0067] In one embodiment, the second detection module includes a second signal acquisition unit, a second filtering unit, and a second amplification unit; the second signal acquisition unit acquires the signal of the ground wire at the location to be tested, and the signal of the ground wire at the location to be tested passes through the second filtering unit and the second amplification unit in sequence to obtain the leakage current signal of the ground wire.

[0068] In one embodiment, the device 100 is further configured to: Adjust the equivalent capacitance of the capacitor in the first filter unit and / or adjust the resistance of the digital potentiometer in the second amplification unit according to changes in temperature and electromagnetic noise.

[0069] The device 100 provided in this application embodiment can execute the methods described in the preceding method embodiments and achieve the functions and beneficial effects of the methods described in the preceding method embodiments, which will not be repeated here.

[0070] Figure 4 The diagram illustrates the hardware structure of an electronic device implementing the embodiments of this application. Referring to the diagram, at the hardware level, the electronic device includes a processor and optionally, an internal bus, a network interface, and a memory. The memory may include RAM, such as high-speed random-access memory (RAM), or non-volatile memory, such as at least one disk storage device. Of course, the electronic device may also include other hardware required for other services.

[0071] The processor, network interface, and memory can be interconnected via an internal bus, which can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. This bus can be categorized as an address bus, data bus, control bus, etc. For ease of illustration, only a single bidirectional arrow is used in this diagram, but this does not imply that there is only one bus or one type of bus.

[0072] Memory is used to store programs. Specifically, programs may include program code, which includes computer operation instructions. Memory may include main memory and non-volatile memory, and provides instructions and data to the processor.

[0073] The processor reads the corresponding computer program from non-volatile memory into main memory and then executes it, forming a device at the logical level that locates the target user. The processor executes the program stored in memory and specifically performs the following: Figure 1-2 The methods disclosed in the embodiments shown achieve the functions and beneficial effects of the methods described in the preceding method embodiments, and will not be repeated here.

[0074] The above is as stated in this application. Figure 1-2 The methods disclosed in the illustrated embodiments can be applied to or implemented by a processor. The processor may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above methods can be completed by integrated logic circuits in the processor's hardware or by instructions in software form. The processor can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it can also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly embodied in the execution of a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software module can reside in a mature storage medium in the field, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory, and the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method.

[0075] The electronic device can also execute the methods described in the preceding method embodiments and achieve the functions and beneficial effects of the methods described in the preceding method embodiments, which will not be repeated here.

[0076] Of course, in addition to software implementation, the electronic device of this application does not exclude other implementation methods, such as logic devices or a combination of hardware and software, etc. In other words, the execution subject of the following processing flow is not limited to each logic unit, but can also be hardware or logic devices.

[0077] This application also proposes a computer-readable storage medium that stores one or more programs, which, when executed by an electronic device including multiple applications, cause the electronic device to perform... Figure 1-2 The methods disclosed in the embodiments shown achieve the functions and beneficial effects of the methods described in the preceding method embodiments, and will not be repeated here.

[0078] The computer-readable storage medium mentioned above includes read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk, etc.

[0079] Furthermore, embodiments of this application also provide a computer program product, the computer program product including a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, which, when executed by a computer, implement the following process: Figure 1-2 The methods disclosed in the embodiments shown achieve the functions and beneficial effects of the methods described in the preceding method embodiments, and will not be repeated here.

[0080] In summary, the above description is merely a preferred embodiment of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

[0081] The systems, devices, modules, or units described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer. Specifically, a computer can be, for example, a personal computer, laptop computer, cellular phone, camera phone, smartphone, personal digital assistant, media player, navigation device, email device, game console, tablet computer, wearable device, or any combination of these devices.

[0082] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, 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 magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0083] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0084] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

Claims

1. A grounding protection method for a traction circuit, characterized in that, The method includes: The main current signal of the main circuit in the traction circuit detected by the first detection module and the leakage current signal of the ground wire in the traction circuit detected by the second detection module are obtained. When the main current signal decreases at a first rate and the leakage current signal increases at a second rate, a ground fault is determined to exist, and a warning signal is output. Spectral analysis is performed on the main current signal and the leakage current to determine the measured spectral characteristics of the main current signal and the measured spectral characteristics of the leakage current. The test spectrum characteristics of the main current signal and the test spectrum characteristics of the leakage current signal are compared with the pre-stored reference characteristics of the main current signal and the leakage current signal under normal operating conditions in a preset sliding window to determine the ground fault type.

2. The grounding protection method according to claim 1, characterized in that, The measured spectral characteristics include: the measured spectral amplitude and the measured harmonic components; the reference characteristics include: the reference spectral amplitude and the reference harmonic components; The step of comparing the measured spectral characteristics of the main current signal and the measured spectral characteristics of the leakage current signal with preset reference characteristics of the main current signal and the leakage current signal under normal operating conditions within a preset sliding window includes: A ground fault is classified as a high-resistance ground fault if at least one of the following conditions is present: In the main current signal, the amplitude of the spectrum to be measured is greater than the amplitude of the reference spectrum, and the difference between the two is greater than a first threshold. In the leakage current signal, the amplitude of the spectrum to be measured is less than the amplitude of the reference spectrum, and the difference between the two is greater than a second threshold. In the main current signal, the harmonic component to be measured is greater than the reference harmonic component, and the difference between the two is greater than the third threshold; in the leakage current signal, the harmonic component to be measured is greater than the reference harmonic component, and the harmonic component to be measured in the main current signal corresponds to the harmonic component to be measured in the leakage current signal; and / or A ground fault is determined to be a metallic ground fault if at least one of the following conditions is present: When the measured spectral amplitude of the main current signal decreases at a third rate, and the measured spectral amplitude of the leakage current signal increases at a fourth rate, the measured spectral amplitude of the main current signal is less than the reference spectral amplitude, and the difference between the two is greater than a fourth threshold, and the measured spectral amplitude of the leakage current signal is greater than the reference spectral amplitude, and the difference between the two is greater than a fifth threshold; the third rate is greater than the first rate, the fourth rate is greater than the second rate, the fourth threshold is greater than the first threshold, and the fifth threshold is greater than the second threshold; The difference between the measured harmonic component of the main current signal and the reference harmonic component is less than the sixth threshold, the measured harmonic component of the leakage current signal is greater than the reference harmonic component, and the difference between the two is greater than the seventh threshold, and the measured harmonic component of the main current signal corresponds to the measured harmonic component of the leakage current signal, and the sixth threshold is less than the third threshold.

3. The grounding protection method according to claim 1, characterized in that, The first detection module includes a first signal acquisition unit, a first filtering unit, and a first amplification unit; the first signal acquisition unit acquires the signal of the position to be tested in the main circuit, and the signal of the position to be tested in the main circuit passes through the first filtering unit and the first amplification unit in sequence to obtain the main current signal of the main circuit; The second detection module includes a second signal acquisition unit, a second filtering unit, and a second amplification unit; the second signal acquisition unit acquires the signal of the ground wire at the test position, and the signal of the ground wire at the test position passes through the second filtering unit and the second amplification unit in sequence to obtain the leakage current signal of the ground wire.

4. The grounding protection method according to claim 3, characterized in that, The method further includes: Adjust the equivalent capacitance of the capacitor in the first filter unit and / or adjust the resistance of the digital potentiometer in the second amplification unit according to changes in temperature and electromagnetic noise.

5. A grounding protection device for a traction circuit, characterized in that, The device includes: The acquisition module is used to acquire the main current signal of the main circuit in the traction circuit detected by the first detection module, and to acquire the leakage current signal of the ground wire in the traction circuit detected by the second detection module. The output module is used to determine the existence of a ground fault and output a warning signal when the main current signal decreases at a first rate and the leakage current signal increases at a second rate. The analysis module is used to perform spectral analysis on the main current signal and the leakage current to determine the spectral characteristics to be measured of the main current signal and the spectral characteristics to be measured of the leakage current. The determination module is used to compare the measured spectral characteristics of the main current signal and the measured spectral characteristics of the leakage current signal with the pre-stored reference characteristics of the main current signal and the leakage current signal under normal operating conditions in a preset sliding window to determine the ground fault type.

6. The grounding protection device according to claim 5, characterized in that, The measured spectral characteristics include: the measured spectral amplitude and the measured harmonic components; the reference characteristics include: the reference spectral amplitude and the reference harmonic components; The step of comparing the measured spectral characteristics of the main current signal and the measured spectral characteristics of the leakage current signal with preset reference characteristics of the main current signal and the leakage current signal under normal operating conditions within a preset sliding window includes: A ground fault is classified as a high-resistance ground fault if at least one of the following conditions is present: In the main current signal, the amplitude of the spectrum to be measured is greater than the amplitude of the reference spectrum, and the difference between the two is greater than a first threshold. In the leakage current signal, the amplitude of the spectrum to be measured is less than the amplitude of the reference spectrum, and the difference between the two is greater than a second threshold. In the main current signal, the harmonic component to be measured is greater than the reference harmonic component, and the difference between the two is greater than the third threshold; in the leakage current signal, the harmonic component to be measured is greater than the reference harmonic component, and the harmonic component to be measured in the main current signal corresponds to the harmonic component to be measured in the leakage current signal; and / or A ground fault is determined to be a metallic ground fault if at least one of the following conditions is present: When the measured spectral amplitude of the main current signal decreases at a third rate, and the measured spectral amplitude of the leakage current signal increases at a fourth rate, the measured spectral amplitude of the main current signal is less than the reference spectral amplitude, and the difference between the two is greater than a fourth threshold, and the measured spectral amplitude of the leakage current signal is greater than the reference spectral amplitude, and the difference between the two is greater than a fifth threshold; the third rate is greater than the first rate, the fourth rate is greater than the second rate, the fourth threshold is greater than the first threshold, and the fifth threshold is greater than the second threshold; The difference between the measured harmonic component of the main current signal and the reference harmonic component is less than the sixth threshold, the measured harmonic component of the leakage current signal is greater than the reference harmonic component, and the difference between the two is greater than the seventh threshold, and the measured harmonic component of the main current signal corresponds to the measured harmonic component of the leakage current signal, and the sixth threshold is less than the third threshold.

7. The grounding protection device according to claim 5, characterized in that, The first detection module includes a first signal acquisition unit, a first filtering unit, and a first amplification unit; the first signal acquisition unit acquires the signal of the position to be tested in the main circuit, and the signal of the position to be tested in the main circuit passes through the first filtering unit and the first amplification unit in sequence to obtain the main current signal of the main circuit; The second detection module includes a second signal acquisition unit, a second filtering unit, and a second amplification unit; the second signal acquisition unit acquires the signal of the ground wire at the test position, and the signal of the ground wire at the test position passes through the second filtering unit and the second amplification unit in sequence to obtain the leakage current signal of the ground wire.

8. The grounding protection device according to claim 7, characterized in that, The device is also used for: Adjust the equivalent capacitance of the capacitor in the first filter unit and / or adjust the resistance of the digital potentiometer in the second amplification unit according to changes in temperature and electromagnetic noise.

9. An electronic device, comprising: processor; as well as A memory configured to store computer-executable instructions, which, when executed, use the processor to perform the steps of the grounding protection method according to any one of claims 1-4.

10. A computer-readable storage medium storing one or more programs, which, when executed by an electronic device including a plurality of applications, cause the electronic device to perform the steps of the grounding protection method according to any one of claims 1-4.

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