Current increment protection method and device, storage medium and computer program

Abstract

The invention relates to a current increment protection method and device, a storage medium and a computer program, and the method comprises the steps: calculating the current increment of the feeder current of a traction substation at a current moment and the total harmonic content of a cycle time window at the current moment based on a sampling value sequence of the feeder current of the traction substation, wherein the current increment of the feeder current of the traction substation at the current moment is the current variation of the effective value of the fundamental component of the feeder current of the traction substation at the current moment relative to the effective value of the fundamental component of the previous cycle at the current moment; therefore, whether current increment protection is started or not is determined according to the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of the cycle time window at the current moment according to a preset current increment protection strategy, and the load and high-resistance grounding fault of the electric locomotive can be effectively identified. And the reliability and the sensitivity of current increment protection are improved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of electrified railway traction power supply, and in particular to a current increment protection method, device, equipment, storage medium and computer program. Background Art

[0002] The principle of current increment protection is that when a high-resistance fault occurs, the instantaneous increase in current is large, while the increase in current is small when the working condition of the electric locomotive changes. In order to avoid the formation of excitation surge current when the traction transformer on the electric locomotive is put back into operation after the electric locomotive is over-powered and split, a large excitation surge current may be greater than the setting value of the current increment protection and cause the protection to malfunction, so the second harmonic locking function is generally configured. On the lines where "AC-DC" electric locomotives operate, the current increment protection is also configured with a comprehensive harmonic suppression function based on the 2nd, 3rd, 5th, and 7th low-order harmonics. When the comprehensive harmonic content is high, the current increment protection action area is adaptively reduced to reduce the occurrence of malfunctions.

[0003] Since multiple locomotives may run on the same power supply arm, when a new locomotive is put into the traction transformer without load, the second harmonic content of the feeder current detected in the traction substation may be lower than the second harmonic blocking setting value, resulting in the failure of the second harmonic blocking function. With the large-scale use of "AC-DC-AC" locomotives on electrified railways, the comprehensive harmonics of the locomotive load current are getting smaller and smaller, and the comprehensive harmonic suppression function is gradually failing.

[0004] In view of the problem that the current incremental protection method cannot identify the high-resistance grounding fault of small current, the current incremental protection setting value is reduced in the existing technology, but the current incremental protection malfunction phenomenon occurs frequently due to the change of the working condition of the electric locomotive. Therefore, it is necessary to improve the current incremental protection method to improve the reliability and sensitivity of the current incremental protection, which plays an important role in ensuring the reliable operation of the traction power supply system. Summary of the invention

[0005] The present disclosure provides a current increment protection method, apparatus, device, storage medium and computer program to improve the reliability and sensitivity of current increment protection.

[0006] In a first aspect, the present disclosure provides a current increment protection method, comprising:

[0007] Obtaining a sampling value sequence of the feeder current of the traction substation;

[0008] Based on the sampling value sequence of the feeder current of the traction substation, the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of one cycle time window at the current moment are calculated, wherein the current increment of the feeder current of the traction substation at the current moment is the current change amount of the effective value of the fundamental component of the feeder current of the traction substation at the current moment relative to the effective value of the fundamental component of the previous cycle at the current moment;

[0009] Whether to start the current increment protection is determined according to the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of one cycle time window at the current moment according to the preset current increment protection strategy.

[0010] In some embodiments, the current increment protection strategy includes:

[0011] When the current increment of the feeder current of the traction substation at the current moment is greater than or equal to the preset current increment setting value, and the total harmonic content of the feeder current of the traction substation in one cycle time window at the current moment is greater than or equal to the preset total harmonic content blocking setting value, the current increment protection is blocked;

[0012] When the current increment of the feeder current of the traction substation at the current moment is greater than or equal to the preset current increment setting value, and the total harmonic content of the feeder current of the traction substation in one cycle time window at the current moment is less than the preset total harmonic content locking setting value for a duration that reaches the preset current increment protection setting delay value, a protection exit command is issued.

[0013] In some embodiments, when the electric traction power supply mode is a direct power supply mode, the feeder current of the traction substation is the feeder contact network current of the traction substation;

[0014] When the electric traction power supply mode is the AT power supply mode, the feeder current of the traction substation is the difference between the contact network current of the traction substation and the positive feeder current.

[0015] In some embodiments, the current increment protection setting value is a maximum current increment value when the operating condition of the power supply arm changes.

[0016] In some embodiments, the total harmonic content blocking setting value is a minimum total harmonic content value of the feeder current of the traction substation to avoid changes in the operating conditions of the power supply arm.

[0017] In some embodiments, calculating the current increment of the feeder current of the traction substation at the current moment based on the sampling value sequence of the feeder current of the traction substation includes:

[0018] Obtain a sampling value sequence of a cycle time window of the feeder current of the traction substation at the current moment;

[0019] Performing Fourier transformation on a sampling value sequence of a one-cycle time window of the feeder current of the traction substation at the current moment to obtain an effective value sequence of a fundamental component of a one-cycle time window of the feeder current of the traction substation at the current moment;

[0020] Based on the effective value sequence of the fundamental component of the feeder current of the traction substation in one cycle time window at the current moment and the current change of the effective value of the fundamental component of the feeder current of the traction substation in the previous cycle at the current moment, the current increment of the feeder current of the traction substation at the current moment is calculated.

[0021] In some embodiments, calculating the total harmonic content of the feeder current of the traction substation in one cycle time window at the current moment based on the sampling value sequence of the feeder current of the traction substation includes:

[0022] Reconstructing the effective value sequence of the fundamental component of the feeder current of the traction substation in one cycle time window at the current moment to obtain the sampling value sequence of the fundamental component of the feeder current of the traction substation in one cycle time window at the current moment;

[0023] Based on the fundamental component sampling value sequence of the feeder current of the traction substation in one cycle time window at the current moment and the sampling value sequence of the feeder current of the traction substation in one cycle time window at the current moment, the harmonic component sampling value sequence of the feeder current of the traction substation in one cycle time window at the current moment is calculated;

[0024] Based on the harmonic component sampling value sequence of the feeder current of the traction substation in one cycle time window at the current moment, calculate the total harmonic effective value of the feeder current of the traction substation in one cycle time window at the current moment;

[0025] Based on the total harmonic effective value of the feeder current of the traction substation in a cycle time window at the current moment, the total harmonic content of the feeder current of the traction substation in a cycle time window at the current moment is calculated.

[0026] In a second aspect, the present disclosure provides a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method described in the above aspect.

[0027] In a third aspect, the present disclosure provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the method described in the above aspects when executed by a processor.

[0028] In a fourth aspect, the present disclosure provides a computer program product, including a computer program / instructions, which implements the steps of the method described in the above aspects when the computer program is executed by a processor.

[0029] The present disclosure provides a current increment protection method, device, storage medium and computer program, which obtain the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of one cycle time window at the current moment by calculating based on the sampling value sequence of the feeder current of the traction substation; thereby determining whether to start the current increment protection according to the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of one cycle time window at the current moment according to a preset current increment protection strategy, which can effectively identify the load of the electric locomotive and the high-resistance grounding fault, so as to improve the reliability and sensitivity of the current increment protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present disclosure will be described in more detail below based on embodiments and with reference to the accompanying drawings:

[0031] Figure 1 A schematic diagram of a flow chart of a current increment protection method provided in an embodiment of the present disclosure;

[0032] Figure 2 A logic diagram of the current increment protection action with feeder current total harmonic blocking provided by an embodiment of the present disclosure;

[0033] Figure 3 A graph showing the original waveform of the feeder current containing the excitation inrush current and the effective value of the fundamental component provided by the embodiment of the present disclosure;

[0034] Figure 4 A waveform diagram of fundamental wave and harmonic wave separated from the original waveform of feeder current containing magnetizing inrush current provided by an embodiment of the present disclosure;

[0035] Figure 5 A curve diagram of total harmonic content and total harmonic content blocking setting value of feeder current containing magnetizing inrush current provided in an embodiment of the present disclosure;

[0036] Figure 6 A graph showing the original waveform of the feeder current with symmetrical magnetizing inrush current and the effective value of the fundamental component provided by the embodiment of the present disclosure;

[0037] Figure 7 A waveform diagram of fundamental and harmonic waves separated from the original waveform of the feeder current containing symmetrical excitation inrush current provided by an embodiment of the present disclosure;

[0038] Figure 8 A curve diagram of total harmonic content and total harmonic content blocking setting value of feeder current containing symmetrical excitation inrush current provided in an embodiment of the present disclosure;

[0039] Fig. 9 A graph showing the original waveform of the feeder current and the effective value of the fundamental component of the electric locomotive under acceleration conditions provided by an embodiment of the present disclosure;

[0040] Fig.10 A waveform diagram of fundamental wave and harmonic wave separated from the original waveform of feeder current of an electric locomotive accelerating condition provided by an embodiment of the present disclosure;

[0041] Fig.11 A curve diagram of total harmonic content of feeder current and total harmonic content blocking setting value for an electric locomotive accelerating condition provided by an embodiment of the present disclosure;

[0042] Fig.12 A graph showing the original waveform of the feeder current and the effective value of the fundamental component of a high-resistance grounding fault provided by an embodiment of the present disclosure;

[0043] Fig.13 A waveform diagram of fundamental wave and harmonic wave separated from the original waveform of feeder current of a high-resistance grounding fault provided by an embodiment of the present disclosure;

[0044] Fig.14 A curve diagram of the total harmonic content of the feeder current and the total harmonic content blocking setting value for a high-resistance grounding fault provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0045] In order to enable those skilled in the art to better understand the technical solution of the present disclosure, and to fully understand and implement how the present disclosure applies technical means to solve technical problems and achieve the corresponding technical effects, the technical solution in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only embodiments of a part of the present disclosure, not all of the embodiments. The embodiments of the present disclosure and the various features in the embodiments can be combined with each other without conflict, and the technical solutions formed are all within the scope of protection of the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present disclosure.

[0046] It should be noted that the terms "first", "second", etc. in the specification and claims of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products, or devices.

[0047] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0048] Embodiment 1

[0049] Figure 1 A schematic diagram of a current increment protection method provided by an embodiment of the present disclosure. Figure 1 As shown, a current increment protection method includes:

[0050] Step S1, obtaining a sampling value sequence i(k) of the feeder current of the traction substation, wherein k is the sampling value sequence number.

[0051] Step S2, based on the sampling value sequence i(k) of the feeder current of the traction substation, calculate the current increment ΔI(k) of the feeder current of the traction substation at the current moment and the total harmonic content K of one cycle time window at the current moment Σ (k), wherein the current increment ΔI(k) of the feeder current of the traction substation at the current moment is the effective value I of the fundamental component of the feeder current of the traction substation at the current moment 1 (k) The effective value of the fundamental component of the previous cycle relative to the current time I 1 (kN) is the current change, where N is the number of sampling points per cycle.

[0052] In some embodiments, the calculation process of the current increment ΔI(k) of the feeder current of the traction substation at the current moment includes:

[0053] Step S21, obtaining a sampling value sequence i(k) of the feeder current of the traction substation in a one-cycle time window at the current moment;

[0054] Step S22, Fourier transform the sampling value sequence i(k) of the feeder current of the traction substation in one cycle time window at the current moment to obtain the real part sequence I of the feeder current of the traction substation in one cycle time window at the current moment 1C (k), imaginary part sequence I 1S (k) and the effective value sequence of the fundamental component I 1 (k);

[0055] Step S23, based on the effective value sequence I of the fundamental component of the feeder current of the traction substation in one cycle time window at the current moment 1 (k) and the effective value I of the fundamental component of the feeder current of the traction substation in the previous cycle at the current moment 1 (kN), calculate the current increment ΔI(k) of the feeder current of the traction substation at the current moment, and the calculation formula is: ΔI(k)=I 1 (k)-I 1 (kN).

[0056] In some embodiments, the total harmonic content K of the feeder current of the traction substation in a cycle time window at the current moment is Σ The calculation process of (k) includes:

[0057] Step S24, the effective value sequence I of the fundamental component of the feeder current of the traction substation in a cycle time window at the current moment 1 (k) is reconstructed to obtain a fundamental component sampling value sequence i′(k) of the feeder current of the traction substation in a one-cycle time window at the current moment.

[0058] Step S25, based on the fundamental component sampling value sequence i′(k) of the feeder current of the traction substation in one cycle time window at the current moment and the sampling value sequence i(k) of the feeder current of the traction substation in one cycle time window at the current moment, calculate the harmonic component sampling value sequence i of the feeder current of the traction substation in one cycle time window at the current moment ∑ , where the calculation formula for the harmonic component sampling value is: ∑ (k) = i(k) - i′(k).

[0059] Step S26, based on the harmonic component sampling value sequence i of the feeder current of the traction substation in one cycle time window at the current moment. ∑ , calculate the total harmonic effective value I of the feeder current of the traction substation in a cycle time window at the current moment Σ (k), where j is the sampling point number within this cycle.

[0060] Step S27, based on the total harmonic effective value I of the feeder current of the traction substation in one cycle time window at the current moment ∑ (k), calculate the total harmonic content K of the feeder current of the traction substation in a cycle time window at the current moment Σ (k), where

[0061] Step S3, according to the current increment ΔI(k) of the feeder current of the traction substation at the current moment and the total harmonic content K of one cycle time window at the current moment Σ (k) Determine whether to start the current increment protection according to the preset current increment protection strategy.

[0062] In some embodiments, Figure 2 As shown, the current increment protection strategy includes:

[0063] When the current increment ΔI(k) of the feeder current of the traction substation at the current moment is greater than or equal to the preset current increment setting value ΔI set , and the total harmonic content K of the feeder current of the traction substation in a cycle time window at the current moment Σ (k) Greater than or equal to the preset total harmonic content blocking setting value K Σ.set , then the current increment protection is locked;

[0064] When the current increment ΔI(k) of the feeder current of the traction substation at the current moment is greater than or equal to the preset current increment setting value ΔI set , and the total harmonic content K of the feeder current of the traction substation in a cycle time window at the current moment Σ (k) is less than the preset total harmonic content lock setting value K Σ.set The duration t reaches the preset current increment protection setting delay value t set , a protection exit command is issued.

[0065] In some embodiments, when the electric traction power supply mode is a direct power supply mode, the feeder current of the traction substation is the feeder contact network current of the traction substation; when the electric traction power supply mode is an AT power supply mode, the feeder current of the traction substation is the difference between the contact network current of the traction substation and the positive feeder current.

[0066] In some embodiments, the current increment protection setting value ΔI set To avoid the maximum current increment value when the operating conditions of the power supply arm change.

[0067] In some embodiments, the total harmonic content blocking setting value K Σ.setTo avoid the minimum total harmonic content value of the feeder current of the traction substation when the operating conditions of the power supply arm change.

[0068] The correctness of the current increment protection method proposed in this application is illustrated below through four examples of normal operating conditions and high-resistance grounding faults of the feeder of an electrified railway traction substation using AT power supply.

[0069] In this example, the current increment protection setting value ΔI set The total harmonic content blocking setting value is 150A, K Σ.set is 2%.

[0070] Example 1, such as Figure 3 The original waveform of the feeder current with excitation inrush current and the effective value curve of the fundamental component are shown in Figure 4 The fundamental wave and harmonic wave diagram of the feeder current original waveform containing excitation inrush current are shown in the figure. Figure 3 and Figure 4 It can be seen that the current increment ΔI calculated after the inrush current is generated is greater than the current increment protection setting value 150A, which satisfies the current increment ΔI(k) greater than or equal to the preset current increment setting value ΔI set Conditions. Figure 5 The total harmonic content of the feeder current including the excitation inrush current and the total harmonic content blocking setting value curve are shown in Figure 5 It can be seen that the total harmonic content of the feeder current K ∑ The minimum value is about 50%, which is 2% greater than the total harmonic content blocking setting value and does not meet the total harmonic content K of the feeder current. ∑ Less than the total harmonic content blocking setting value K Σ.set condition, thus blocking the current increment protection.

[0071] Example 2, such as Figure 6 The original waveform of the feeder current with symmetrical excitation inrush current and the effective value curve of the fundamental component are shown in Figure 7 The fundamental and harmonic waveforms of the feeder current original waveform with symmetrical excitation inrush current are shown in FIG. Figure 6 and Figure 7 It can be seen that the current increment ΔI calculated after the excitation inrush current is generated is greater than the current increment protection setting value 150A, which satisfies the current increment ΔI(k) greater than or equal to the preset current increment setting value ΔI set Conditions. Figure 8 The total harmonic content of the feeder current with symmetrical excitation inrush current and the total harmonic content blocking setting value curve are shown in Figure 8 It can be seen that the total harmonic content of the feeder current K ∑ The minimum value is about 35%, which is 2% greater than the total harmonic content blocking setting value and does not meet the total harmonic content K of the feeder current.∑ Less than the total harmonic content blocking setting value K Σ.set condition, thus blocking the current increment protection.

[0072] Example 3, such as Fig. 9 The original waveform of the feeder current and the effective value curve of the fundamental component of the electric locomotive acceleration condition are shown in FIG. Fig.10 The fundamental wave and harmonic wave of the feeder current original waveform separated from the acceleration condition of the electric locomotive are shown in the figure. Fig. 9 and Fig.10 It can be seen that the current increment ΔI calculated after the excitation inrush current is generated is greater than the current increment protection setting value 150A, which satisfies the current increment ΔI(k) greater than or equal to the preset current increment setting value ΔI set Conditions. Fig.11 The total harmonic content of the feeder current and the total harmonic content blocking setting value curve of the electric locomotive acceleration condition are shown in Fig.11 It can be seen that the total harmonic content of the feeder current K ∑ The minimum value is about 3.5%, which is 2% greater than the total harmonic content blocking setting value and does not meet the total harmonic content K of the feeder current. Σ Less than the total harmonic content blocking setting value K Σ.set condition, thus blocking the current increment protection.

[0073] Example 4: Fig.12 The original waveform of the feeder current and the effective value curve of the fundamental component of the high-resistance grounding fault are shown in Figure 2. Fig.13 The figure shows the fundamental wave and harmonic wave of the feeder current original waveform separated from the high-resistance ground fault. Fig.12 and Fig.13 It can be seen that the current increment value ΔI calculated after the excitation inrush current is generated is greater than the current increment protection setting value 150A, satisfying the current increment ΔI(k) greater than or equal to the preset current increment setting value ΔI set Conditions. Fig.14 The total harmonic content of the feeder current and the total harmonic content blocking setting value curve of the high-resistance grounding fault of this fault are shown in Fig.14 It can be seen that the total harmonic content of the feeder current K ∑ The maximum value is about 1.3%, which is less than the total harmonic content blocking setting value of 2%, satisfying the total harmonic content K of the feeder current. ∑ Less than the total harmonic content blocking setting value K Σ.set Therefore, the current increment protection condition is established and enters the delay stage. If the total harmonic content of the feeder current K ∑ The duration of the current increment protection setting delay value t is less than 2% of the total harmonic content blocking setting value. set , a protection output command is issued to perform current increment protection operation.

[0074] The current increment protection method provided in the present embodiment obtains the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of one cycle time window at the current moment by calculating based on the sampling value sequence of the feeder current of the traction substation; thereby determining whether to start the current increment protection according to the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of one cycle time window at the current moment according to the preset current increment protection strategy, that is, identifying the electric locomotive load and high-resistance grounding fault based on the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of one cycle time window at the current moment, so as to improve the reliability and sensitivity of the current increment protection.

[0075] Embodiment 2

[0076] On the basis of the above embodiments, this embodiment provides a current increment protection device, including an acquisition module, a processing module and a control module, wherein the acquisition module is used to acquire a sampling value sequence of the feeder current of the traction substation. The processing module is used to calculate the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of a cycle time window at the current moment based on the sampling value sequence of the feeder current of the traction substation; the control module is used to determine whether to start the current increment protection according to the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of a cycle time window at the current moment according to the preset current increment protection strategy.

[0077] The incremental protection device provided in this embodiment is used to implement the incremental protection method of the above embodiment, so the specific implementation details are as described in the above embodiment and will not be repeated here.

[0078] The current increment protection device provided in the present embodiment obtains the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of one cycle time window at the current moment by calculating based on the sampling value sequence of the feeder current of the traction substation; thereby determining whether to start the current increment protection according to the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of one cycle time window at the current moment according to the preset current increment protection strategy, that is, identifying the electric locomotive load and high-resistance grounding fault based on the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of one cycle time window at the current moment, so as to improve the reliability and sensitivity of the current increment protection.

[0079] Embodiment 3

[0080] On the basis of the above embodiments, this embodiment provides a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method described in the above embodiments.

[0081] In some implementations of this embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method described in the above embodiment are implemented.

[0082] In some implementations of this embodiment, a computer program product is provided, including a computer program / instructions, and when the computer program is executed by a processor, the steps of the method described in the above embodiment are implemented.

[0083] The processor may include, but is not limited to, one or more processors or microprocessors, etc. Each processor may be an application specific integrated circuit (ASIC), a digital signal processor (DSP), a digital signal processing device (DSPD), a programmable logic device (PLD), a field programmable gate array (FPGA), a controller, a microcontroller, a microprocessor or other electronic components to execute the methods in the above embodiments.

[0084] The computer-readable storage medium may be implemented by any type of volatile or non-volatile storage device or a combination thereof, and the computer-readable storage medium may include but is not limited to, for example, random access memory (RAM), read-only memory (ROM), flash memory, EPROM memory, EEPROM memory, registers, computer storage media (e.g., hard disk, floppy disk, solid-state drive, removable disk, CD-ROM, DVD-ROM, Blu-ray disc, etc.).

[0085] The computer-readable storage medium may also store at least one computer executable program / instruction, which may be, for example, a computer-readable instruction. The computer-readable storage medium includes, but is not limited to, for example, a volatile memory and / or a non-volatile memory. The volatile memory may include, for example, a random access memory (RAM) and / or a cache memory (cache), etc. The computer-readable storage medium may include, for example, a read-only memory (ROM), a hard disk, a flash memory, etc. For example, a non-transitory computer-readable storage medium may be connected to a computing device such as a computer, and then, when the computing device runs the computer-readable instructions stored on the computer-readable storage medium, the various methods described above may be performed.

[0086] In addition, the computer device may also include (but not limited to) a data bus, an input / output (I / O) bus, a display, and input / output devices (eg, keyboard, mouse, speaker, etc.), etc.

[0087] The processor may communicate with external devices via an I / O bus via a wired or wireless network.

[0088] In one embodiment, the at least one computer executable instruction may also be compiled into or constitute a software product / computer program product, wherein one or more computer executable instructions are executed by a processor to perform the various functions and / or method steps in the embodiments described in the present technology.

[0089] In the embodiments provided in the present disclosure, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present disclosure. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the above-mentioned module, program segment or a part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0090] It should be noted that in the present disclosure, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element limited by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0091] Although the embodiments disclosed in the present disclosure are as above, the above contents are only embodiments adopted for facilitating the understanding of the present disclosure and are not intended to limit the present disclosure. Any technician in the technical field to which the present disclosure belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present disclosure, but the scope of patent protection of the present disclosure shall still be subject to the scope defined in the attached claims.

Claims

1. A current increment protection method, characterized in that: include: Obtaining a sampling value sequence of the feeder current of the traction substation; Based on the sampling value sequence of the feeder current of the traction substation, the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of one cycle time window at the current moment are calculated, wherein the current increment of the feeder current of the traction substation at the current moment is the current change amount of the effective value of the fundamental component of the feeder current of the traction substation at the current moment relative to the effective value of the fundamental component of the previous cycle at the current moment; Whether to start the current increment protection is determined according to the current increment of the feeder current of the traction substation at the current moment and the total harmonic content of one cycle time window at the current moment according to the preset current increment protection strategy.

2. The current increment protection method according to claim 1, characterized in that: The current increment protection strategy includes: When the current increment of the feeder current of the traction substation at the current moment is greater than or equal to the preset current increment setting value, and the total harmonic content of the feeder current of the traction substation in one cycle time window at the current moment is greater than or equal to the preset total harmonic content blocking setting value, the current increment protection is blocked; When the current increment of the feeder current of the traction substation at the current moment is greater than or equal to the preset current increment setting value, and the total harmonic content of the feeder current of the traction substation in one cycle time window at the current moment is less than the preset total harmonic content locking setting value for a duration that reaches the preset current increment protection setting delay value, a protection exit command is issued.

3. The current increment protection method according to claim 1, characterized in that: When the electric traction power supply mode is a direct power supply mode, the feeder current of the traction substation is the feeder contact network current of the traction substation; When the electric traction power supply mode is the AT power supply mode, the feeder current of the traction substation is the difference between the contact network current of the traction substation and the positive feeder current.

4. The current increment protection method according to claim 2, characterized in that: The current increment protection setting value is the maximum current increment value when the operating condition of the power supply arm changes.

5. The current increment protection method according to claim 2, characterized in that: The total harmonic content blocking setting value is the minimum total harmonic content value of the feeder current of the traction substation to avoid changes in the operating conditions of the power supply arm.

6. The current increment protection method according to claim 1, characterized in that: The current increment of the feeder current of the traction substation at the current moment calculated based on the sampling value sequence of the feeder current of the traction substation includes: Obtain a sampling value sequence of a cycle time window of the feeder current of the traction substation at the current moment; Performing Fourier transformation on a sampling value sequence of a one-cycle time window of the feeder current of the traction substation at the current moment to obtain an effective value sequence of a fundamental component of a one-cycle time window of the feeder current of the traction substation at the current moment; Based on the effective value sequence of the fundamental component of the feeder current of the traction substation in one cycle time window at the current moment and the effective value of the fundamental component of the feeder current of the traction substation in the previous cycle at the current moment, the current increment of the feeder current of the traction substation at the current moment is calculated.

7. The current increment protection method according to claim 6, characterized in that: The total harmonic content of the feeder current of the traction substation in one cycle time window at the current moment is calculated based on the sampling value sequence of the feeder current of the traction substation, including: Reconstructing the effective value sequence of the fundamental component of the feeder current of the traction substation in one cycle time window at the current moment to obtain the sampling value sequence of the fundamental component of the feeder current of the traction substation in one cycle time window at the current moment; Based on the fundamental component sampling value sequence of the feeder current of the traction substation in one cycle time window at the current moment and the sampling value sequence of the feeder current of the traction substation in one cycle time window at the current moment, the harmonic component sampling value sequence of the feeder current of the traction substation in one cycle time window at the current moment is calculated; Based on the harmonic component sampling value sequence of the feeder current of the traction substation in one cycle time window at the current moment, calculate the total harmonic effective value of the feeder current of the traction substation in one cycle time window at the current moment; Based on the total harmonic effective value of the feeder current of the traction substation in a cycle time window at the current moment, the total harmonic content of the feeder current of the traction substation in a cycle time window at the current moment is calculated.

8. A computer device comprising a memory, a processor and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method according to any one of claims 1 to 7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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