Method, system and device for calculating effective coupling length of cable under HEMP irradiation, medium and product

Abstract

The invention relates to the technical field of power systems, and discloses a method, system, equipment, medium and product for calculating the effective coupling length of a cable under HEMP irradiation, and the method comprises the steps: segmenting a target transmission cable to obtain multiple segments of sub-transmission cables, constructing an HEMP coupling simulation model of the sub-transmission cables for each segment of sub-transmission cable, and calculating the effective coupling length of the cable under HEMP irradiation. The simulation length of the sub-transmission cable is gradually increased according to the preset length step length, the coupling signal response peak value of the HEMP coupling simulation model after HEMP excitation is obtained after the preset length step length is increased every time, and the effective coupling length of the sub-transmission cable is judged according to the coupling signal response peak value change rate of the adjacent preset length step length. And the total effective coupling length of the target transmission cable is determined according to the effective coupling length of each section of sub-transmission cable, so that the accuracy and reliability of calculation of the effective coupling length of the cable under HEMP irradiation are effectively improved.

Description

Technical Field

[0001] This invention relates to the field of power system technology, and in particular to a method, system, device, medium and product for calculating the effective coupling length of cables under HEMP irradiation. Background Technology

[0002] As a critical node in the power system, the operational safety of substations is significantly affected by electromagnetic interference. High-altitude electromagnetic pulses (HEMPs), as strong sources of electromagnetic interference, can generate strong current / voltage signals through cable coupling, leading to relay protection malfunctions and equipment damage. To assess the impact of HEMPs on substations, an electromagnetic coupling simulation model of cables needs to be established.

[0003] In existing technologies, substation cable modeling often uses actual lengths (hundreds of meters). However, because substations occupy a large area (tens of thousands of square meters), modeling actual lengths will generate millions of meshes, resulting in simulations taking several days, which is difficult to meet the rapid iteration requirements of engineering design.

[0004] For cables in substations, the coupling signal of HEMP stops increasing once the cable length reaches a certain point; that is, there is an effective length for the cable when HEMP irradiates it. Therefore, the simulation proposes to use an effective coupling length analysis method to simplify the cable length in substations, thereby improving calculation speed while ensuring the validity of the simulation results.

[0005] Currently, effective coupling length analysis methods have poor coverage performance and adaptability, making it difficult to improve computational speed while ensuring the validity of simulation results. Summary of the Invention

[0006] In view of this, the present invention provides a method, system, device, medium and product for calculating the effective coupling length of cables under HEMP irradiation, which solves the technical problems of poor coverage performance, poor adaptability and difficulty in improving calculation speed while ensuring the validity of simulation results in existing effective coupling length analysis methods.

[0007] The first aspect of this invention provides a method for calculating the effective coupling length of a cable under HEMP irradiation, comprising:

[0008] Based on the cable layout structure of the substation, the target transmission cable is segmented to obtain multiple segments of transmission cable.

[0009] For each segment of the sub-transmission cable, based on the structural parameters of the sub-transmission cable and using HEMP plane waves as the excitation source, a HEMP coupling simulation model of the sub-transmission cable is constructed.

[0010] The simulation length of the sub-transmission cable in the HEMP coupling simulation model is gradually increased by a preset length step, and the peak value of the coupling signal response of the HEMP coupling simulation model after being excited by the excitation source is obtained after each increase of the preset length step.

[0011] Based on the peak value of the coupled signal response after each increase of the preset length step, determine the rate of change of the peak value of the coupled signal response for adjacent preset length steps;

[0012] If the rate of change of the peak value of the coupled signal response reaches the preset convergence condition, then the latest simulated length of the sub-transmission cable in the HEMP coupling simulation model is determined as the effective coupling length of the sub-transmission cable.

[0013] The total effective coupling length of the target transmission cable is determined based on the effective coupling length of each segment of the sub-transmission cable.

[0014] Preferably, the step of segmenting the target transmission cable according to the cable layout structure of the substation to obtain multiple sub-segments of transmission cable includes:

[0015] Based on the cable routing of the target transmission cable, identify multiple connection turning points of the target transmission cable;

[0016] The target transmission cable is segmented according to multiple connection turning points to obtain multiple sub-transmission cables.

[0017] Preferably, the step of constructing a HEMP coupling simulation model of the sub-transmission cable based on its structural parameters and using a HEMP plane wave as the excitation source includes:

[0018] Based on the structural parameters of the sub-transmission cable, determine the equivalent circuit model parameters of the sub-transmission cable;

[0019] The excitation parameters of the excitation source are determined based on the electric field strength, magnetic field strength, and incident angle of the HEMP plane wave.

[0020] Based on the equivalent circuit model parameters and the excitation parameters, an HEMP coupling simulation model of the sub-transmission cable is constructed using electromagnetic simulation software.

[0021] Preferably, the step of gradually increasing the simulation length of the sub-transmission cable in the HEMP coupling simulation model by a preset length step, and obtaining the peak value of the coupling signal response of the HEMP coupling simulation model after being excited by the excitation source after each increase of the preset length step, includes:

[0022] Initialize the simulation length of the sub-transmission cable in the HEMP coupled simulation model;

[0023] The preset length step is obtained, and the simulation length of the sub-transmission cable is gradually increased in units of the preset length step. After each increase, the HEMP coupling simulation model is run to obtain the peak value of the coupling signal response of the preset monitoring point in the HEMP coupling simulation model after being excited by the excitation source. The preset monitoring point is at least located on the shielding layer, armor layer or core wire of the sub-transmission cable.

[0024] Preferably, the method further includes:

[0025] If the rate of change of the peak value of the coupled signal response does not reach the preset convergence condition, then continue.

[0026] The simulation length of the sub-transmission cable in the HEMP coupling simulation model is gradually increased by a preset length step. After each increase of the preset length step, the peak value of the coupling signal response of the HEMP coupling simulation model after being excited by the excitation source is obtained until the rate of change of the peak value of the coupling signal response reaches the preset convergence condition, or the simulation length of the sub-transmission cable reaches the preset maximum length. Then, the latest simulation length of the sub-transmission cable in the HEMP coupling simulation model is output.

[0027] Preferably, the method further includes:

[0028] When the target transmission cable has a cable structure consisting of multiple parallel cables, the interference coefficient is determined based on the number of parallel cables and the cable spacing.

[0029] The effective coupling length of each segment of the sub-transmission cable is corrected according to the interference coefficient to obtain the corrected effective coupling length.

[0030] Accordingly, determining the total effective coupling length of the target transmission cable based on the effective coupling length of each segment of the sub-transmission cable includes:

[0031] The total effective coupling length of the target transmission cable is determined based on the corrected effective coupling length of each segment of the sub-transmission cable.

[0032] Secondly, the present invention also provides a system for calculating the effective coupling length of cables under HEMP irradiation, comprising:

[0033] The cable segmentation module is used to segment the target transmission cable according to the cable layout structure of the substation, so as to obtain multiple segments of transmission cable.

[0034] The simulation model construction module is used to construct a HEMP coupled simulation model of each sub-transmission cable segment based on the structural parameters of the sub-transmission cable and using HEMP plane waves as the excitation source.

[0035] The coupling signal response module is used to gradually increase the simulation length of the sub-transmission cable in the HEMP coupling simulation model by a preset length step, and to obtain the peak value of the coupling signal response of the HEMP coupling simulation model after being excited by the excitation source after each increase of the preset length step.

[0036] The peak change analysis module is used to determine the rate of change of the peak value of the coupled signal response for adjacent preset length steps based on the peak value of the coupled signal response after each increase of the preset length step.

[0037] The effective length determination module is used to determine the latest simulated length of the sub-transmission cable in the HEMP coupling simulation model as the effective coupling length of the sub-transmission cable when the peak change rate of the coupled signal response reaches a preset convergence condition.

[0038] The total effective length determination module is used to determine the total effective coupling length of the target transmission cable based on the effective coupling length of each segment of the sub-transmission cable.

[0039] Thirdly, the present invention also provides an electronic device, the electronic device including a memory and a processor, the memory storing a computer program, the computer program being executed by the processor causing the processor to perform the steps of the method for calculating the effective coupling length of a cable under HEMP irradiation as described in the first aspect.

[0040] Fourthly, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements the steps of the method for calculating the effective coupling length of a cable under HEMP irradiation as described in the first aspect.

[0041] Fifthly, the present invention also provides a computer program product comprising a computer program stored on a non-transitory computer-readable storage medium, the computer program comprising program instructions, wherein, when the program instructions are executed by a computer, the computer performs the steps of the method for calculating the effective coupling length of a cable under HEMP irradiation as described in the first aspect.

[0042] As can be seen from the above technical solution, this invention segments the target transmission cable to obtain multiple sub-transmission cables. For each sub-transmission cable, a HEMP coupling simulation model is constructed. The simulation length of the sub-transmission cable is gradually increased in preset length steps. After each increase in the preset length step, the peak value of the coupling signal response of the HEMP coupling simulation model after HEMP excitation is obtained. The effective coupling length of the sub-transmission cable is determined by the rate of change of the peak value of the coupling signal response of adjacent preset length steps. Based on the effective coupling length of each sub-transmission cable segment, the total effective coupling length of the target transmission cable is determined. Thus, by fully considering the actual cable layout structure, segmenting and simulating the cable, and using the rate of change of the peak response as a criterion, the accuracy and reliability of the calculation of the effective coupling length of the cable under HEMP irradiation are effectively improved, and the calculation speed is increased while ensuring the validity of the simulation results. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is an application environment diagram of a method for calculating the effective coupling length of a cable under HEMP irradiation, provided in an embodiment of the present invention.

[0045] Figure 2 A flowchart illustrating a method for calculating the effective coupling length of a cable under HEMP irradiation, provided as an embodiment of the present invention;

[0046] Figure 3 A simplified layout diagram of substation cables;

[0047] Figure 4 This is a diagram showing the current variation in the shielding layer on the main control room side of the first cable segment;

[0048] Figure 5 This is a diagram showing the current variation in the shielding layer on the terminal box side of the first cable segment;

[0049] Figure 6 This is a diagram showing the voltage variation on the main control room side of the first section of cable;

[0050] Figure 7 This is a diagram showing the voltage variation on the terminal box side of the first cable segment;

[0051] Figure 8 This is a diagram showing the current variation in the shielding layer on the main control room side of the second cable segment;

[0052] Figure 9 This is a diagram showing the current variation in the shielding layer on the terminal box side of the second cable segment;

[0053] Figure 10 This is a diagram showing the voltage variation on the main control room side of the second cable section;

[0054] Figure 11 This is a diagram showing the voltage variation on the terminal box side of the second cable segment;

[0055] Figure 12 This is a diagram showing the current variation in the shielding layer on the main control room side of the third cable segment;

[0056] Figure 13 This is a diagram showing the current variation in the shielding layer on the terminal box side of the third cable segment;

[0057] Figure 14 This is a diagram showing the voltage variation on the main control room side of the third cable segment;

[0058] Figure 15 This is a diagram showing the voltage variation on the terminal box side of the third cable segment;

[0059] Figure 16 This is a diagram showing the current variation in the shielding layer on the main control room side of the fourth cable segment;

[0060] Figure 17 This is a diagram showing the current variation in the shielding layer on the terminal box side of the fourth cable segment;

[0061] Figure 18 This is a diagram showing the voltage variation on the main control room side of the fourth cable segment;

[0062] Figure 19 This is a diagram showing the voltage variation on the terminal box side of the fourth cable segment;

[0063] Figure 20 A schematic diagram of a system for calculating the effective coupling length of a cable under HEMP irradiation, provided in an embodiment of the present invention;

[0064] Figure 21 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0065] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0066] The effective coupling length calculation method for cables under HEMP irradiation provided in this application embodiment can be applied to, for example... Figure 1 The application environment shown is illustrated. Terminal 101 communicates with server 102 via a network. A data storage system can store the data that server 102 needs to process. The data storage system can be integrated onto server 102, or it can be located in the cloud or on another network server. Terminal 101 or server 102 segments the target transmission cable according to the cable layout structure of the substation, obtaining multiple sub-transmission cable segments. For each sub-transmission cable segment, based on its structural parameters and using a HEMP plane wave as the excitation source, a HEMP coupling simulation model of the sub-transmission cable is constructed. The simulation length of the sub-transmission cable in the HEMP coupling simulation model is gradually increased in preset length steps, and the peak value of the coupling signal response after excitation by the excitation source is obtained after each preset length step. Based on the peak value of the coupling signal response after each preset length step, the rate of change of the peak value of the coupling signal response of adjacent preset length steps is determined. When the rate of change of the peak value of the coupling signal response reaches a preset convergence condition, the latest simulation length of the sub-transmission cable in the HEMP coupling simulation model is determined as the effective coupling length of the sub-transmission cable. Based on the effective coupling length of each segment of the transmission cable, the total effective coupling length of the target transmission cable is determined.

[0067] Terminal 101 can be, but is not limited to, various personal computers, laptops, smartphones, and tablets.

[0068] Server 102 can be a standalone physical server, a server cluster or distributed system consisting of multiple physical servers, or a cloud server that provides cloud computing services.

[0069] like Figure 2 As shown, this application provides a method for calculating the effective coupling length of a cable under HEMP irradiation, which is then applied to... Figure 1 Taking terminal 101 or server 102 as an example, the explanation includes the following steps S1 to S6. Wherein:

[0070] Step S1: Based on the cable layout structure of the substation, the target transmission cable is segmented to obtain multiple segments of transmission cable.

[0071] The target transmission cables should be the transmission cables between various devices in the substation, such as switch transmission cables, analog transmission cables, control cables, and power cables.

[0072] When dividing the target transmission cable into detailed segments based on the cable layout structure of the substation, it is necessary to fully consider its route, connection points, and any special structures that may exist, to ensure that the division of each segment of the transmission cable not only conforms to the actual wiring situation, but also facilitates subsequent simulation analysis and calculation.

[0073] Step S2: For each sub-transmission cable segment, based on the structural parameters of the sub-transmission cable and using HEMP plane wave as the excitation source, construct a HEMP coupled simulation model of the sub-transmission cable.

[0074] The structural parameters of the sub-transmission cable include information such as cable type, conductor radius, insulation thickness, shielding layer, and armor / core characteristics. Meanwhile, the HEMP plane wave, as the excitation source, requires its electric field strength, magnetic field strength, waveform parameters, polarization, and incident angle to be set closely to the characteristics of HEMP irradiation in the actual environment to ensure the accuracy and reliability of the simulation results.

[0075] Step S3: Gradually increase the simulation length of the sub-transmission cable in the HEMP coupling simulation model by a preset length step, and obtain the peak value of the coupling signal response of the HEMP coupling simulation model after being excited by the excitation source after each increase of the preset length step.

[0076] By setting a fixed length step and gradually increasing the simulation length of the sub-transmission cable in fixed steps, the changes in the coupling characteristics of the cable under different lengths can be systematically investigated. After each increase in the preset length step, the HEMP coupling simulation model is run to accurately obtain the peak value of the coupling signal response after the model is excited by the excitation source.

[0077] Step S4: Determine the rate of change of the peak value of the coupled signal response for adjacent preset length steps based on the peak value of the coupled signal response after each increase of the preset length step.

[0078] The peak value of the coupled signal response can be determined by monitoring the coupled signal response waveform, which can be a current waveform or a voltage waveform. A peak detection algorithm is used to detect the peak value of the coupled signal response waveform. The rate of change of the peak value of the coupled signal response is then:

[0079] Δ=|(P L -P {L-ΔL} ) / P {L-ΔL} |×100%

[0080] In the formula, Δ is the rate of change of the peak value of the coupled signal response, and P L P represents the peak value of the coupled signal response corresponding to length L. {L-ΔL} The peak value of the coupled signal response corresponding to the simulation length L-ΔL is given, where ΔL is the preset length step.

[0081] Step S5: When the peak change rate of the coupled signal response reaches the preset convergence condition, the latest simulated length of the sub-transmission cable in the HEMP coupling simulation model is determined as the effective coupling length of the sub-transmission cable.

[0082] The preset convergence condition is that when the peak change rate of the coupled signal response is less than a preset threshold (e.g., 5%) and continues for a preset number of length steps (i.e., 3), it indicates that the change of the HEMP coupled signal has stabilized within that length range, and the convergence condition has been met. Therefore, the latest simulated length of the current sub-transmission cable can be determined as its effective coupling length. This criterion ensures the accuracy and stability of the effective coupling length, avoiding misjudgments of the simulated length due to signal fluctuations or simulation errors. In practical applications, the specific values ​​of the preset threshold and the preset number of length steps can be flexibly adjusted according to actual needs and simulation accuracy to achieve optimal calculation results.

[0083] Step S6: Determine the total effective coupling length of the target transmission cable based on the effective coupling length of each segment of the transmission cable.

[0084] The sum of the effective coupling lengths of each segment of the transmission cable is the total effective coupling length of the target transmission cable.

[0085] It should be noted that, in this embodiment, the target transmission cable is segmented to obtain multiple sub-transmission cables. For each sub-transmission cable, a HEMP coupling simulation model is constructed. The simulation length of the sub-transmission cable is gradually increased in preset length steps. After each increase in the preset length step, the peak value of the coupling signal response of the HEMP coupling simulation model after HEMP excitation is obtained. The effective coupling length of the sub-transmission cable is determined by the rate of change of the peak value of the coupling signal response of adjacent preset length steps. Based on the effective coupling length of each sub-transmission cable segment, the total effective coupling length of the target transmission cable is determined. Thus, by fully considering the actual cable layout structure, segmenting and simulating the cable, and using the rate of change of the peak response as a criterion, the accuracy and reliability of the calculation of the effective coupling length of the cable under HEMP irradiation are effectively improved, and the calculation speed is increased while ensuring the validity of the simulation results.

[0086] In some embodiments, the target transmission cable is segmented according to the cable layout structure of the substation to obtain multiple segments of transmission cable, including:

[0087] Step S101: Identify multiple connection turning points of the target transmission cable based on the cable layout of the target transmission cable.

[0088] The routing of transmission cables within substations is often complex, with multiple connection and turning points. These points may be cable branching points, equipment connection points, or locations where the cable route changes significantly. Careful analysis of cable layout drawings or on-site surveys can accurately identify these critical nodes. For example, in some large substations, cables may originate from the main control room, pass through multiple switchgear cabinets, and finally connect to the terminal box. In this process, the connection points of each switchgear cabinet and the places where the cable route changes are the connection and turning points. For example:

[0089] From the connection point from the main control room to the first switch cabinet, and the connection point from the first switch cabinet to the second switch cabinet, these nodes divide the entire target transmission cable into multiple sub-segments with different routes and connection relationships.

[0090] Step S102: Divide the target transmission cable into segments according to multiple connection turning points to obtain multiple segments of transmission cable.

[0091] The target transmission cable is segmented using each connection turning point as a dividing point to obtain multiple segments of transmission cable.

[0092] In some embodiments, based on the structural parameters of the sub-transmission cable and using a HEMP plane wave as the excitation source, a HEMP coupling simulation model of the sub-transmission cable is constructed, including:

[0093] Step S201: Determine the equivalent circuit model parameters of the sub-transmission cable based on its structural parameters.

[0094] The structural parameters of the sub-transmission cable directly determine the values ​​of its equivalent circuit model parameters. For example, the cable type affects parameters such as resistance and inductance in the equivalent circuit; the conductor radius affects the resistance; the insulation thickness affects the capacitance; and the presence of shielding and armor layers introduces additional inductance and capacitance effects, altering the topology of the equivalent circuit. Through detailed analysis and calculation of these structural parameters, the equivalent circuit model parameters of the sub-transmission cable can be accurately determined.

[0095] The switch signal transmission cable features a single-layer shielding structure (0.2mm thick, copper material) and a single-layer armor layer (composed of 1.0mm diameter galvanized steel wire), containing four core conductors (1.5mm² cross-sectional area). 2 (Material is copper). The shielding layer is grounded at both ends, and the armor layer and the core wire are in an open circuit state.

[0096] Analog transmission cable: Features a double-shielded structure (inner shielding layer 0.15mm thick, made of copper; outer shielding layer 0.2mm thick, made of aluminum), and includes 2 core conductors (conductor cross-sectional area 2.5mm²).2 The inner shielding layer is grounded at one end, the outer shielding layer is grounded at both ends, and the core wire is in an open circuit state.

[0097] Control cable: Employs a single-layer shielded structure (0.18mm thick, copper material), containing 8 core conductors (1.0mm² cross-sectional area). 2 The shielding layer is grounded at both ends, and the core wire is connected to the equipment impedance (impedance range is 1kΩ-10kΩ).

[0098] Power cable: Unshielded, consisting of 3 core conductors (50mm² cross-sectional area). 2 The core wire is connected to the transformer impedance (impedance range is 0.1Ω-1Ω).

[0099] Step S202: Determine the excitation parameters of the excitation source based on the electric field strength, magnetic field strength, and incident angle of the HEMP plane wave.

[0100] The excitation parameters are determined according to the IEC61000-2-9 standard and the electromagnetic environment assessment of the substation area. These parameters include: electric field strength E ∈ {30kV / m, 40kV / m, 50kV / m} (corresponding to different HEMP intensity levels); magnetic field strength H ∈ {0.1A / m, 0.2A / m, 0.3A / m} (matching the electric field strength level); and incident angles set based on the actual substation layout and possible HEMP irradiation directions, such as incident angle θ ∈ {0° (vertical), 30°, 45°, 60°}, and polarization ∈ {horizontal polarization, vertical polarization}. Waveform parameters include: leading edge time t1 ∈ {1.8ns, 2.3ns, 2.5ns}, and half-width time t2 ∈ {20ns, 23ns, 25ns}.

[0101] Step S203: Combining the equivalent circuit model parameters and excitation parameters, construct the HEMP coupling simulation model of the sub-transmission cable using electromagnetic simulation software.

[0102] Electromagnetic simulation software such as CST and HFSS possess powerful electromagnetic field calculation capabilities, enabling them to accurately simulate the electromagnetic coupling process of transmission cables under HEMP irradiation based on input equivalent circuit model parameters and excitation parameters. When constructing the simulation model, the equivalent circuit model parameters must be accurately input into the software, including the values ​​of components such as resistors, inductors, and capacitors, as well as their interconnections. Simultaneously, the excitation parameters must be set to values ​​that match the actual HEMP irradiation characteristics, such as electric field strength, magnetic field strength, incident angle, polarization, and waveform parameters. Through software simulation calculations, the field boundary adopts an absorbing boundary (simulating infinite space to avoid boundary reflection interference), the cable's shielding / armor layer is modeled using thin-shell elements, the core wire is modeled using cylindrical elements, and the space between the core wire and the shielding layer is filled with an insulating medium (relative permittivity ε).ᵣ =2.5), the termination impedance is such that the grounding end is connected to a 1Ω resistor (equivalent to actual grounding), and the open circuit end is connected to a 1MΩ resistor (equivalent to actual open circuit). This can obtain the coupling signal response of the sub-transmission cable under HEMP irradiation, including waveform data such as current and voltage.

[0103] In some embodiments, the simulation length of the sub-transmission cable in the HEMP coupling simulation model is gradually increased by a preset length step, and after each increase of the preset length step, the peak value of the coupling signal response of the HEMP coupling simulation model after being excited by the excitation source is obtained, including:

[0104] Step 301: Initialize the simulation length of the sub-transmission cable in the HEMP coupled simulation model.

[0105] Before simulation, the simulation length of the sub-transmission cable can be initialized to an initial preset value. This initial preset value can be reasonably set according to actual needs and the approximate length range of the cable. For example, if the overall length of the cable is expected to be between tens and hundreds of meters, the initial preset value can be set to 10 meters.

[0106] Step 302: Obtain the preset length step and gradually increase the simulation length of the sub-transmission cable in units of the preset length step. After each increase, run the HEMP coupling simulation model to obtain the peak value of the coupling signal response of the preset monitoring point in the HEMP coupling simulation model after being excited by the excitation source. The preset monitoring point is at least set on the shielding layer, armor layer or core wire of the sub-transmission cable.

[0107] The selection of the preset length step size needs to comprehensively consider both computational accuracy and efficiency. A step size that is too small, while improving accuracy, will increase the computational load, while a step size that is too large may lead to the omission of crucial information. Typically, it can be set according to the cable type and simulation objective; for example, 0.1 meters can be set for detailed analysis, and 1 meter for preliminary estimation. After each increase in the preset length step size, the HEMP coupled simulation model is run. Using the software's built-in monitoring function or a custom script, the peak value of the coupled signal response at the preset monitoring points (such as the shielding layer, armor layer, or core wire) after being excited by the excitation source is accurately obtained.

[0108] In some embodiments, the method further includes:

[0109] If the rate of change of the peak value of the coupled signal response does not reach the preset convergence condition, then continue.

[0110] The simulation length of the sub-transmission cable in the HEMP coupling simulation model is gradually increased by a preset length step. After each increase of the preset length step, the peak value of the coupling signal response of the HEMP coupling simulation model after being excited by the excitation source is obtained until the rate of change of the peak value of the coupling signal response reaches the preset convergence condition, or the simulation length of the sub-transmission cable reaches the preset maximum length. Then, the latest simulation length of the sub-transmission cable in the HEMP coupling simulation model is output.

[0111] The preset maximum length is determined by the actual total length of the sub-transmission cable. If the rate of change of the peak value of the coupled signal response does not reach the preset convergence condition, the simulated length of the sub-transmission cable continues to increase gradually according to the preset length increment. After each increment, the HEMP coupling simulation model is rerun, and the peak value of the coupled signal response after excitation by the excitation source at the preset monitoring point is obtained. This process continues until one of the following two conditions is met: first, the rate of change of the peak value of the coupled signal response reaches the preset convergence condition, indicating that the change of the HEMP coupled signal has stabilized within this length range, and there is no need to continue increasing the length; second, the simulated length of the sub-transmission cable reaches the preset maximum length, which is set based on the actual total length of the sub-transmission cable to ensure that the simulation process does not exceed the actual range of the cable. When either of the above conditions is met, the simulation process stops, and the latest simulated length of the sub-transmission cable in the HEMP coupling simulation model is output. This length is the effective coupling length of the sub-transmission cable under given conditions.

[0112] In some embodiments, the method further includes:

[0113] Step S51: If the target transmission cable has a multi-parallel cable structure, the interference coefficient is determined based on the number of parallel cables and the cable spacing.

[0114] In a common configuration, multiple parallel cables form a structure where the target transmission cable is arranged alongside other transmission cables. In this configuration, interference arises between the cables due to electromagnetic coupling, affecting their effective coupling length. The interference coefficient is a parameter used to quantify the degree of this interference; its value is obtained by linearly fitting the number of parallel cables and the spacing between them. The interference coefficient is:

[0115]

[0116] In the formula, k is the interference coefficient, n is the number of parallel cables, and D is the cable spacing.

[0117] Step S52: Correct the effective coupling length of each segment of the transmission cable according to the interference coefficient to obtain the corrected effective coupling length.

[0118] The corrected effective coupling length for each segment of the transmission cable is:

[0119] L' x =k×L x

[0120] In the formula, L' x L is the corrected effective coupling length. x This is the effective coupling length before correction.

[0121] Accordingly, based on the effective coupling length of each segment of the transmission cable, the total effective coupling length of the target transmission cable is determined, including:

[0122] The total effective coupling length of the target transmission cable is determined based on the corrected effective coupling length of each segment of the transmission cable.

[0123] The total effective coupling length of the target transmission cable is obtained by adding the corrected effective coupling lengths of each segment of the transmission cable.

[0124] The following is a calculation example of a method for calculating the effective coupling length of a cable under HEMP irradiation proposed in this application.

[0125] In this example, such as Figure 3 As shown, Figure 3 The diagram illustrates the switch signal transmission cable from the main control room to the terminal box section. The cable shield is grounded at both ends, and the armor layer and core wire are open circuits. The cable is terminated with an equivalent grounding state of 1Ω impedance and an equivalent open circuit state of 1MΩ impedance. N1 simulates the main control room side, and N2 simulates the terminal box side.

[0126] right Figure 3 The switch signal transmission cable is divided into four segments: cable a (total length 30m), cable b (total length 50m), cable c (total length 40m), and cable d (total length 30m).

[0127] For the first cable segment a, the excitation source is a plane wave incident at the angle. This refers to a vertically incident, horizontally polarized HEMP, with an electric field waveform that meets IEC standards: an amplitude of 50 kV / m, a leading edge of 2.3 ns, and a half-width of 23 ns, forming a double exponential wave. Initial length... =5m, step size ΔL=1m, gradually increasing to L=30m; for each length L, the simulation results are as follows Figure 4 and Figure 5 The current waveforms of the shielding layer on the main control room side and the shielding layer on the terminal box side are shown respectively. Figure 6 and Figure 7The trends of peak voltage on the main control room side and peak voltage on the terminal box side with cable length are shown respectively. It can be seen that as the cable length increases, the peak values ​​of shield current, armor voltage, and core wire voltage at both ends of the cable do not change significantly. Therefore, the effective coupling length of the first cable segment is 10m, and the simulation model can simplify the first cable segment a to a 10m long transmission cable.

[0128] For the second cable segment b, the excitation source is a plane wave incident angle. This refers to a vertically incident, horizontally polarized HEMP, with an electric field waveform that meets IEC standards: an amplitude of 50 kV / m, a leading edge of 2.3 ns, and a half-width of 23 ns, forming a double exponential wave. Initial length... =10m, step size ΔL=2m, increased to L=50m; for each length L, the simulation results are as follows Figure 8 and Figure 9 The current waveforms of the shielding layer on the main control room side and the shielding layer on the terminal box side are shown respectively. Figure 10 and Figure 11 The trends of peak voltage on the main control room side and peak voltage on the terminal box side with cable length are shown respectively. It can be seen that as the cable length increases, the peak values ​​of shield current, armor voltage, and core wire voltage at both ends of the cable do not change significantly. Therefore, the effective coupling length of the second cable segment is 25m, and the simulation model can simplify the second cable segment b to a 25m long transmission cable.

[0129] For the third cable segment c, the excitation source is a plane wave incident angle. This refers to a vertically incident, horizontally polarized HEMP, with an electric field waveform that meets IEC standards: an amplitude of 50 kV / m, a leading edge of 2.3 ns, and a half-width of 23 ns, forming a double exponential wave. Initial length... =8m, step size ΔL=2m, increased to L=40m; for each length L, the simulation results are as follows Figure 12 and Figure 13 The current waveforms of the shielding layer on the main control room side and the shielding layer on the terminal box side are shown respectively. Figure 14 and Figure 15 The trends of peak voltage on the main control room side and peak voltage on the terminal box side with cable length are shown respectively. It can be seen that as the cable length increases, the peak values ​​of shield current, armor voltage, and core wire voltage at both ends of the cable do not change significantly. Therefore, the effective coupling length of the third cable segment is 20m, and the simulation model can simplify the third cable segment c to a 20m long transmission cable.

[0130] For the fourth cable segment d, the excitation source is a plane wave incident angle. This refers to a vertically incident, horizontally polarized HEMP, with an electric field waveform that meets IEC standards: an amplitude of 50 kV / m, a leading edge of 2.3 ns, and a half-width of 23 ns, forming a double exponential wave. Initial length... =5m, step size ΔL=1m, increased to L=30m; for each length L, the simulation results are as follows Figure 16 and Figure 17 The current waveforms of the shielding layer on the main control room side and the shielding layer on the terminal box side are shown respectively. Figure 18 and Figure 19 The trends of peak voltage on the main control room side and the terminal box side with cable length are shown respectively. It can be seen that as the cable length increases, the peak values ​​of the shield current, armor voltage, and core wire voltage at both ends of the cable do not change significantly. Therefore, the effective coupling length of the fourth cable segment is 10m, and the simulation model can simplify the fourth cable segment d to a 10m long transmission cable. Summing the effective coupling lengths of the four cable segments, the effective coupling length of the switch quantity transmission cable from the main control room to the terminal box is 65m.

[0131] Based on the same inventive concept, this application also provides a system for calculating the effective coupling length of cables under HEMP irradiation, which is used to implement the above-mentioned method for calculating the effective coupling length of cables under HEMP irradiation.

[0132] The solution provided by this system is similar to the solution described in the above method. Therefore, the specific limitations of one or more embodiments of the effective coupling length calculation system for cables under HEMP irradiation provided below can be found in the limitations of the effective coupling length calculation method for cables under HEMP irradiation described above, and will not be repeated here.

[0133] like Figure 20 As shown in the figure, this application provides a system for calculating the effective coupling length of a cable under HEMP irradiation, including:

[0134] The cable segmentation module 100 is used to segment the target transmission cable according to the cable layout structure of the substation to obtain multiple segments of transmission cable.

[0135] The simulation model building module 200 is used to construct a HEMP coupled simulation model of each sub-transmission cable based on the structural parameters of the sub-transmission cable and combined with HEMP plane wave as the excitation source.

[0136] The coupling signal response module 300 is used to gradually increase the simulation length of the sub-transmission cable in the HEMP coupling simulation model by a preset length step, and to obtain the peak value of the coupling signal response of the HEMP coupling simulation model after being excited by the excitation source after each increase of the preset length step.

[0137] The peak change analysis module 400 is used to determine the rate of change of the peak value of the coupled signal response for adjacent preset length steps based on the peak value of the coupled signal response after each increase of a preset length step.

[0138] The effective length determination module 500 is used to determine the latest simulated length of the sub-transmission cable in the HEMP coupling simulation model as the effective coupling length of the sub-transmission cable when the peak change rate of the coupled signal response reaches the preset convergence condition.

[0139] The total effective length determination module 600 is used to determine the total effective coupling length of the target transmission cable based on the effective coupling length of each segment of the transmission cable.

[0140] In some embodiments, the cable segmentation module 100 is used for:

[0141] Based on the cable routing of the target transmission cable, identify multiple connection and turning points of the target transmission cable;

[0142] The target transmission cable is segmented based on multiple connection turning points to obtain multiple segments of transmission cable.

[0143] In some embodiments, the simulation model building module 200 is used for:

[0144] Based on the structural parameters of the sub-transmission cable, determine the equivalent circuit model parameters of the sub-transmission cable;

[0145] The excitation parameters of the excitation source are determined based on the electric field strength, magnetic field strength, and incident angle of the HEMP plane wave.

[0146] By combining the parameters of the equivalent circuit model and the excitation parameters, a HEMP coupling simulation model of the sub-transmission cable is constructed using electromagnetic simulation software.

[0147] In some embodiments, the coupling signal response module 300 is used for:

[0148] Initialize the simulation length of the sub-transmission cable in the HEMP coupled simulation model;

[0149] Obtain a preset length step and gradually increase the simulation length of the sub-transmission cable in units of the preset length step. After each increase, run the HEMP coupling simulation model and obtain the peak value of the coupling signal response of the preset monitoring point in the HEMP coupling simulation model after being excited by the excitation source. The preset monitoring point is at least set on the shielding layer, armor layer or core wire of the sub-transmission cable.

[0150] In some embodiments, the effective length determining module 500 is further configured to:

[0151] If the rate of change of the peak value of the coupled signal response does not reach the preset convergence condition, then continue.

[0152] The simulation length of the sub-transmission cable in the HEMP coupling simulation model is gradually increased by a preset length step. After each increase of the preset length step, the peak value of the coupling signal response of the HEMP coupling simulation model after being excited by the excitation source is obtained until the rate of change of the peak value of the coupling signal response reaches the preset convergence condition, or the simulation length of the sub-transmission cable reaches the preset maximum length. Then, the latest simulation length of the sub-transmission cable in the HEMP coupling simulation model is output.

[0153] In some embodiments, the system further includes: a correction module, configured to:

[0154] When the target transmission cable has a structure of multiple parallel cables, the interference coefficient is determined based on the number of parallel cables and the cable spacing.

[0155] The effective coupling length of each segment of the transmission cable is corrected based on the interference coefficient to obtain the corrected effective coupling length;

[0156] Accordingly, the total effective length determination module 600 is used for:

[0157] The total effective coupling length of the target transmission cable is determined based on the corrected effective coupling length of each segment of the transmission cable.

[0158] like Figure 21 As shown, this application provides an electronic device 10, which includes a memory 20 and a processor 30. The memory 20 stores a computer program. When the computer program is executed by the processor 30, the processor 30 performs the steps of the effective coupling length calculation method for cables under HEMP irradiation as described in the above embodiment.

[0159] This application provides a computer-readable storage medium storing a computer program thereon. When the computer program is executed, it implements the steps of the method for calculating the effective coupling length of a cable under HEMP irradiation as described in the above embodiments.

[0160] This application provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions, wherein when the program instructions are executed by a computer, the computer performs the steps of the effective coupling length calculation method for cables under HEMP irradiation as described in the above embodiments.

[0161] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, electronic devices, computer storage media, and computer program products described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0162] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0163] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0164] In the several embodiments provided by this invention, it should be understood that the disclosed systems, electronic devices, computer storage media, computer program products, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, indirect coupling or communication connection between devices or units, and may be electrical, mechanical, or other forms.

[0165] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0166] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0167] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for executing all or part of the steps of the methods described in the various embodiments of the present invention through a computer device (which may be a personal computer, a server, or a network device, etc.). The aforementioned storage medium includes: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0168] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calculating the effective coupling length of a cable under HEMP irradiation, characterized in that, include: Based on the cable layout structure of the substation, the target transmission cable is segmented to obtain multiple segments of transmission cable. For each segment of the sub-transmission cable, based on the structural parameters of the sub-transmission cable and using HEMP plane waves as the excitation source, a HEMP coupling simulation model of the sub-transmission cable is constructed. The simulation length of the sub-transmission cable in the HEMP coupling simulation model is gradually increased by a preset length step, and the peak value of the coupling signal response of the HEMP coupling simulation model after being excited by the excitation source is obtained after each increase of the preset length step. Based on the peak value of the coupled signal response after each increase of the preset length step, determine the rate of change of the peak value of the coupled signal response for adjacent preset length steps; If the rate of change of the peak value of the coupled signal response reaches the preset convergence condition, then the latest simulated length of the sub-transmission cable in the HEMP coupling simulation model is determined as the effective coupling length of the sub-transmission cable. The total effective coupling length of the target transmission cable is determined based on the effective coupling length of each segment of the sub-transmission cable.

2. The method for calculating the effective coupling length of cables under HEMP irradiation according to claim 1, characterized in that, The target transmission cable is segmented according to the cable layout structure of the substation to obtain multiple segments of transmission cable, including: Based on the cable routing of the target transmission cable, identify multiple connection turning points of the target transmission cable; The target transmission cable is segmented according to multiple connection turning points to obtain multiple sub-transmission cables.

3. The method for calculating the effective coupling length of cables under HEMP irradiation according to claim 1, characterized in that, The step of constructing a HEMP coupling simulation model of the sub-transmission cable based on its structural parameters and using a HEMP plane wave as the excitation source includes: Based on the structural parameters of the sub-transmission cable, determine the equivalent circuit model parameters of the sub-transmission cable; The excitation parameters of the excitation source are determined based on the electric field strength, magnetic field strength, and incident angle of the HEMP plane wave. Based on the equivalent circuit model parameters and the excitation parameters, an HEMP coupling simulation model of the sub-transmission cable is constructed using electromagnetic simulation software.

4. The method for calculating the effective coupling length of cables under HEMP irradiation according to claim 1, characterized in that, The step of gradually increasing the simulation length of the sub-transmission cable in the HEMP coupling simulation model by a preset length step, and obtaining the peak value of the coupling signal response of the HEMP coupling simulation model after being excited by the excitation source after each increase of the preset length step, includes: Initialize the simulation length of the sub-transmission cable in the HEMP coupled simulation model; The preset length step is obtained, and the simulation length of the sub-transmission cable is gradually increased in units of the preset length step. After each increase, the HEMP coupling simulation model is run to obtain the peak value of the coupling signal response of the preset monitoring point in the HEMP coupling simulation model after being excited by the excitation source. The preset monitoring point is at least located on the shielding layer, armor layer or core wire of the sub-transmission cable.

5. The method for calculating the effective coupling length of a cable under HEMP irradiation according to claim 1 or 4, characterized in that, Also includes: If the rate of change of the peak value of the coupled signal response does not reach the preset convergence condition, then return. The simulation length of the sub-transmission cable in the HEMP coupling simulation model is gradually increased by a preset length step. After each increase of the preset length step, the peak value of the coupling signal response of the HEMP coupling simulation model after being excited by the excitation source is obtained until the rate of change of the peak value of the coupling signal response reaches the preset convergence condition, or the simulation length of the sub-transmission cable reaches the preset maximum length. Then, the latest simulation length of the sub-transmission cable in the HEMP coupling simulation model is output.

6. The method for calculating the effective coupling length of a cable under HEMP irradiation according to claim 1, characterized in that, Also includes: When the target transmission cable has a cable structure consisting of multiple parallel cables, the interference coefficient is determined based on the number of parallel cables and the cable spacing. The effective coupling length of each segment of the sub-transmission cable is corrected according to the interference coefficient to obtain the corrected effective coupling length. Accordingly, determining the total effective coupling length of the target transmission cable based on the effective coupling length of each segment of the sub-transmission cable includes: The total effective coupling length of the target transmission cable is determined based on the corrected effective coupling length of each segment of the sub-transmission cable.

7. A system for calculating the effective coupling length of cables under HEMP irradiation, characterized in that, include: The cable segmentation module is used to segment the target transmission cable according to the cable layout structure of the substation, so as to obtain multiple segments of transmission cable. The simulation model construction module is used to construct a HEMP coupled simulation model of each sub-transmission cable segment based on the structural parameters of the sub-transmission cable and using HEMP plane waves as the excitation source. The coupling signal response module is used to gradually increase the simulation length of the sub-transmission cable in the HEMP coupling simulation model by a preset length step, and to obtain the peak value of the coupling signal response of the HEMP coupling simulation model after being excited by the excitation source after each increase of the preset length step. The peak change analysis module is used to determine the rate of change of the peak value of the coupled signal response for adjacent preset length steps based on the peak value of the coupled signal response after each increase of the preset length step. The effective length determination module is used to determine the latest simulated length of the sub-transmission cable in the HEMP coupling simulation model as the effective coupling length of the sub-transmission cable when the peak change rate of the coupled signal response reaches a preset convergence condition. The total effective length determination module is used to determine the total effective coupling length of the target transmission cable based on the effective coupling length of each segment of the sub-transmission cable.

8. An electronic device, characterized in that, The electronic device includes a memory and a processor. The memory stores a computer program, which, when executed by the processor, causes the processor to perform the steps of the method for calculating the effective coupling length of a cable under HEMP irradiation as described in any one of claims 1-6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed, it implements the steps of the method for calculating the effective coupling length of a cable under HEMP irradiation as described in any one of claims 1-6.

10. A computer program product, characterized in that, The computer program product includes a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, wherein when the program instructions are executed by a computer, the computer performs the steps of the method for calculating the effective coupling length of a cable under HEMP irradiation as described in any one of claims 1-6.

Images