System-level cable electromagnetic pulse effect analysis method and system

Abstract

The invention provides a system-level cable electromagnetic pulse effect analysis method and system, and the method comprises the steps: building a system electromagnetic pulse coupling topological correlation diagram based on a system topological model for the coupling analysis of a cable in a system platform on a strong electromagnetic pulse, and carrying out the analysis of the coupling effect of an independent cable according to the coupling effect analysis of the independent cable and the system topological correlation diagram. On the basis of the independent cables, interaction between the cables is analyzed, and crosstalk coupling between an electromagnetic pulse interference path and the cables is analyzed; and the function of electromagnetic pulse coupling interference analysis from the system level is realized. According to the invention, 8 / 20 [mu] s pulses and 1.2 / 50 [mu] s-8 / 20 [mu] s pulses are used as pulse sources, and the pulse sources have typicality. According to the method, the electromagnetic pulse effect of the independent cables is analyzed, on the basis, crosstalk between the cables is analyzed according to the system topology association diagram, and the analysis of the electromagnetic pulse effect of the cables is more comprehensive.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic protection technology, specifically relating to a system-level cable electromagnetic pulse effect analysis method and system. Background Technology

[0002] In the informationized battlefield, the electromagnetic environment constituted by various electromagnetic hazard sources is very complex. There are radio frequency sources generated by communication equipment such as radio stations and radar, radiation sources caused by electromagnetic pulses from electronic countermeasures, and electromagnetic hazards such as lightning and static electricity in nature, which affect the normal operation of electronic information equipment and may even cause damage to it.

[0003] Electromagnetic pulses (EMPs) can enter electronic information equipment through various coupling pathways. One common coupling method is through cables, where the pulses act on internal electronic components, causing damage. Therefore, studying the EMP effect of cables in a system is crucial for improving the system's resistance to EMP interference and attacks. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a system-level cable electromagnetic pulse effect analysis method and system for performing electromagnetic pulse coupling interference analysis at the system level.

[0005] The technical solution adopted by this invention to solve the above-mentioned technical problems is as follows: a system-level cable electromagnetic pulse effect analysis method, comprising the following steps: S1: Establish an electromagnetic pulse action model that generates impulse current and impulse voltage; S2: Based on electromagnetic topology theory, establish the topological correlation diagram of system-level electromagnetic coupling and the corresponding interference sequence diagram, and determine the coupling response and coupling efficiency of external electromagnetic pulses to the system terminal load; S3: Analyze the electromagnetic pulse effect of independent cables; S4: Analyze the electromagnetic pulse effect of crosstalk in the electrical control unit cables.

[0006] According to the above scheme, the specific steps in step S1 are as follows: S11: Take the 8 / 20μs pulse used to generate the impulse current and the 1.2 / 50μs~8 / 20μs combined wave pulse used to generate the impulse voltage as pulse sources, and establish electromagnetic pulse action models respectively. S12: Draw the 8 / 20μs pulse waveform, with wavefront time T1=1.25×T=8×(1±20%)μs and half-peak time T2=20×(1±20%)μs; Plot the 1.2 / 50μs pulse waveform, with wavefront time T1=1.67×T=1.2×(1±30%)μs and half-peak time T2=50×(1±20%)μs; The 8 / 20μs pulse is characterized by short pulse width, fast rise time, fast fall time, and wide bandwidth. The 1.2 / 50μs pulse is used to generate impulse voltage, featuring high peak voltage, high energy, wide bandwidth, and high repetition frequency.

[0007] Furthermore, in step S11, the operational model using an 8 / 20μs pulse as the pulse source includes a series-connected ideal capacitor C, the total inductance L of the discharge circuit, the total resistance R of the discharge circuit, and a control switch K; assuming... t * To normalize time, ξ The damping coefficient is... T 1 * Let be the wavefront time of the current. i m * Given the peak value of the pulse current; then the normalized current of the pulse current. i * for: (1) The remaining parameters are solved using any one of the parameters R, L, or C.

[0008] Furthermore, in step S11, the action model using the 1.2 / 50μs~8 / 20μs combined wave pulse as the pulse source includes a charging device, an energy storage capacitor C, a tuning inductor L, a discharge switch S, a third tuning resistor R3, a first tuning resistor R1 with one end connected between the tuning inductor L and the discharge switch S and the other end connected to the output terminal of the energy storage capacitor C, and a second tuning resistor R2 connected in parallel between the third tuning resistor R3 and the output terminal of the energy storage capacitor C; In the early stage when the discharge switch S is closed, the energy storage capacitor C charges the tuning inductor L through the second tuning resistor R2 and the third tuning resistor R3, forming the wavefront time T1 of the impulse voltage wave. When the discharge switch S is closed for a relatively long time, the energy storage capacitor C and the tuning inductor L discharge through the first tuning resistor R1, the second tuning resistor R2, and the third tuning resistor R3, forming the half-peak time T2 of the impulse voltage wave. The normalized current is also given by equation (1).

[0009] According to the above scheme, the specific steps in step S2 are as follows: S21: Based on electromagnetic topology theory, establish a topological correlation diagram of system-level electromagnetic pulse coupling, divide the entire system into several sub-regions separated by shielding layers, and decompose the electromagnetic pulse interference to the system into several coupling links. S22: Establish an interference sequence diagram corresponding to the topology association diagram to describe all interference paths from one region to another. Based on the interference sequence diagram, determine the coupling path of external electromagnetic pulses to the system terminal load and the coupling response of all coupling links. S23: Define a transfer function to describe the coupling efficiency of an electromagnetic field from one region to another through a coupling link, or to describe the efficiency of coupling voltage and current in a field in a region on a cable.

[0010] According to the above scheme, the specific steps in step S3 are as follows: S31: Divide the cable into several segments dx much smaller than the operating wavelength λ. Each segment is equivalent to a lumped-parameter circuit, with distributed resistance R, inductance L, capacitance C, and conductance G along the line. Each cable segment exhibits distributed parameter effects. Let the series impedance per unit length be... Z Parallel admittance Y Then the equation for each segment of the parametric circuit is: (3), in: (4); S32: Assuming the cable is straight, the voltage at the beginning is... V 0, the initial current is I 0; Assume the characteristic impedance of each cable segment. Z C Frequency-dependent; propagation constant σ Parameters used to describe the amplitude and phase changes of traveling wave voltage and current; α and β These are the attenuation constant and the phase constant, respectively. Based on the uniform distribution of the distributed parameters along the cable, the general solution of the equation is: (5), in, (6), (7); S33: Assuming the cable is curved, let... V ( x ), I ( x (These are online) x The voltage and current at the point, while curved cables are non-uniform cables. R ( x ), L ( x ), C ( x )and G ( xIt changes as the cable position changes; assuming Z ( x ), Y ( x These are the impedance and admittance per unit length, respectively; according to Kirchhoff's laws, we get: (8), in: (9); Because the cable is curved, the four distributed parameters change with the cable position. x Change; change the characteristic impedance of the bent cable ZC ( x and propagation constant σ ( x ) is represented as: (10) (11); S34: Obtain the current distribution on the cable using the transmission line method, and use the dipole approximation method to solve for the electromagnetic radiation intensity distribution generated by the cable.

[0011] Furthermore, in step S34, the specific steps are as follows: Treating each segment of the cable as a dipole, or as a point... P Suppose a point in space Q Coordinates are ( xq , yq , zq ), PQ and Z The included angle of the axis is γ , PQ and X The included angle of the axis is δ ;set up The phase constant, ω Angular frequency, ε and μ These are the permittivity and permeability of free space, respectively. l The distance is PQ; located at point P electric dipole I ( x ) dx Electromagnetic radiation is generated in space and consists of three vectors: (12); in: (13) (14); Find the current cable position. P Point dipole pairQ The electric field strength generated at the point is: (15).

[0012] According to the above scheme, the specific steps in step S4 are as follows: Regarding crosstalk between cables, let the diameters of the two cables be... d The height from the ground surface is h A single line, the distance between the two lines is D Inductance of wires L for: (16) Mutual inductance between two wires M for: (17) set up V d This is the induced voltage on the disturbed line. L 2 represents the inductance on the second conductor. M The mutual inductance between the two conductors. R d For load, R C For wire harness resistance, f For frequency, i 1 represents the excitation source current; affected by interference line load. R d Voltage amplitude at both ends for: (18).

[0013] A system-level cable electromagnetic pulse effect analysis system The modeling submodule is used to establish electromagnetic pulse action models that generate impulse current and impulse voltage; The coupling analysis submodule is used to establish a topological correlation diagram of system-level electromagnetic coupling and a corresponding interference sequence diagram based on electromagnetic topology theory, and to determine the coupling response and coupling efficiency of external electromagnetic pulses to the system terminal load. Independent cable analysis submodule, used to analyze the electromagnetic pulse effect of independent cables; The cable crosstalk analysis submodule is used to analyze the electromagnetic pulse effect of crosstalk in the electrical control unit cables.

[0014] A computer memory storing a computer program executable by a computer processor, the computer program executing a system-level cable electromagnetic pulse effect analysis method.

[0015] The beneficial effects of this invention are as follows: 1. The present invention provides a system-level cable electromagnetic pulse effect analysis method and system, which is aimed at the coupling analysis of cables to strong electromagnetic pulses in a system platform. Based on the system topology model, a topological correlation diagram of electromagnetic pulse coupling in the system is established. Based on the coupling effect analysis of independent cables and the system topological correlation diagram, the interaction between cables is analyzed on the basis of independent cables, and the electromagnetic pulse interference path and crosstalk coupling between cables are analyzed; thus realizing the function of electromagnetic pulse coupling interference analysis at the system level.

[0016] 2. The present invention uses 8 / 20μs pulses and 1.2 / 50μs-8 / 20μs pulses as pulse sources, and the pulse sources are typical.

[0017] 3. This invention analyzes the electromagnetic pulse effect of independent cables. Based on this, it analyzes the crosstalk between cables according to the system topology diagram, making the electromagnetic pulse effect analysis of cables more comprehensive.

[0018] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0019] 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 some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a flowchart of an embodiment of the present invention.

[0021] Figure 2 This is a diagram of the 8 / 20μs pulse action model according to an embodiment of the present invention.

[0022] Figure 3 This is a circuit diagram for generating 1.2 / 50μs-8 / 20μs pulse impulse voltage according to an embodiment of the present invention.

[0023] Figure 4 This is a circuit diagram for generating 1.2 / 50μs-8 / 20μs pulse short-circuit current according to an embodiment of the present invention.

[0024] Figure 5 This is an 8 / 20μs pulse waveform diagram of an embodiment of the present invention.

[0025] Figure 6 This is a waveform diagram of a 1.2 / 50μs pulse from an embodiment of the present invention.

[0026] Figure 7 This is a system-level platform electromagnetic pulse coupling topology diagram according to an embodiment of the present invention.

[0027] Figure 8 This is a system-level platform electromagnetic pulse coupling interference sequence diagram according to an embodiment of the present invention.

[0028] Figure 9 This is a schematic diagram of crosstalk between wire harnesses according to an embodiment of the present invention.

[0029] Figure 10 This is a schematic diagram of parallel double lines according to an embodiment of the present invention.

[0030] Figure 11 This is the equivalent circuit diagram of parallel double lines in an embodiment of the present invention.

[0031] Figure 12 This is a 3D model diagram of the fully exposed wire harness according to an embodiment of the present invention.

[0032] Figure 13 This is a cross-sectional view of LYFY_1qmm50 according to an embodiment of the present invention.

[0033] Figure 14 This is a 2D model diagram of an unprotected single-core wire circuit according to an embodiment of the present invention.

[0034] Figure 15 This is a schematic diagram of the electromagnetic pulse action direction according to an embodiment of the present invention.

[0035] Figure 16 This is a time-domain waveform diagram of the coupling voltage in an embodiment of the present invention. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0037] Example 1 See Figure 1 The specific steps of a system-level cable electromagnetic pulse effect analysis method are as follows: S1: Establish an electromagnetic pulse action model; S11: Select 8 / 20μs pulse and 1.2 / 50μs~8 / 20μs pulse as pulse sources.

[0038] The action model of the 8 / 20μs pulse is as follows Figure 2 As shown, C is an ideal capacitor; L is the total inductance of the discharge circuit, including gap inductance, wiring inductance, tuning inductance, and load inductance; R is the total resistance of the discharge circuit, including wiring resistance, gap resistance, and tuning resistance; K is the control switch. According to normalization theory, the normalized current of the pulse current is: (1) In the formula, i * For normalized current, t * For normalized time. ξ This is the damping coefficient (attenuation coefficient). The selected parameter is... ξ =0.47、 T 1 * (Current wavefront time) = 0.92 i m * (Peak pulse current) = 0.56. When any one of the parameters R, L, and C is determined, the remaining parameters can be solved.

[0039] The 1.2 / 50μs~8 / 20μs pulse is a combined wave. The circuit consists of a charging device, an energy storage capacitor C, a tuning inductor L, tuning resistors R1, R2, R3, and a discharge switch S. Figure 3 For impulse voltage generation circuit, Figure 4 This is the short-circuit current generation circuit. In the early stages when switch S is closed, capacitor C charges inductor L through resistors R2 and R3, forming the wavefront time T1 of the impulse voltage wave. However, after the switch has been closed for a longer period, capacitor C and inductor L discharge through resistors R1, R2, and R3, forming the half-peak time T2 of the impulse voltage wave. The normalized current is also given by equation (1), taking... ξ =0.5, at this time the corresponding T 1 * =0.917、 i m * =0.55.

[0040] S12: Plot the 8 / 20μs pulse waveform as follows Figure 5 As shown, the wavefront time T1 = 1.25 × T = 8 × (1 ± 20%) μs, and the half-peak time T2 = 20 × (1 ± 20%) μs; the 1.2 / 50 μs pulse waveform is plotted as follows. Figure 6 As shown, the wavefront time T1 = 1.67 × T = 1.2 × (1 ± 30%) μs, and the half-peak time T2 = 50 × (1 ± 20%) μs.

[0041] An 8 / 20μs pulse can generate an inrush current, characterized by a short pulse width, fast rise time, fast fall time, and wide bandwidth. A 1.2 / 50μs pulse can generate an inrush voltage, characterized by high peak voltage, high energy, wide bandwidth, and high repetition frequency. These characteristics lead to the following destructive effects on electronic equipment: (a) The instantaneous coupling effect generates a lot of heat on the circuit and chip of the device. Due to the inability to dissipate heat, the circuit and chip will malfunction and be damaged. (b) The electromagnetic pulse has a wide frequency band and can attack various wireless communication devices through front-door coupling over a wide frequency range. (c) The high-frequency components generated by electromagnetic pulses are the most important coupling factor for wireless communication equipment and other electronic equipment.

[0042] S2: System-level electromagnetic coupling topology analysis; Radiated interference coupling from external electromagnetic pulse system platforms includes the following coupling pathways: (a) Coupling of the external communication antenna on the platform; (b) Radiation field coupled into the cabin space through window openings on the platform hull; (c) Coupling of internal radiation field to interconnecting cables within the cabin; (d) The internal radiation field couples to the openings and gaps in the equipment's shielding housing, and to the secondary radiation coupling of the cables inside the housing.

[0043] The coupling path of electromagnetic pulse coupling interference in the system is complex, with numerous coupling elements and various structural factors. The electromagnetic pulse interference path and the interfered area are intertwined and have a complex relationship. Therefore, system modeling and analysis of the system-level platform are required.

[0044] S21: Based on electromagnetic topology theory, for the system platform, the first step is to establish a topological correlation diagram of the electromagnetic pulse coupling of the entire system, such as... Figure 7 As shown, the entire system is divided into several sub-regions, which are separated by shielding layers, thus decomposing the electromagnetic pulse interference to the entire system into several coupled links. In the topology diagram, the regions and coupled links follow the following naming rules: (a) Each region is represented by V, V i.j V0 represents the j-th sub-region within the i-th shielding layer, and the external region of the entire system is represented by V0. (b) Each shielding layer of the system is denoted by S, S i.j:k.h This indicates that region V i.j and V k.h In general, as the subscript of the separated shielding layer increases, the higher the shielding level, the less the coupling interference of external electromagnetic interference to this area. (c) Indicates a cable connector. This refers to the terminal device.

[0045] In the picture: (a)S 0:1.1 This indicates the shielded enclosure structure of the system, which separates the external area V0 from the internal area V1.1. (b)S 1.1:2.1 This indicates the shielding layer structure of the shielded cable in the antenna feeder system, S1.1:2.2 This refers to the shielding housing of the terminal equipment connecting the shielded cable of the antenna feeder system, and the V-shaped internal area of ​​the shielded cable. 2.1 and the internal area of ​​the shielding housing of the terminal equipment V 2.2 Separated by cable connector structure (dashed line). Other antenna system shielding layer S 1.1:2.3 ~S 1.1:2.10 They have similar definitions; (c)S 1.1:2.11 The shielding housings of terminal devices 6 and 7 for interconnecting cables with S=; (d)S 1.1:2.13 The shielding shell for the perforated equipment 8 inside the cabin.

[0046] S22: After establishing the system's topology graph, in order to describe all interference paths from one region to another and determine coupling links, it is necessary to establish an interference sequence graph corresponding to the topology graph, such as... Figure 8 The diagram shows the interference sequence of electromagnetic pulse coupling on a system-level platform. In the diagram, For spatial sub-regions, Represents the equipment's shielding housing. Represents the cable shielding layer. For external receiving antenna, This represents the coupling from the field to the line. For terminal load, "- -" represents the interference coupling path between different subdomains.

[0047] Based on the above interference sequence diagram, the coupling path and coupling links of the external electromagnetic pulse to the entire system terminal can be clearly seen: (a) For the antenna feeder system, the external region electromagnetic pulse V0 first causes interference coupling through the receiving antenna, and is coupled to the terminal load by conduction; secondly, the electromagnetic pulse passes through the system platform cabin S 0:1.1 Entering the interior space V 1.1 and through the cable shielding layer S 1.1:2.1 and the equipment shielding housing S 1.1:2.2 Causes interference coupling into region V 2.1 and V 2.2 This results in a combined effect on the system's terminal load. Since antenna feeder systems 1-5 share the same coupling path, therefore... Figure 8 Other antenna interference sequences have been omitted; (b) For interconnecting devices 6 and 7, external electromagnetic pulses are transmitted through platform housing S. 0:1.1 Entering the interior space V 1.1 And through the direct coupling effect of the internal radiation field on the cable, it causes interference coupling to the terminal; (c) For device 8, the external electromagnetic pulse first enters the cabin S. 0:1.1Internal space V 1.1 Through the shielding housing S of device 8 1.1:2.13 The pores and seams enter the internal region of the cavity V 2.13 Finally, the electromagnetic pulse interferes with the terminal load through the coupling effect of the field on the cable. To solve the coupling response of the external electromagnetic pulse to the terminal load, it is necessary to solve the coupling response of all coupling links in each coupling path.

[0048] S23: Define a transfer function to describe the coupling efficiency of an electromagnetic field from one region to another through a coupling element, or to describe the efficiency of coupling voltage and current of a field in one region onto a cable. For example, the transfer function for the voltage and current coupled from an external electromagnetic pulse through an antenna to the feed port can be expressed as: (2) S3: Electromagnetic pulse effect analysis of independent cables; Cables are the carriers of electrical energy and signals, and are the foundation for the operation of all electrical and electronic equipment. Theory and engineering practice show that most systems that fail to meet electromagnetic compatibility standards or cause electromagnetic interference to surrounding electrical equipment can be attributed to electromagnetic radiation generated by cables. This embodiment's analysis of the electromagnetic pulse effect of cables mainly focuses on spatial electromagnetic radiation interference, specifically in the following two aspects: (a) Cables are electromagnetic radiation transmitting antennas. As the total power of the system increases, the more electromagnetic energy is radiated by the cables, and the more prominent the electromagnetic interference problem becomes.

[0049] (b) Cables are electromagnetic radiation receiving antennas and are very sensitive to electromagnetic radiation. Electromagnetic radiation in the space around the cable can directly act on the cable through field line coupling and then enter the sensitive equipment through the cable, affecting the normal operation of the sensitive equipment. S31: Divide the cable into several segments, each of which is sufficiently short, with a length much smaller than the operating wavelength. This is represented by dx, i.e., dx λ. At this point, each segment is represented by four parameters: resistance R, inductance L, capacitance C, and conductance G, and is treated as a lumped parameter circuit. Because these four parameters are distributed along the line, each cable segment exhibits distributed parameter effects.

[0050] The equations for each segment of the parametric circuit can be obtained: (3) in: (4) Z and Y These represent the series impedance and parallel admittance per unit length, respectively.

[0051] S32: Assuming the cable is straight, the voltage at the beginning is... V 0 and the initial current are I 0. Based on the law that the distribution parameters are uniformly distributed along the cable, i.e., a uniform cable, the general solution of the equation can be obtained as: (5) in, (6) (7) in, Z C This represents the characteristic impedance of each cable segment, which is frequency-dependent and measured in Ω / m. σ The propagation constant is a parameter that describes the amplitude and phase changes of traveling wave voltage and current. α and β These are the attenuation constant and the phase constant, respectively. S33: Assuming the cable is curved, let... V ( x ), I ( x (These are online) x The voltage and current at the point, while curved cables are non-uniform cables. R ( x ), L ( x ), C ( x )and G ( x The values ​​will change depending on the cable's position. Due to this characteristic, we can only deduce the following from Kirchhoff's laws: (8) in: (9) In the formula, Z ( x ), Y ( x These represent the impedance and admittance per unit length, respectively. Since the cable is curved, the four distributed parameters vary with the cable's position. x And thus, the characteristic impedance of the bent cable changes. ZC ( x and propagation constant σ ( x This can be represented as: (10) (11) S34: The current distribution on the cable has been obtained using the transmission line method. The electromagnetic radiation intensity distribution generated by the cable is solved using the dipole approximation method. As mentioned above, the cable is divided into several segments, each of which can be considered as a dipole, or a point. P Suppose a point in space Q Coordinates are ( xq , yq , zq ), PQ and Z The included angle of the axis is γ , PQ and X The included angle of the axis is δ Located at point P electric dipole I ( x ) dx Electromagnetic radiation is generated in space and consists of three vectors: (12) In the formula, The phase constant, ω Angular frequency, ε and μ These are the permittivity and permeability of free space, respectively. l Let P be the distance between P and Q. (13) (14) We can calculate the current cable position at this time. P Point dipole pair Q The electric field strength generated at the point is: (15) S4: Electromagnetic pulse effect analysis of crosstalk in electrical control unit cables; Regarding crosstalk between cables, let the diameters of the two cables be... d The height from the ground is h A single line, the distance between the two lines is D A schematic diagram of crosstalk between wire harnesses is shown below. Figure 9 As shown.

[0052] Inductance of wires L As shown in the following formula: (16) Mutual inductance between two wires M As shown in the following formula: (17) The schematic diagram of parallel double lines is as follows Figure 10 As shown, the equivalent circuit diagram is as follows: Figure 11 As shown.

[0053] Interference-affected line load R d The voltage amplitude at both ends is shown in the following formula.

[0054] (18) in, V d This is the induced voltage on the disturbed line. L 2 represents the inductance on wire 2. M The mutual inductance between the two conductors. R d For load, R C For wire harness resistance, f For frequency, i 1 represents the excitation source current.

[0055] This embodiment focuses on the coupling analysis of cables to strong electromagnetic pulses in a system platform. Based on the system topology model, a topological correlation diagram of electromagnetic pulse coupling in the system is established. Based on the coupling analysis of independent cables and the system topological correlation diagram, the interaction between cables is analyzed on the basis of independent cables, and the electromagnetic pulse interference path and crosstalk coupling between cables are analyzed; thus realizing the function of electromagnetic pulse coupling interference analysis at the system level.

[0056] Example 2 The steps in this embodiment are the same as in Embodiment 1, except that each step is applied to a specific instance. Specifically, it includes the following steps: The peak-to-peak value of the coupling voltage of a wire harness and wire harness group with 80% braid density under electromagnetic pulse was simulated and analyzed to obtain the variation law of the peak-to-peak value of the coupling voltage of the wire harness and wire harness group. First, a 100cm*150cm plate was built in the CST Cable Studio simulation software. The plate was grounded to simulate the earth (the size of the plate is larger than the size of the wire harness model). The material of the plate was set as an ideal conductor (PEC). Next, a single-core wire model with a length of 1m and a wire type of LYFY_1qmm50 was built 10cm above the plate. The 3D model of the fully exposed wire harness and its cross-section are shown in the figure. Figure 12 , Figure 13 As shown.

[0057] A cable termination load circuit model was created using CST Cable Studio. Both ends of the model were connected to 50Ω resistors and then grounded. Probes P1 and P2 were added to both ends respectively. The circuit model is as follows: Figure 14 As shown.

[0058] The electromagnetic pulse selected is an 8 / 20μs pulse, with its direction of action perpendicular to the cable direction. The electromagnetic pulse wave adopts linear polarization, such as... Figure 15 As shown.

[0059] The peak-to-peak time-domain waveform of the coupling voltage of a 1m fully exposed wire harness under an 8 / 20μs pulse is as follows: Figure 16 As shown, the values ​​of probe P1 and probe P2 are the same, both 160V. This is because the probes are symmetrically placed at both ends of the fully exposed wire harness, and the coupling voltage at these two ends is the same. Therefore, the peak-to-peak value of the coupling voltage on the cable is 160V, which is consistent with the actual result, proving the accuracy of the method in this embodiment.

[0060] This embodiment uses 8 / 20μs pulses and 1.2 / 50μs-8 / 20μs pulses as pulse sources, which are typical. This embodiment analyzes the electromagnetic pulse effect of independent cables. Based on this, crosstalk between cables is analyzed according to the system topology diagram, making the electromagnetic pulse effect analysis of cables more comprehensive.

[0061] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0062] Example 3 This embodiment is used to implement the principle of the above method embodiment to construct a system-level cable electromagnetic pulse effect analysis system, including a modeling submodule, a coupling analysis submodule, an independent cable analysis submodule, and a cable crosstalk analysis submodule; The modeling submodule is used to establish electromagnetic pulse action models that generate impulse current and impulse voltage; The coupling analysis submodule is used to establish a topological correlation diagram of system-level electromagnetic coupling and a corresponding interference sequence diagram based on electromagnetic topology theory, and to determine the coupling response and coupling efficiency of external electromagnetic pulses to the system terminal load. Independent cable analysis submodule, used to analyze the electromagnetic pulse effect of independent cables; The cable crosstalk analysis submodule is used to analyze the electromagnetic pulse effect of crosstalk in the electrical control unit cables.

[0063] Each submodule is mainly used to implement the various steps of the method embodiment, which will not be elaborated here.

[0064] It should be noted that, depending on the implementation needs, the various steps / components described in this application can be broken down into more steps / components, or two or more steps / components or parts of the operation of steps / components can be combined into new steps / components to achieve the purpose of this invention.

[0065] This embodiment also includes a processor, a communication interface, a memory, and a communication bus; wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; the memory stores a computer program, and when the program is executed by the processor, the processor performs the steps of a system-level cable electromagnetic pulse effect analysis method.

[0066] This embodiment also provides a computer-readable storage medium storing executable instructions that, when executed by a processor, enable the processor to implement a system-level cable electromagnetic pulse effect analysis method.

[0067] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects.

[0068] Furthermore, this application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0069] This application is described with reference to the flowchart of the method and computer program product according to Embodiment 1 and the block diagram of the device (system) according to Embodiment 3. It should be understood that each step or block in the flowchart or block diagram, as well as combinations of steps or blocks in the flowchart or block diagram, can be implemented by computer program instructions.

[0070] These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions, which are executable by the processor of the computer or other programmable data processing device, produce instructions for implementing the process. Figure 1 One or more processes or boxes Figure 1 A system-level cable electromagnetic pulse effect analysis system that specifies the functions in one or more boxes.

[0071] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes or boxes Figure 1 The function specified in one or more boxes.

[0072] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes or boxes Figure 1 The steps of a system-level cable electromagnetic pulse effect analysis method are specified in one or more boxes.

[0073] The above embodiments are only used to illustrate the design concept and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. The protection scope of the present invention is not limited to the above embodiments. Therefore, all equivalent changes or modifications made based on the principles and design ideas disclosed in the present invention are within the protection scope of the present invention.

Claims

1. A system-level cable electromagnetic pulse effect analysis method, characterized in that: Includes the following steps: S1: Establish an electromagnetic pulse action model that generates impulse current and impulse voltage; S2: Based on electromagnetic topology theory, establish the topological correlation diagram of system-level electromagnetic coupling and the corresponding interference sequence diagram, and determine the coupling response and coupling efficiency of external electromagnetic pulses to the system terminal load; S3: Analyze the electromagnetic pulse effect of independent cables; S4: Analyze the electromagnetic pulse effect of crosstalk in the electrical control unit cables.

2. The system-level cable electromagnetic pulse effect analysis method according to claim 1, characterized in that: The specific steps in step S1 are as follows: S11: Take the 8 / 20μs pulse used to generate the impulse current and the 1.2 / 50μs~8 / 20μs combined wave pulse used to generate the impulse voltage as pulse sources, and establish electromagnetic pulse action models respectively. S12: Draw the 8 / 20μs pulse waveform, with wavefront time T1=1.25×T=8×(1±20%)μs and half-peak time T2=20×(1±20%)μs; Plot the 1.2 / 50μs pulse waveform, with wavefront time T1=1.67×T=1.2×(1±30%)μs and half-peak time T2=50×(1±20%)μs; The 8 / 20μs pulse is characterized by short pulse width, fast rise time, fast fall time, and wide bandwidth. The 1.2 / 50μs pulse is used to generate impulse voltage, featuring high peak voltage, high energy, wide bandwidth, and high repetition frequency.

3. The method for analyzing electromagnetic pulse effects in system-level cables according to claim 2, characterized in that: In step S11, the operational model using an 8 / 20μs pulse as the pulse source includes an ideal capacitor C connected in series, the total inductance L of the discharge circuit, the total resistance R of the discharge circuit, and a control switch K; assuming... t * To normalize time, ξ The damping coefficient is... T 1 * Let be the wavefront time of the current. i m * Given the peak value of the pulse current; then the normalized current of the pulse current. i * for: （1） The remaining parameters are solved using any one of the parameters R, L, or C.

4. The system-level cable electromagnetic pulse effect analysis method according to claim 3, characterized in that: In step S11, the action model using the 1.2 / 50μs~8 / 20μs combined wave pulse as the pulse source includes a series charging device, an energy storage capacitor C, a tuning inductor L, a discharge switch S, a third tuning resistor R3, a first tuning resistor R1 with one end connected between the tuning inductor L and the discharge switch S and the other end connected to the output terminal of the energy storage capacitor C, and a second tuning resistor R2 connected in parallel between the third tuning resistor R3 and the output terminal of the energy storage capacitor C. In the early stage when the discharge switch S is closed, the energy storage capacitor C charges the tuning inductor L through the second tuning resistor R2 and the third tuning resistor R3, forming the wavefront time T1 of the impulse voltage wave. When the discharge switch S is closed for a relatively long time, the energy storage capacitor C and the tuning inductor L discharge through the first tuning resistor R1, the second tuning resistor R2, and the third tuning resistor R3, forming the half-peak time T2 of the impulse voltage wave. The normalized current is also given by equation (1).

5. The system-level cable electromagnetic pulse effect analysis method according to claim 1, characterized in that: The specific steps in step S2 are as follows: S21: Based on electromagnetic topology theory, establish a topological correlation diagram of system-level electromagnetic pulse coupling, divide the entire system into several sub-regions separated by shielding layers, and decompose the electromagnetic pulse interference to the system into several coupling links. S22: Establish an interference sequence diagram corresponding to the topology association diagram to describe all interference paths from one region to another. Based on the interference sequence diagram, determine the coupling path of external electromagnetic pulses to the system terminal load and the coupling response of all coupling links. S23: Define a transfer function to describe the coupling efficiency of an electromagnetic field from one region to another through a coupling link, or to describe the efficiency of coupling voltage and current in a field in a region on a cable.

6. The method for analyzing electromagnetic pulse effects in system-level cables according to claim 1, characterized in that: The specific steps in step S3 are as follows: S31: Divide the cable into several segments dx much smaller than the operating wavelength λ. Each segment is equivalent to a lumped-parameter circuit, with distributed resistance R, inductance L, capacitance C, and conductance G along the line. Each cable segment exhibits distributed parameter effects. Let the series impedance per unit length be... Z Parallel admittance Y Then the equation for each segment of the parametric circuit is: （3）， in: （4）； S32: Assuming the cable is straight, the voltage at the beginning is... V 0, the initial current is I 0; Assume the characteristic impedance of each cable segment. Z C Frequency-dependent; propagation constant σ Parameters used to describe the amplitude and phase changes of traveling wave voltage and current; α and β These are the attenuation constant and the phase constant, respectively. Based on the uniform distribution of the distributed parameters along the cable, the general solution of the equation is: （5）， in, （6）， （7）； S33: Assuming the cable is curved, let... V ( x ), I ( x (These are online) x The voltage and current at the point, while curved cables are non-uniform cables. R ( x ), L ( x ), C ( x )and G ( x It changes as the cable position changes; assuming Z ( x ), Y ( x These are the impedance and admittance per unit length, respectively; according to Kirchhoff's laws, we get: （8）， in: （9）； Because the cable is curved, the four distributed parameters vary with the cable position. x Change; change the characteristic impedance of the bent cable ZC ( x and propagation constant σ ( x ) is represented as: （10）， （11）； S34: Obtain the current distribution on the cable using the transmission line method, and use the dipole approximation method to solve for the electromagnetic radiation intensity distribution generated by the cable.

7. The method for analyzing electromagnetic pulse effects in system-level cables according to claim 6, characterized in that: The specific steps in step S34 are as follows: Treating each segment of the cable as a dipole, or as a point... P Suppose a point in space Q Coordinates are ( xq , yq , zq ), PQ and Z The included angle of the axis is γ , PQ and X The included angle of the axis is δ ;set up The phase constant, ω Angular frequency, ε and μ These are the permittivity and permeability of free space, respectively. l The distance is PQ; located at point P electric dipole I ( x ) dx Electromagnetic radiation is generated in space and consists of three vectors: （12）； in: （13）， （14）； Find the current cable position. P Point dipole pair Q The electric field strength generated at the point is: （15）。 8. The system-level cable electromagnetic pulse effect analysis method according to claim 1, characterized in that: The specific steps in step S4 are as follows: Regarding crosstalk between cables, let the diameters of the two cables be... d The height from the ground surface is h A single line, the distance between the two lines is D Inductance of wires L for: （16）， Mutual inductance between two wires M for: （17）， set up V d This is the induced voltage on the disturbed line. L 2 represents the inductance on the second conductor. M The mutual inductance between the two conductors. R d For load, R C For wire harness resistance, f For frequency, i 1 represents the excitation source current; affected by interference line load. R d Voltage amplitude at both ends for: （18）。 9. A system-level cable electromagnetic pulse effect analysis system, characterized in that: The modeling submodule is used to establish electromagnetic pulse action models that generate impulse current and impulse voltage; The coupling analysis submodule is used to establish a topological correlation diagram of system-level electromagnetic coupling and a corresponding interference sequence diagram based on electromagnetic topology theory, and to determine the coupling response and coupling efficiency of external electromagnetic pulses to the system terminal load. Independent cable analysis submodule, used to analyze the electromagnetic pulse effect of independent cables; The cable crosstalk analysis submodule is used to analyze the electromagnetic pulse effect of crosstalk in the electrical control unit cables.

10. A computer memory, characterized in that: It contains a computer program that can be executed by a computer processor, which performs a system-level cable electromagnetic pulse effect analysis method as described in any one of claims 1 to 8.

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