New energy high-frequency wire harness design method based on electromagnetic compatibility optimization

Abstract

The invention aims to provide a new energy high-frequency wire harness design method based on electromagnetic compatibility optimization, and relates to the technical field of new energy, and the method comprises the steps: 1, building a new energy high-frequency wire harness type electromagnetic source model, and obtaining the electromagnetic source intensity; calculating a spatial electromagnetic field intensity based on the electromagnetic source intensity; step 2, calculating equivalent transmission line parameters based on the space electromagnetic field intensity; based on the equivalent transmission line parameters, frequency-dependent characteristic impedance is calculated; step 3, calculating crosstalk voltage according to the frequency-variable characteristic impedance; calculating a radiation field of the new energy high-frequency wire harness; calculating the shielding effectiveness of the new energy high-frequency wire harness according to the radiation field; 4, according to the step 1, the step 2 and the step 3, constraint conditions are set, an objective function under the constraint conditions is established, and the objective function is solved through iteration to find the corresponding optimal design parameter vector of the new energy high-frequency wire harness. According to the invention, the transmission stability and the anti-interference capability of the new energy high-frequency wire harness are significantly improved.

Description

Technical Field

[0001] The present invention relates to the field of new energy technology, and in particular to a new energy high-frequency wiring harness design method based on electromagnetic compatibility optimization. Background Art

[0002] In the field of modern new energy applications, especially in the context of the rapid development of new energy vehicles and high-frequency signal transmission systems, the electromagnetic compatibility (EMC) problem of new energy high-frequency wiring harnesses is particularly important. During the transmission of high-frequency signals, electromagnetic interference will cause problems such as signal crosstalk and radiation interference, which will in turn affect the transmission quality and reliability of the system. With the increase of high-frequency equipment such as high-frequency current drive systems and communication modules in new energy vehicles, the problem of electromagnetic interference transmitted in the wiring harness system has become more and more complicated. The existing technology has proposed a variety of design methods for dealing with high-frequency electromagnetic interference, but there are still many technical difficulties and problems to be solved.

[0003] First, the prior art mostly uses shielding materials for high-frequency electromagnetic interference control, but the shielding effectiveness of shielding materials under high-frequency currents is not stable. Typical electromagnetic shielding designs use metal materials to cover the wiring harness, and the reflection and absorption of electromagnetic interference are achieved through the conductive properties of the metal materials. However, the higher the frequency, the stronger the penetration of electromagnetic waves, and the effectiveness of traditional metal shielding layers under high-frequency conditions gradually decreases. In particular, under the influence of the skin effect, the current is concentrated on the surface of the shielding material rather than flowing inside, which leads to a significant increase in the influence of the thickness of the shielding layer on the shielding effect at extremely high frequencies. Due to this characteristic, how to design a shielding layer with a higher attenuation effect while ensuring high-frequency shielding effectiveness is still a difficulty in the prior art. In addition, traditional shielding material designs usually only consider electromagnetic interference in a single frequency band or a narrow frequency band, and cannot provide stable shielding effectiveness over a wider frequency range. Secondly, the prior art usually relies on reasonable wiring harness arrangement and distance control in terms of crosstalk control. The distance between adjacent wiring harnesses is one of the key factors affecting the crosstalk voltage. By increasing the spacing between wiring harnesses, the electromagnetic coupling strength between each other can be reduced to a certain extent. However, in new energy vehicles, the number of wiring harnesses is huge and the space is limited, and the spacing control between the wiring harnesses is limited, resulting in the inability to effectively reduce crosstalk by increasing the spacing in some designs. In addition, during high-frequency signal transmission, the electromagnetic coupling phenomenon is more serious than in low-frequency conditions, and the rapidly changing components in the signal produce strong transient voltages in adjacent wiring harnesses. This transient interference not only affects the quality of signal transmission, but also reduces the stability of the entire system. Although the prior art has attempted to adopt a multi-layer shielding design to enhance the anti-crosstalk capability, such a solution increases the complexity and cost of the system, and has limited effect outside a certain frequency range. Summary of the invention

[0004] In view of this, the main purpose of the present invention is to provide a new energy high-frequency wire harness design method based on electromagnetic compatibility optimization, which realizes the precise control of electromagnetic interference of new energy high-frequency wire harnesses in complex electromagnetic environments. This method globally optimizes the objective function, so that the new energy high-frequency wire harness maintains low radiation, low crosstalk and high shielding effectiveness under high frequency conditions, significantly improving the transmission stability and anti-interference ability of the new energy high-frequency wire harness.

[0005] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0006] A new energy high-frequency wiring harness design method based on electromagnetic compatibility optimization, the method comprising:

[0007] Step 1: Establish an electromagnetic source model of the new energy high-frequency wire harness, and obtain the electromagnetic source intensity of the new energy high-frequency wire harness at each spatial point; based on the electromagnetic source intensity, calculate the electromagnetic field intensity in space;

[0008] Step 2: Based on the spatial electromagnetic field intensity, calculate the equivalent transmission line parameters of the new energy high-frequency wire harness; based on the equivalent transmission line parameters, calculate the frequency-dependent characteristic impedance of the new energy high-frequency wire harness;

[0009] Step 3: According to the frequency-dependent characteristic impedance, the crosstalk between adjacent wire harnesses in the new energy high-frequency wire harness is analyzed and the crosstalk voltage is calculated; according to the crosstalk voltage, the radiation field of the new energy high-frequency wire harness is calculated; according to the radiation field, the shielding effectiveness of the new energy high-frequency wire harness is calculated;

[0010] Step 4: According to step 1, step 2 and step 3, set constraints, and establish an objective function under the constraints, and iteratively solve the objective function to find the optimal design parameter vector of the corresponding new energy high-frequency wiring harness; design the new energy high-frequency wiring harness through the optimal design parameter vector; the elements of the optimal design parameter vector include: the number of current sources, frequency-variable resistance, frequency-variable inductance, frequency-variable capacitance, frequency-variable conductance, shielding layer thickness and wiring harness current of the new energy high-frequency wiring harness.

[0011] Furthermore, in step 1, the electromagnetic source model of the new energy high-frequency wire beam is established by the following formula to obtain the electromagnetic source intensity of the new energy high-frequency wire beam at each spatial point:

[0012]

[0013] Where S(r,ω) represents the electromagnetic source intensity at a spatial point r at a given frequency ω; N is the number of current sources in the new energy high-frequency wire harness; i is an integer subscript index; I i is the current intensity of the i-th current source; is the attenuation factor of the current source intensity during spatial propagation, which simulates the inverse square attenuation characteristic of the distance from the current source to the spatial point; ri is the position vector of the i-th current source; t is the time variable; j is the negative sign; Represents the magnetization intensity M i (r) is the curl operation term; M i (r) is the magnetization at the i-th current source, is the curl operator and represents the effect of the magnetic field generated by the current source on the magnetization of the surrounding area.

[0014] Furthermore, in step 1, the electromagnetic field strength in space is calculated based on the electromagnetic source strength by the following formula:

[0015]

[0016] Where E(r,ω) represents the electromagnetic field intensity at a given frequency ω at a spatial point r; the skin depth δ(ω) defines the penetration depth of the electric field in the medium at the frequency ω; r' is the position integral variable;

[0017] G(r,r') is the corresponding propagation Green's function under the position integral variable; S(r',ω) is the corresponding form of S(r,ω) under the position integral variable; V is the spatial range of the new energy high-frequency harness.

[0018] Furthermore, in step 2, the equivalent transmission line parameters of the new energy high-frequency wire harness are calculated based on the spatial electromagnetic field intensity by the following formula:

[0019]

[0020] in, is the equivalent transmission line parameter of the new energy high-frequency wiring harness; R(ω) is the frequency-dependent resistance at a given frequency ω; |E(r,ω)| is the modulus of the electric field intensity; σ c is the conductivity of the conductor of the new energy high-frequency wiring harness; C represents the closed path around the new energy high-frequency wiring harness; dl represents the distance integral variable on the closed path around the new energy high-frequency wiring harness; L(ω) is the frequency-variable inductance at a given frequency ω; μ0 is the vacuum permeability; d max is the diameter of the outer conductor of the new energy high-frequency wiring harness; d min is the diameter of the inner conductor of the new energy high-frequency wiring harness; μ r is the relative magnetic permeability of the new energy high-frequency wire harness, which indicates the magnetic permeability of the material of the new energy high-frequency wire harness relative to vacuum; ε r is the relative dielectric constant of the new energy high-frequency wire harness, which indicates the capacitance characteristics of the material of the new energy high-frequency wire harness relative to vacuum; ε0 is the dielectric constant of vacuum; C(ω) is the frequency-variable capacitance at a given frequency ω; G(ω) is the frequency-variable conductance at a given frequency ω; σ d is the conductivity of the medium.

[0021] Furthermore, in step 2, the frequency-dependent characteristic impedance of the new energy high-frequency wiring harness is calculated based on the equivalent transmission line parameters by the following formula:

[0022]

[0023] Among them, Z c (ω) is the frequency-dependent characteristic impedance at a given frequency ω; γ(ω) is the propagation constant at a given frequency ω; X is the length of the new energy high-frequency wiring harness.

[0024] Furthermore, in step 3, the crosstalk between adjacent wiring harnesses in the new energy high-frequency wiring harness is analyzed and the crosstalk voltage is calculated according to the frequency-dependent characteristic impedance using the following formula:

[0025]

[0026] Where Z0 is the nominal characteristic impedance; M 12 (ω) is the mutual inductance coefficient, which indicates the degree of electromagnetic coupling between two wire bundles. It is the mutual inductance of adjacent wire bundles at frequency ω; V xt (r,ω) is the crosstalk voltage at the spatial point r at a given frequency ω.

[0027] Furthermore, in step 3, the radiation field of the new energy high-frequency wiring harness is calculated according to the crosstalk voltage using the following formula:

[0028]

[0029] Among them, E rad (r,ω) represents the radiation field at the spatial point r at a given frequency ω after the shielding layer is installed; k is the wave number; k is the wave vector.

[0030] Furthermore, in step 3, the shielding effectiveness of the new energy high-frequency wiring harness is calculated based on the radiation field using the following formula:

[0031]

[0032] Among them, D is the thickness of the shielding layer of the new energy high-frequency wire harness; SE(ω) is the shielding effectiveness at frequency ω, in decibels; E0(r,ω) is the radiation field at the spatial point r at frequency ω when there is no shielding; α(ω) represents the attenuation constant at frequency ω, which determines the absorption intensity of the shielding layer to electromagnetic waves and is the set value.

[0033] Furthermore, in step 4, the constraint conditions are set by the following formula:

[0034] |E rad (r,ω)| <E lim ;

[0035] |V xt (z,ω)| <V lim ;

[0036] SE(ω)>SE min ;

[0037] |Z c (ω)-Z0|<ΔZ max ;

[0038] Among them, E lim is the set radiation limit; V lim is the set crosstalk limit; SE ref is the target shielding effectiveness; ΔZ max is the characteristic impedance threshold set; the objective function is defined as:

[0039]

[0040] min{EMC total};

[0041] Among them, EMC total is the performance index; ω1 is the set frequency lower limit; ω2 is the set frequency upper limit.

[0042] By adopting the above technical scheme, the present invention has the following intentional effects: the present invention accurately calculates the electromagnetic source intensity of each spatial point through a distributed electromagnetic source model, thereby realizing a comprehensive analysis of the electromagnetic field distribution in the high-frequency harness system. The traditional harness electromagnetic interference calculation method usually ignores the distribution characteristics of the current source in space, while the present invention adds the distribution calculation of the electromagnetic source intensity to the modeling of the high-frequency signal. Such a distributed modeling method can effectively capture the electromagnetic field changes of the high-frequency electromagnetic signal at different spatial points. On this basis, through further field intensity calculation and equivalent transmission line parameter extraction, the present invention realizes an accurate description of the electromagnetic field intensity under different frequency conditions, thereby providing more accurate electromagnetic interference evaluation data. This sophisticated electromagnetic source modeling method improves the accuracy of electromagnetic compatibility design, allowing designers to more accurately control and optimize electromagnetic interference characteristics in practical applications. Secondly, the present invention accurately evaluates the propagation characteristics of electromagnetic interference by calculating the frequency-dependent characteristic impedance, crosstalk voltage and radiation field, and effectively controls the attenuation and interference of the signal under high-frequency conditions. The calculation of the frequency-dependent characteristic impedance can track the impedance changes of the harness in real time at different frequencies, so that the transmission impedance of the high-frequency harness system can remain stable within a wide frequency band. Impedance matching is crucial to reducing signal reflection and transmission loss. The present invention effectively reduces the reflection loss of high-frequency signals during transmission and improves transmission efficiency through dynamic impedance calculation and optimization. This impedance optimization strategy can significantly reduce the power loss of signals in practical applications, ensuring that the system still maintains high transmission quality and stability in complex frequency environments. In terms of crosstalk suppression, the present invention introduces the calculation of crosstalk voltage, and realizes effective control of crosstalk between adjacent harnesses through comprehensive analysis of factors such as frequency-dependent characteristic impedance, mutual inductance coefficient, and current change rate. Traditional crosstalk control methods mostly rely on increasing harness spacing or using multi-layer shielding. The present invention combines current source changes, harness characteristics, and electromagnetic coupling strength for comprehensive evaluation through precise crosstalk voltage calculation, thereby achieving more efficient anti-crosstalk capability without significantly increasing system complexity. Especially under high-frequency conditions, due to the enhanced electromagnetic coupling strength, the method of the present invention can effectively reduce electromagnetic interference between adjacent harnesses, thereby improving the anti-interference performance of the signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0044] Figure 1 A schematic diagram of a method flow of a new energy high-frequency wiring harness design method based on electromagnetic compatibility optimization provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0045] The method of the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments of the present invention.

[0046] Example 1: Reference Figure 1 , a new energy high-frequency wiring harness design method based on electromagnetic compatibility optimization, the method comprising:

[0047] Step 1: Establish an electromagnetic source model of the new energy high-frequency wire harness, and obtain the electromagnetic source intensity of the new energy high-frequency wire harness at each spatial point; based on the electromagnetic source intensity, calculate the electromagnetic field intensity in space;

[0048] Since new energy equipment often operates under high frequency conditions, the wiring harness system inside it generates strong electromagnetic interference, and these interferences will become more complex and difficult to control as the frequency increases. The electromagnetic source distribution of the high-frequency wiring harness has significant spatial and frequency dependence. Therefore, designing an electromagnetic source model that can accurately reflect the distribution characteristics of the electromagnetic field becomes the basis for optimization design. The present invention takes into account the spatial position, frequency characteristics and mutual coupling relationship of each current source in the high-frequency wiring harness by establishing a distributed electromagnetic source model, so that the electromagnetic source intensity at each position can be accurately expressed. The construction process of the electromagnetic source model is based on the mathematical expression of each current source, so that the contribution of the current source to the electromagnetic field in space can be described by parameters such as source point position, frequency, amplitude and phase. In actual high-frequency wiring harnesses, different current sources are located at different spatial positions, and these current sources are not only excited at a specific frequency, but also interfere with each other due to various factors such as spatial distance and conductor medium. Therefore, in order to accurately describe the electromagnetic source intensity of the current source in space, the model of the present invention introduces the spatial distance factor between the source and the field, so that the electromagnetic field contribution of each current source gradually decays as the distance from the source point to the field point increases, which conforms to the inverse square law of electromagnetic radiation. At the same time, by combining the frequency components of each current source, the model can accurately reflect the dynamic changes caused by the high-frequency current source. This dynamic change includes the phase change in time, and the phase term in complex form is used to describe the evolution of the phase at different frequencies, thereby reflecting the fluctuation characteristics of the high-frequency current source in the time domain in the model.

[0049] In this electromagnetic source model, the spatial distribution and mutual coupling of multiple current sources are described by the superposition principle, which enables the model to capture the composite field effect of current sources in high-frequency wire bundles. Specifically, the electromagnetic source model regards each current source as an independent point source, and calculates the electromagnetic field contribution of each source to any point in space by superposition. The electromagnetic contribution of each source is determined by its own intensity and spatial position, while its phase term determines the change pattern of the electromagnetic field in the time domain. These phase terms reflect the periodicity and frequency dependence of high-frequency signals. Through the distributed superposition method, the model can handle the resonance effect of multiple current sources at the same frequency and the mutual interference at different frequencies, thus forming a complete spatial electromagnetic field distribution diagram. This model is not only an independent description of each current source, but also includes the coupling characteristics between different sources. The coupling effect is a factor that cannot be ignored between high-frequency current sources, especially in high-density wire bundles, where adjacent current sources may produce strong electromagnetic coupling, resulting in the amplification of interference signals. By introducing the interaction terms between current sources in the model, the interference intensity and interference pattern between multiple current sources can be more accurately reflected. This coupling description takes into account the phase synchronization phenomenon of the current source at the same frequency and the interference effect between different frequencies, so that the electromagnetic source model can be used for complex electromagnetic interference analysis under high-frequency conditions. Specifically, this interaction term is calculated based on the distance between the source and the field point and the propagation path of the electromagnetic wave, ensuring that the model can show consistent coupling relationships at different frequencies and different locations.

[0050] In addition, the electromagnetic source model also introduces a frequency-dependent spatial attenuation factor to describe the penetration and attenuation of the electromagnetic field in the transmission medium. One of the characteristics of high-frequency electromagnetic wave propagation in the medium is the skin effect, that is, the field strength of the electromagnetic wave gradually decreases with the increase of distance, especially in the medium with high conductivity, the attenuation of the field strength is more obvious. By incorporating the skin effect into the electromagnetic source model, the attenuation characteristics of high-frequency current sources in different media can be accurately simulated. This attenuation factor depends not only on the spatial distance, but also on the frequency, so that the model can reflect the attenuation law at different frequencies, especially in the high-frequency state, it can show a strong field strength attenuation phenomenon, which is more in line with the actual physical situation. The output result of the electromagnetic source model is the electromagnetic source intensity data at each spatial point, which provides the basic input conditions for the subsequent electromagnetic field intensity calculation. The electromagnetic source intensity is the initial distribution of the electric field and magnetic field in space. In the design of new energy high-frequency wiring harnesses, these data are directly related to the calculation of transmission line characteristics, impedance matching analysis, and shielding effect evaluation. Since the model can accurately reflect the electromagnetic contribution of each current source at different positions in space, it provides a systematic method to analyze the overall electromagnetic characteristics of the wiring harness system. As the number and frequency of current sources increase, the complexity of the model will increase accordingly, but its calculation accuracy and the spatial accuracy of the electromagnetic field distribution will also increase simultaneously. This method can ensure that the calculation results of the electromagnetic source intensity are more consistent with the actual electromagnetic field distribution, especially in complex structures and multi-source conditions, the resolution of the model is further improved.

[0051] Step 2: Based on the spatial electromagnetic field intensity, calculate the equivalent transmission line parameters of the new energy high-frequency wire harness; based on the equivalent transmission line parameters, calculate the frequency-dependent characteristic impedance of the new energy high-frequency wire harness;

[0052] The distribution of electromagnetic source intensity provides the initial electromagnetic field information of each point in space, and this information determines the electromagnetic interference behavior and transmission characteristics of the high-frequency wire harness under specific frequency and geometric conditions. The operating frequency of the new energy high-frequency wire harness is high and the structure is complex. The electromagnetic field distribution around it is often not uniform, but is affected by multiple factors such as the current source position, conductivity, and dielectric. It shows spatial and frequency dependence. Therefore, the principle of this step is mainly to obtain accurate transmission line equivalent parameters by analyzing the electromagnetic field intensity in space, and these parameters will be used for further electromagnetic compatibility optimization. In this calculation process, the electric field and magnetic field intensity in space are first calculated by the spatial integration method based on the electromagnetic source intensity obtained by the distributed electromagnetic source model. The calculation of spatial integration can not only consider the independent contribution of each current source in space, but also reflect the propagation path and attenuation characteristics of electromagnetic waves in different media. Since electromagnetic waves under high-frequency conditions often have strong attenuation and refraction effects, the skin effect is also considered in the model, that is, the phenomenon that electromagnetic waves gradually weaken as the transmission distance increases. This effect is particularly significant in conductive materials, especially in high-frequency working conditions, the energy of electromagnetic waves tends to be concentrated on the surface of the material, while the interior shows a trend of rapid attenuation. This physical characteristic is introduced into the frequency-dependent attenuation factor in the process of calculating the electromagnetic field strength. Through this attenuation factor, the model can accurately reflect the changes in the field strength of the electric field and the magnetic field at different positions in the medium, thereby providing a real data basis for the extraction of transmission line parameters. After obtaining the distribution information of the electromagnetic field in space, the equivalent transmission line parameters of the new energy high-frequency wire harness are further calculated. The equivalent parameters of the transmission line include frequency-variable resistance, inductance, capacitance and conductance. These parameters describe the propagation characteristics of electromagnetic signals in high-frequency wire harnesses and are key data for electromagnetic compatibility optimization. Specifically, the frequency-variable resistance represents the loss of current in the conductor, the frequency-variable inductance describes the magnetic field effect generated by the current change, the frequency-variable capacitance reflects the electric field coupling effect between adjacent conductors, and the frequency-variable conductance is used to describe the leakage conduction behavior in the medium. Each parameter involves different electromagnetic phenomena, and the combined effect of these phenomena determines the impedance characteristics of the transmission line at different frequencies. In order to accurately calculate these equivalent parameters, this step extracts the RLCG parameters of the transmission line by analyzing the electric field and the magnetic field based on the distribution characteristics of the electromagnetic field in space. Different from the simpler impedance expression at low frequencies, under high frequency conditions, RLCG parameters all change with frequency. Therefore, in the calculation process, the present invention introduces frequency as a variable into the expression of transmission line parameters so that each parameter can change with frequency. Such frequency dependence not only enhances the adaptability of the model, but also better fits the physical characteristics of high-frequency wiring harnesses. Next, by combining the frequency-dependent resistance, inductance, capacitance and conductivity parameters, the frequency-dependent characteristic impedance of the transmission line is further calculated. Characteristic impedance is an important characteristic of a transmission line, which describes the response of the transmission line to electromagnetic signals at different frequencies.Characteristic impedance is crucial in electromagnetic compatibility design because it affects the reflection and absorption of signals in the transmission line. By substituting the frequency-dependent RLCG parameters into the calculation formula of characteristic impedance, the impedance characteristic curve of the new energy high-frequency wiring harness at different frequencies is obtained. This curve describes the propagation mode of the signal. If the characteristic impedance of the transmission line does not match the load impedance, a reflected signal will be generated, which will cause electromagnetic compatibility problems in the system. By ensuring that the characteristic impedance of the transmission line matches the load impedance as much as possible in the design, the reflected signal can be reduced and the transmission efficiency and electromagnetic compatibility of the system can be improved.

[0053] Step 3: According to the frequency-dependent characteristic impedance, the crosstalk between adjacent wire harnesses in the new energy high-frequency wire harness is analyzed and the crosstalk voltage is calculated; according to the crosstalk voltage, the radiation field of the new energy high-frequency wire harness is calculated; according to the radiation field, the shielding effectiveness of the new energy high-frequency wire harness is calculated;

[0054] First, the coupling strength between the wire bundles can be solved by the characteristic impedance. The characteristic impedance describes the impedance characteristics of the transmission line at different frequencies. In adjacent wire bundles, due to the impedance matching or mismatching of different transmission lines, different degrees of coupling will be generated between adjacent wire bundles during signal transmission. This coupling is manifested in the mutual influence of electric and magnetic fields in space, which in turn leads to electromagnetic induction between adjacent conductors. This phenomenon is called crosstalk. The crosstalk voltage is an important parameter to measure the strength of this coupling. It directly reflects the interference intensity of the signal on one wire bundle to the adjacent wire bundle. The magnitude of the crosstalk voltage depends on the current of the source wire bundle, the distance between the two, the characteristic impedance of the wire bundle, and the electromagnetic properties of the medium around the conductor. In the present invention, the coupling coefficient between each adjacent wire bundle is obtained by combining the calculation results of the characteristic impedance with the distribution of each current source, and the crosstalk voltage is calculated using the coupling coefficient. This step ensures that the degree of coupling between high-frequency signals between wire bundles can be accurately described under high-frequency working conditions, providing basic data for the next step of radiation field analysis. After obtaining the crosstalk voltage, the radiation field characteristics of the system can be further derived. High-frequency current propagates in the form of waves in the transmission line, and the existence of crosstalk causes part of the signal energy to be radiated from the wire harness to the external space in the form of electromagnetic waves. The intensity of this radiation field determines the electromagnetic interference intensity of the system and also reflects the electromagnetic compatibility level of the system. The radiation field of the high-frequency wire harness is jointly determined by its physical structure, frequency, current source intensity and other factors. By calculating the crosstalk voltage and characteristic impedance, the present invention further analyzes the radiation field of the wire harness and obtains the radiation electric field intensity of the system at a specific position in space. The radiation field calculation takes into account the phase relationship between the source point and the field point, the attenuation characteristics of the propagation path, and the directional characteristics of the electromagnetic wave in space, so that the radiation distribution of the system under high-frequency conditions can be accurately predicted. This process ensures the accuracy of the radiation field intensity data and lays a data foundation for the subsequent calculation of shielding effectiveness. The calculation of shielding effectiveness is an important part of optimizing the electromagnetic compatibility of the high-frequency wire harness system. Through the evaluation of shielding effectiveness, it can be judged whether the existing shielding design is sufficient to suppress the interference of the radiation field to the external environment. Shielding effectiveness is defined as the logarithmic ratio of the radiation field intensity of the system in the unshielded and shielded states, reflecting the attenuation effect of the shielding layer on electromagnetic waves. For high-frequency wiring harnesses, the shielding effectiveness depends not only on the electrical conductivity and magnetic permeability of the shielding material, but also on the thickness, frequency and spatial position of the shielding layer. In the present invention, the calculation of the shielding effectiveness is based on the aforementioned radiation field data, and the numerical value of the shielding effectiveness is obtained by comparing the radiation intensity with and without shielding conditions. A frequency-dependent attenuation factor is introduced in the calculation process, which can accurately describe the propagation characteristics of electromagnetic waves in the shielding layer and reflect the absorption capacity of the shielding material at different frequencies. By adjusting the thickness and material properties of the shielding layer, the optimal shielding design can be found, thereby achieving effective suppression of high-frequency radiation.

[0055] Step 4: According to step 1, step 2 and step 3, set constraints, and establish an objective function under the constraints, and iteratively solve the objective function to find the optimal design parameter vector of the corresponding new energy high-frequency wiring harness; design the new energy high-frequency wiring harness through the optimal design parameter vector; the elements of the optimal design parameter vector include: the number of current sources, frequency-variable resistance, frequency-variable inductance, frequency-variable capacitance, frequency-variable conductance, shielding layer thickness and wiring harness current of the new energy high-frequency wiring harness.

[0056] First, the optimization process starts with the establishment of the objective function. The definition of the objective function is based on the overall performance of the high-frequency wiring harness system in terms of electromagnetic compatibility, with the goal of minimizing the radiation field intensity, crosstalk voltage, and ensuring that the shielding effectiveness meets specific standards. Since the interference effect of the high-frequency wiring harness system is different in different frequency ranges, the objective function weights the impact of different frequencies, so that the electromagnetic compatibility indicators can be optimized preferentially in the main working frequency band of the system. After setting the objective function, several constraints are proposed in combination with the physical characteristics of the new energy high-frequency wiring harness. These constraints include the limit of radiation intensity, the maximum allowable value of crosstalk voltage, and the minimum standard of shielding effectiveness. In addition, in order to ensure the stability of the wiring harness system in practical applications, the range limit of characteristic impedance is also used as a constraint, so as to ensure that the system will not cause reflection and power loss due to impedance mismatch in the high-frequency state. By combining these objectives and constraints, the optimization problem is transformed into a multi-objective constrained optimization problem. Next, the optimization solution process is carried out using an iterative algorithm to gradually adjust the design parameter vector to approach the optimal solution. The design parameter vector includes multiple factors such as the number of current sources, frequency-dependent resistance, inductance, capacitance, conductivity, shielding layer thickness, and harness current. These parameters determine the electromagnetic characteristics of the system. Therefore, in the iterative process, the values ​​of different parameters directly affect the effect of electromagnetic compatibility optimization. In each iteration, the algorithm calculates the corresponding electromagnetic compatibility index value based on the current design parameter vector, evaluates whether it meets the constraints, and brings the result into the objective function. If the objective function value is large, it means that the current design does not meet the optimal electromagnetic compatibility standard. The algorithm will adjust the parameter vector to further reduce the objective function value; if the objective function value is close to the minimum value and all constraints are met, it means that the current design parameter combination has achieved a better electromagnetic compatibility level. Through this iterative adjustment, the optimal parameter combination is continuously searched, thereby realizing the optimal design of the high-frequency harness system.

[0057] The difficulty of this optimization process lies in the comprehensive balance of multiple objectives and multiple constraints, because different design parameters will have multiple effects on the electromagnetic compatibility indicators. For example, increasing the thickness of the shielding layer can effectively improve the shielding effectiveness, thereby reducing the radiation field intensity, but it may also increase the frequency-dependent resistance of the system, thereby affecting the transmission efficiency of the system. Similarly, adjusting the number of current sources or the current intensity of the harness may reduce the crosstalk effect, but it will also change the characteristic impedance of the system and cause its matching to shift. Therefore, the optimization algorithm needs to dynamically balance the influence of each design parameter during the iteration process to find the minimum value of the objective function while satisfying all constraints. Finally, the optimal design parameter vector obtained through multiple rounds of iterative calculations represents the best electromagnetic compatibility solution for new energy high-frequency harnesses under current design requirements. This optimal parameter vector provides a more accurate design reference for the harness system, which can not only ensure that its radiation interference to the outside world is minimized within the working frequency band, but also effectively suppress the crosstalk inside the harness system and ensure the stability of signal transmission. With this optimization design result, engineers can design an actual harness system based on these parameters to meet the electromagnetic compatibility requirements of new energy equipment under high-frequency working conditions.

[0058] Embodiment 2: In step 1, the electromagnetic source model of the new energy high-frequency wire beam is established by the following formula to obtain the electromagnetic source intensity of the new energy high-frequency wire beam at each spatial point:

[0059]

[0060] Where S(r,ω) represents the electromagnetic source intensity at a spatial point r at a given frequency ω; N is the number of current sources in the new energy high-frequency wire harness; i is an integer subscript index; I i is the current intensity of the i-th current source; is the attenuation factor of the current source intensity during spatial propagation, which simulates the inverse square attenuation characteristic of the distance from the current source to the spatial point; r i is the position vector of the i-th current source; t is the time variable; j is the negative sign; Represents the magnetization intensity M i (r) is the curl operation term; M i (r) is the magnetization at the i-th current source, is the curl operator and represents the effect of the magnetic field generated by the current source on the magnetization of the surrounding area.

[0061] Specifically, in this model, S(r,ω) represents the electromagnetic source intensity at a certain point r in space at a frequency ω. The source intensity is mainly determined by factors such as the intensity, position, and magnetization intensity of the current source. In the design of new energy high-frequency wiring harnesses, this electromagnetic source model is particularly critical because it can truly reflect the distribution of electromagnetic interference sources in the wiring harness system under high-frequency conditions. By calculating the electromagnetic field intensity contribution of each current source, the formula integrates the superposition effect of multi-source interference, so that the electromagnetic source intensity at any point in space can be accurately calculated. The first term in the model, namely describes the electromagnetic contribution of the i-th current source to the spatial point r. The strength of the current source is determined by the current I i It indicates its contribution to the electromagnetic field under high-frequency signals, and is a distance attenuation factor, which describes the attenuation characteristics of the electric field strength from the current source to the spatial point r as the inverse of the square of the distance. This attenuation characteristic conforms to the law of electromagnetic radiation propagation in free space, ensuring the physical rationality of the model. The greater the distance, the smaller the influence of the current source on the point, which is also consistent with the physical law of the actual electromagnetic field distribution. In this term, exp(-jωt) is also included as a phase factor, which describes the time dependence and frequency characteristics of the electromagnetic wave. The current source in the high-frequency beam is usually in an AC state, so the phase term reflects the dynamic changes of the current source, thereby more realistically simulating the time-varying characteristics of the electromagnetic source. In addition, the unit vector Represents the direction from the current source position to the spatial point r. The unit vector ensures that the model can accurately reflect the directionality of electromagnetic field propagation in space, so that the distribution of electromagnetic field in different directions can be more comprehensively described.

[0062] The second term in the formula The curl term represents the magnetization intensity. This part is used to describe the influence of the magnetic field generated by the current source in space on the magnetization of the surrounding area. A high-frequency current source will not only form an electric field around it, but also cause a magnetization effect in space through the change of the magnetic field. Especially in the presence of a magnetically permeable medium, this magnetization effect will lead to a more complex electromagnetic interference distribution. Curl operator It is used to calculate the spatial distribution of magnetization and its contribution to the electromagnetic field. This operation can capture the variation of magnetization in all directions. i(r) represents the magnetic field effect of the current source on the surrounding space, which reflects how the magnetic field generated by the high-frequency current source in its area affects the magnetism of the surrounding medium. This item is particularly important because under high-frequency conditions, the propagation of the electromagnetic field is not only affected by the electric field strength, but also causes magnetization effects in space due to changes in the magnetic field. By adding this item to the model, the spatial influence of the electromagnetic source can be described in a larger range, thereby improving the accuracy of the calculation results. The output result of the electromagnetic source model is the electromagnetic source intensity S(r,ω) of the new energy high-frequency wire bundle at each spatial point. These data provide initial conditions for subsequent electromagnetic field intensity calculations. Due to the complexity of electromagnetic interference under high-frequency conditions, this distributed electromagnetic source model can capture the field intensity changes of each current source in different spatial positions and directions, making the entire electromagnetic compatibility analysis process more accurate. The multiple components in the model enable the electromagnetic source intensity of each spatial point to be calculated independently, which is particularly important under multi-source conditions, because the electromagnetic field generated by each current source in space will overlap and interfere with other sources. Therefore, to obtain the overall electromagnetic field distribution, it is necessary to calculate the comprehensive influence of all current sources.

[0063] Embodiment 3: In step 1, the electromagnetic field strength in space is calculated based on the electromagnetic source strength by the following formula:

[0064]

[0065] Where E(r,ω) represents the electromagnetic field intensity at a given frequency ω at a spatial point r; the skin depth δ(ω) defines the penetration depth of the electric field in the medium at the frequency ω; r' is the position integral variable;

[0066] G(r,r') is the corresponding propagation Green's function under the position integral variable; S(r',ω) is the corresponding form of S(r,ω) under the position integral variable; V is the spatial range of the new energy high-frequency harness.

[0067] Specifically, in this formula, the electromagnetic field intensity E(r,ω) represents the electric field intensity at the spatial point r at the frequency ω, which is the cumulative result of the source intensity calculated by the electromagnetic source model in space. This accumulation process is completed through triple integral ∫∫∫. The integration process gradually accumulates the influence of the current source on each point in space to reflect the electric field distribution of the harness system in the overall spatial range. The integral variable r' represents the position of each source point in space. During the integration process, r' is taken point by point to calculate the electric field contribution of all current sources to the spatial point r. This integration method ensures that the electric field intensity at any point in space can be obtained through accurate calculation, thereby achieving full spatial coverage of high-frequency electromagnetic fields. The Green's function G(r,r') is an indispensable key part of this formula. It describes the propagation characteristics of electromagnetic waves in space, especially the mutual influence of electric fields between different positions. In electromagnetic field theory, the Green's function can be understood as a propagation weight function, which reflects the propagation behavior of electromagnetic waves in the medium, such as reflection, refraction and attenuation, by weighting the propagation path between the current source and the spatial point. By introducing Green's function, the model can not only describe the propagation of electromagnetic waves in free space, but also effectively adapt to the propagation in different media. The introduction of Green's function ensures that the calculation of electromagnetic field strength can adapt to various spatial propagation environments, and the changes in electric field strength in different media and different propagation distances can be accurately calculated. This feature is especially important in complex environments, because new energy high-frequency wiring harness systems often transmit signals in multiple media, and different media have different electromagnetic propagation characteristics, which directly affects the distribution of the electromagnetic field.

[0068] The exponential decay factor introduced in the formula It is a key term used to describe the skin effect. The skin effect is a basic characteristic of high-frequency electromagnetic waves propagating in conductive media. It describes the concentrated distribution characteristics of electromagnetic waves on the surface of the medium, that is, the electromagnetic field is mainly concentrated on the surface of the conductor under high-frequency conditions, and decays rapidly inside the conductor as the distance increases. The skin depth δ(ω) describes the penetration depth of electromagnetic waves at different frequencies. The smaller the δ(ω) value, the faster the electromagnetic wave decays in the conductor. This term can be used to characterize the energy distribution of electromagnetic waves at different frequencies and in different media. For example, in a highly conductive medium, the energy of high-frequency electromagnetic waves will quickly concentrate on the surface, with a small penetration depth and faster decay; while in a low-conductive medium, the electromagnetic wave penetrates deeper. Therefore, the introduction of the exponential decay factor can not only reflect the skin effect of electromagnetic waves, but also accurately describe the field strength attenuation at different frequencies and in different media, so that the electric field calculation results are closer to the actual physical environment. In the triple integral calculation process, the electromagnetic source intensity S(r',ω) is the initial excitation source in the formula, which describes the electric field contribution of each current source in the high-frequency harness system in space. The electromagnetic source intensity is obtained from the previous electromagnetic source model and is accumulated point by point in the triple integral to transfer the comprehensive electric field effect of the current source to each position point in space. This process can be understood as the accumulation of the field strength distribution generated by each current source at different spatial positions. The electric field contributions of all current sources at a specific position are combined to obtain the actual electric field strength at that position. Since the current sources in high-frequency wire bundles usually have different distributions in space, the calculation of the electric field strength must consider the different positions and directions of each source point. Through this spatial integration method, a full-scale simulation of the electric field distribution can be achieved, ensuring that the electric field strength at any position point in space can be obtained through accurate calculation. The principle of the electromagnetic field strength calculation formula also involves the phase relationship and spatial attenuation characteristics of electromagnetic waves. Under high-frequency conditions, the phase change of electromagnetic waves has an important influence on the electric field distribution. The distance from the source point to the field point and the characteristics of the propagation medium will cause the phase change of the electromagnetic wave, thereby affecting the final intensity distribution of the electric field. One of the functions of the Green function is to take this phase effect into account. It describes the phase change of electromagnetic waves at different positions through the distance dependence of the propagation path, making the electric field distribution more consistent with the phase superposition law in actual high-frequency propagation. In addition, the introduction of the skin effect term not only reflects the attenuation characteristics, but also makes the change of the electric field strength at different positions show a real attenuation law. The setting of the skin depth can ensure that the calculated electric field strength will not exceed the limitations of the actual physical environment, making the results more realistic.

[0069] Embodiment 4: In step 2, the equivalent transmission line parameters of the new energy high-frequency wire harness are calculated based on the spatial electromagnetic field intensity by the following formula:

[0070]

[0071] in, is the equivalent transmission line parameter of the new energy high-frequency wiring harness; R(ω) is the frequency-dependent resistance at a given frequency ω; |E(r,ω)| is the modulus of the electric field intensity; σ c is the conductivity of the conductor of the new energy high-frequency wiring harness; C represents the closed path around the new energy high-frequency wiring harness; dl represents the distance integral variable on the closed path around the new energy high-frequency wiring harness; L(ω) is the frequency-variable inductance at a given frequency ω; μ0 is the vacuum permeability; d max is the diameter of the outer conductor of the new energy high-frequency wiring harness; d min is the diameter of the inner conductor of the new energy high-frequency wiring harness; μ r is the relative magnetic permeability of the new energy high-frequency wire harness, which indicates the magnetic permeability of the material of the new energy high-frequency wire harness relative to vacuum; ε r is the relative dielectric constant of the new energy high-frequency wire harness, which indicates the capacitance characteristics of the material of the new energy high-frequency wire harness relative to vacuum; ε0 is the dielectric constant of vacuum; C(ω) is the frequency-variable capacitance at a given frequency ω; G(ω) is the frequency-variable conductance at a given frequency ω; σ d is the conductivity of the medium.

[0072] Specifically, the frequency-dependent resistance R(ω) represents the energy loss characteristics of the high-frequency harness conductor at a specific frequency. The calculation process of resistance is based on the modulus |E(r,ω)| of the electromagnetic field strength in space, and is obtained by integrating the closed path C. By accumulating the ratio of the square of the electric field strength on the path around the conductor, the total value of the power loss on the entire path can be obtained. This process actually simulates the gradual loss of energy of the conductor under the excitation of high-frequency current. The essence of resistance is energy consumption, which causes the current to gradually attenuate during transmission. Under high-frequency conditions, electromagnetic waves will produce a "skin effect", that is, the current is concentrated in the surface area of ​​the conductor, rather than being evenly distributed inside the conductor. The skin effect increases the energy consumption of high-frequency current on the surface of the conductor, so the high-frequency resistance is usually higher than the low-frequency resistance. The conductivity σ in the formula c It is the key to resistance calculation and reflects the conductor's ability to react to current. The lower the conductor conductivity, the greater the resistance, the more energy is consumed, and the more severe the signal attenuation during transmission. The calculation of frequency-variable resistance provides a basis for power loss control in electromagnetic compatibility design, so that the resistance characteristics can be optimized by controlling the conductivity of the material during design. Secondly, the frequency-variable inductance L (ω) describes the magnetic field characteristics generated by the high-frequency harness under the action of alternating current. The inductance parameters are determined by the geometric structure of the conductor and the magnetic permeability of the material. The vacuum permeability μ0 is a basic constant in inductance calculation, which is used to determine the distribution of the magnetic field around the conductor in the absence of external magnetic materials. Relative permeability μ rIt is the magnetic conductivity of the conductor material. Relative to vacuum, its value determines the multiple by which the magnetic field is amplified in the material. max and inner diameter d min The logarithmic ratio between reflects the effect of geometry on the magnetic field. The magnetic field will change periodically under high-frequency current and form a stable magnetic induction effect around the conductor. This effect is essentially an inductance effect. The generated magnetic field will react to the current, thereby limiting the rate of change of the current. The calculation of frequency-variable inductance can accurately quantify the magnetic field effect of high-frequency signals, allowing designers to adjust the inductance value of the harness according to the magnetic permeability and geometry. In electromagnetic compatibility design, the size of the inductor affects the total impedance and signal delay of the transmission line. The appropriate inductance value can effectively balance the magnetic field strength and current stability.

[0073] The third parameter is the frequency-dependent capacitance C(ω), which is used to describe the electric field coupling characteristics between conductors. The calculation of capacitance involves the vacuum dielectric constant ε0 and the relative dielectric constant ε r , which together determine the coupling strength of the electric field in space. The vacuum dielectric constant is a basic constant that indicates the capacitive characteristics of the electric field propagating in a vacuum, while the relative dielectric constant reflects the amplification or weakening effect of the medium around the conductor on the electric field. Under high-frequency conditions, electromagnetic waves will form a strong electric field around the conductor, and the coupling characteristics formed by the mutual attraction or repulsion of charges between conductors are manifested as a capacitive effect. The logarithmic ratio of the outer diameter to the inner diameter of the conductor reflects the coupling at different spatial distances. As the distance between the conductors increases, the capacitance decreases accordingly. This relationship conforms to the physical law that high-frequency electromagnetic waves gradually attenuate in space. The larger the capacitance, the stronger the coupling between the conductors, which is manifested as a more concentrated electric field between the conductors. This electric field concentration effect will affect the propagation speed of high-frequency signals, thereby affecting the transmission performance in electromagnetic compatibility design. The calculation of frequency-variable capacitance provides a basis for optimizing the electric field distribution of the transmission line, allowing designers to control the dielectric constant and geometric parameters to adjust the capacitance characteristics. Finally, the frequency-variable conductance G(ω) describes the leakage conductance characteristics of the medium around the conductor. Conductivity σ dIt is an important parameter in the calculation of frequency-variable conductance, which reflects the leakage conductance of the medium under high-frequency signals. The calculation of conductivity parameters involves the geometric properties of the conductor, and the logarithmic ratio of the outer diameter to the inner diameter of the conductor reflects the influence of geometric parameters on leakage conductance. Frequency-variable conductance is of great significance in electromagnetic compatibility design because it describes the process of electromagnetic signal penetration and leakage in the medium. In the propagation of high-frequency signals, the electric field will form leakage conductance around the conductor, causing the signal to gradually attenuate during the propagation process. The size of the frequency-variable conductance directly determines the energy loss of the signal. By calculating the ratio of the outer diameter to the inner diameter of the conductor, the influencing factors of the frequency-variable conductance can be obtained, thereby guiding the material selection and geometric design during the design. Higher leakage conductance will cause high-frequency signals to decay rapidly, which has an adverse effect on the transmission performance of high-frequency electromagnetic signals. The calculation of frequency-variable conductance enables the leakage conductance in the medium to be accurately controlled in electromagnetic compatibility design to reduce the loss of high-frequency signals in transmission.

[0074] Embodiment 5: In step 2, the frequency-dependent characteristic impedance of the new energy high-frequency wiring harness is calculated based on the equivalent transmission line parameters by the following formula:

[0075]

[0076] Among them, Z c (ω) is the frequency-dependent characteristic impedance at a given frequency ω; γ(ω) is the propagation constant at a given frequency ω; X is the length of the new energy high-frequency wiring harness.

[0077] Specifically, the calculation formula of characteristic impedance includes the equivalent transmission line parameters of the transmission line, including frequency-variable resistance R(ω), frequency-variable inductance L(ω), frequency-variable capacitance C(ω) and frequency-variable conductance G(ω). These parameters describe the attenuation, coupling, energy storage and leakage characteristics of electromagnetic signals in conductors and media respectively. By substituting these parameters into the characteristic impedance formula, the frequency-variable impedance characteristics of the transmission line can be obtained. The calculation formula of characteristic impedance reflects the complex behavior of electromagnetic signals in high-frequency wire harnesses, especially under high-frequency conditions, due to the enhancement of various effects on electromagnetic waves in media and conductors, the impedance characteristics show a strong frequency dependence. By calculating the characteristic impedance Z c(ω) can effectively describe the performance of the transmission line during high-frequency signal propagation, including signal attenuation, energy loss and reflection. The numerator R(ω)+jωL(ω) in the formula represents the combined effect of resistance and inductance during electromagnetic signal transmission. The frequency-dependent resistance R(ω) represents the energy loss of the conductor to the signal. At high frequencies, due to the skin effect, the current is concentrated on the surface of the conductor, resulting in increased surface loss. The frequency-dependent inductance L(ω) describes the magnetic field effect of the transmission line under the action of high-frequency signals. The inductance effect will cause the signal to interact with the magnetic field during transmission, thereby exerting a reaction force on the change of current. The complex form of this part enables the impedance formula to better simulate the characteristics of high-frequency signals in conductors under the dual action of electric and magnetic fields. The complex term jωL(ω) contains the angular frequency ω, which indicates that the influence of inductance increases with the increase of frequency. Therefore, at high frequencies, the reaction of inductance to the signal is more significant. Overall, this part reflects the influence of conductor characteristics in transmission lines on signal propagation.

[0078] The denominator G(ω)+jωC(ω) represents the effect of the medium on the signal, where the frequency-dependent conductance G(ω) describes the leakage conduction characteristics of the medium, which is manifested as the energy loss caused by the leakage conduction of the medium during the transmission of the signal. The frequency-dependent capacitance C(ω) describes the coupling effect of the electric field between conductors, that is, the effect of the distribution of the electric field in the transmission line on signal propagation. Under high-frequency conditions, the distribution of the electric field in space depends not only on the geometry of the transmission line, but also on the dielectric properties of the surrounding medium. The complex term jωC(ω) indicates the frequency dependence of the capacitance effect. As the frequency increases, the coupling effect of the capacitance on signal propagation also increases. The introduction of the capacitance term enables the model to truly reflect the electric field coupling and energy storage effects between conductors. The propagation constant γ(ω) is another key part of the characteristic impedance formula, which describes the attenuation and phase change of the signal when it propagates in the transmission line. The propagation constant is calculated by combining the equivalent transmission line parameters and is defined as This propagation constant is used in the formula to represent the attenuation factor of the signal, which is actually the overall impedance of the high-frequency signal in the transmission line. The real part of the propagation constant represents the attenuation degree of the signal during the spatial propagation process, while the imaginary part represents the phase change of the signal. The attenuation degree determines the speed of energy loss during the signal propagation process, while the phase change reflects the change in the speed and relative position of the electromagnetic wave during the transmission process. The size of the propagation constant directly affects the attenuation characteristics of the signal in the transmission line. The larger the propagation constant, the faster the signal attenuates and the more obvious the phase change. The exponential term exp(-γ(ω)X) in the formula describes the attenuation of the signal over the transmission line length X. Since the propagation constant contains frequency dependence, the attenuation rate of the signal in the transmission line will change with the change of frequency. This exponential term reflects the overall energy loss of the signal over the transmission line length, that is, after the signal passes through the transmission line with a length of X, its electric field strength will gradually weaken according to the exponential law. The introduction of this term not only takes into account the influence of the transmission line length, but also combines the effect of the propagation constant on signal attenuation, so that the calculation result is closer to the actual situation in the high-frequency environment. This part is of great significance for long-distance signal transmission, especially in the high-frequency state, the attenuation effect of the signal during transmission will become more obvious. The calculation results of the characteristic impedance can not only be used to judge the electromagnetic compatibility of the transmission line, but also to analyze the reflection of the signal. When the characteristic impedance of the transmission line does not match the load impedance, the signal will be reflected on the transmission line, causing part of the energy to return to the source, thereby reducing the transmission efficiency of the system and may cause interference. Therefore, by optimizing the characteristic impedance, matching with the load impedance can be achieved, thereby minimizing reflections and improving the transmission efficiency of the system. The frequency dependence of the characteristic impedance also makes it exhibit different transmission characteristics at different frequencies. Especially under high-frequency conditions, the reflection and interference of the signal are more complicated. Therefore, the calculation of the characteristic impedance is crucial for the optimal design of high-frequency wiring harnesses.

[0079] Embodiment 6: In step 3, the crosstalk between adjacent wire harnesses in the new energy high-frequency wire harness is analyzed according to the frequency-dependent characteristic impedance by the following formula to calculate the crosstalk voltage:

[0080]

[0081] Where Z0 is the nominal characteristic impedance; M 12 (ω) is the mutual inductance coefficient, which indicates the degree of electromagnetic coupling between two wire bundles. It is the mutual inductance of adjacent wire bundles at frequency ω; V xt (r,ω) is the crosstalk voltage at the spatial point r at a given frequency ω.

[0082] Specifically, in the formula, the crosstalk voltage V xt(r,ω) is the voltage at the spatial point r at the frequency ω. The crosstalk voltage is mainly generated by the characteristic impedance Z of the wiring harness. c (ω), the mutual inductance M of adjacent wire bundles 12 (ω) and the rate of change of the current on the harness The characteristic impedance Z c (ω) represents the propagation impedance characteristics of the signal in the transmission harness, which has a direct impact on the magnitude of the crosstalk voltage. When the characteristic impedance is high, the signal is prone to reflection during transmission, thereby generating greater electromagnetic interference on the adjacent harness. Therefore, the ratio of the crosstalk voltage to the characteristic impedance is It plays a regulating role in the formula, where Z0 is the nominal characteristic impedance of the system, representing the impedance value under ideal conditions. Through this ratio, the influence of the actual characteristic impedance on the crosstalk voltage can be analyzed when it deviates from the ideal impedance. 12 (ω) is a crucial parameter in crosstalk calculation, which represents the coupling strength between two adjacent wire bundles. Under high-frequency conditions, the electromagnetic coupling between wire bundles increases with increasing frequency, so the mutual inductance coefficient also shows obvious frequency dependence. Mutual inductance reflects how the current change in one wire bundle generates an induced voltage in another adjacent wire bundle. The higher the mutual inductance coefficient, the stronger the coupling between the wire bundles, and the more likely the current change in the adjacent wire bundle will affect the signal of the other wire bundle, resulting in a larger crosstalk voltage. The size of the mutual inductance coefficient depends on the distance, geometric arrangement, material properties and frequency characteristics between the wire bundles. The closer the distance between adjacent wire bundles, the greater the mutual inductance value, and the more significant the impact of the crosstalk voltage. Therefore, the calculation of the mutual inductance coefficient is crucial to accurately predict the crosstalk voltage. By adjusting the arrangement and distance of the wire bundles, the size of the crosstalk can be effectively controlled.

[0083] The current change rate in the formula It reflects the time variation of high-frequency signals in adjacent wire bundles. Under high-frequency conditions, the current changes rapidly with time. The higher the rate of change, the more drastic the change in the electromagnetic field, which in turn produces stronger interference to adjacent wire bundles. The current change rate term describes the impact of the transient characteristics of high-frequency signals on crosstalk. The rapid change of transient current will cause drastic fluctuations in the electromagnetic field in the surrounding space, thereby inducing voltage fluctuations in adjacent wire bundles through mutual inductance coupling. Therefore, the introduction of this term further reflects the contribution of high-frequency transient current to the crosstalk voltage. The propagation constant γ(ω) is a parameter that describes the propagation characteristics of the signal in the transmission line, which includes the attenuation and phase change of the signal. The attenuation factor in the propagation constant describes the process in which the signal gradually weakens as the propagation distance increases, especially when the propagation distance is long, the energy of the signal will gradually decay. This attenuation effect is reflected in the exponential term exp(-γ(ω)|r-z'|) in the formula, which describes the degree of attenuation of the signal when it propagates between two locations. The signal is gradually weakened by the influence of resistance and inductance during the propagation process. The longer the propagation distance, the more obvious the attenuation. Therefore, the interference intensity between adjacent wires will also decrease with the increase of distance. The introduction of the exponential attenuation term ensures that the calculation result of the crosstalk voltage conforms to the actual physical attenuation law under long distance conditions. Integral term It means that all positions on the transmission line length X are accumulated. This process is used to calculate the cumulative effect of interference of adjacent harnesses on the entire transmission line length. Since the change of current will produce different electromagnetic field distributions at various positions of the transmission line, the contribution of each section on the entire transmission line length to the crosstalk voltage can be accumulated through integration. In other words, the integration process makes the calculation of the crosstalk voltage cover the comprehensive influence of all positions on the transmission line, thereby obtaining an overall interference value. This integration method can not only capture the electromagnetic interference at a local position, but also comprehensively consider the influence of the transmission line length on the crosstalk voltage. Especially in the case of a longer transmission line, the integral term can reflect the cumulative effect of interference. Through the combination of the above items, the calculation formula of the crosstalk voltage fully describes the electromagnetic interference distribution of the high-frequency harness in actual operation. The interaction of parameters such as frequency-dependent characteristic impedance, mutual inductance, current change rate, propagation constant and transmission line length enables the crosstalk voltage to accurately reflect the interference intensity at different frequencies and different positions. The electromagnetic compatibility design of high-frequency harnesses needs to find a balance between these parameters to achieve effective control of crosstalk. This calculation formula provides a theoretical basis that enables designers to reduce crosstalk effects by adjusting characteristic impedance, increasing the spacing between wires, or changing the arrangement of wires, thereby optimizing the electromagnetic compatibility of high-frequency wire harnesses.

[0084] Embodiment 7: In step 3, the radiation field of the new energy high-frequency wiring harness is calculated according to the crosstalk voltage using the following formula:

[0085]

[0086] Among them, E rad (r,ω) represents the radiation field at the spatial point r at a given frequency ω after the shielding layer is installed; k is the wave number; k is the wave vector.

[0087] Specifically, the radiation field E rad (r,ω) represents the electric field strength at a given frequency ω at a spatial point r. This electric field strength is generated by the crosstalk voltage V generated by the transmission line. xt (r,ω) directly induces the crosstalk voltage, which represents the electromagnetic coupling effect between adjacent wires, and this coupled signal will form a radiation field in space. Since the electromagnetic radiation of high-frequency wires fluctuates in frequency, its radiation characteristics need to be comprehensively analyzed by frequency, spatial distance and transmission line characteristics. In this formula, the combination of various parameters enables the calculation of the radiation field to accurately reflect the electromagnetic intensity at different spatial points. Represents the initial excitation coefficient of the radiation field, where j represents the imaginary unit, ω is the angular frequency, and μ0 is the vacuum permeability. This coefficient plays an important role in the calculation of the radiation field. The introduction of the angular frequency ω shows that the electric field strength increases with the increase of frequency. The higher the frequency, the greater the intensity of the radiation field. The magnetic permeability μ0 describes the propagation ability of electromagnetic waves in a vacuum, which affects the propagation behavior of the electromagnetic field in space. The imaginary form of this term indicates that the radiation field contains phase information, and the imaginary unit j indicates that the phase of the radiation field fluctuates with time, which is determined by the fluctuation characteristics of the high-frequency signal. Through this coefficient, the initial intensity and phase information of the radiation field can be accurately described. The components in the formula It is the ratio of the crosstalk voltage to the frequency-dependent characteristic impedance, which indicates the effect of the crosstalk voltage on the radiation field strength. c (ω) is the impedance value of the transmission line at frequency ω. A larger characteristic impedance means that the transmission line imposes greater restrictions on the change of current, thereby reducing the radiation of the external electric field. The larger the crosstalk voltage, the greater the intensity of the electric field radiation. By calculating the ratio of the crosstalk voltage to the characteristic impedance, the radiation characteristics of the harness at different frequencies can be evaluated, especially in the frequency band where the characteristic impedance changes significantly, the radiation field intensity will fluctuate greatly.

[0088] The radiation field formula also contains a term related to the propagation distance, namely Where k is the wave number, and |r-r'| represents the distance between the spatial points r and r'. The wave number k is the ratio of frequency to the speed of light, and it describes the propagation characteristics of electromagnetic waves. As the propagation distance |r-r'| increases, the electric field strength will gradually decay, and this characteristic is realized by the denominator |r-r'|. The denominator reflects the attenuation relationship of the radiation field, that is, the electric field intensity decreases with the increase of the propagation distance, which conforms to the inverse attenuation characteristics of electromagnetic waves in free space. The exponential term exp(-jk|r-r'|) reflects the phase change and frequency dependence of the electromagnetic wave. Since electromagnetic waves experience periodic fluctuations when propagating in space, the change in phase directly determines the direction and amplitude of the electric field. The imaginary exponential form of this term reflects the phase attenuation of the radiation field with the propagation distance. Finally, the integral term Represents the accumulation along the length of the transmission line. This integral superimposes the radiation intensity at different positions in space, thereby obtaining the contribution of the entire harness system to the radiation field in space. During the transmission of high-frequency signals, the crosstalk voltage at different positions contributes differently to the radiation field, so the contributions of these different positions can be accumulated through integration to form an overall radiation intensity distribution. This integration process ensures the accuracy of the radiation field intensity in space, especially under the condition of longer transmission lines. Integration can more comprehensively describe the propagation and distribution of electromagnetic fields in space.

[0089] Embodiment 8: In step 3, the shielding effectiveness of the new energy high-frequency wiring harness is calculated according to the radiation field using the following formula:

[0090]

[0091] Among them, D is the thickness of the shielding layer of the new energy high-frequency wire harness; SE(ω) is the shielding effectiveness at frequency ω, in decibels; E0(r,ω) is the radiation field at the spatial point r at frequency ω when there is no shielding; α(ω) represents the attenuation constant at frequency ω, which determines the absorption intensity of the shielding layer to electromagnetic waves and is the set value.

[0092] Specifically, the first term in the formula Describes the attenuation of the radiation field in the shielding layer. rad (r, ω) is the radiation field intensity at the spatial point r after the shielding layer is installed, while E0(r, ω) represents the radiation field intensity when there is no shielding. By calculating the ratio of the two, the attenuation effect of the shielding layer on electromagnetic waves at this spatial point can be obtained. The logarithmic form of this term means that the shielding effectiveness is measured in decibels (dB), which is convenient for intuitively evaluating the effectiveness of the shielding layer. The higher the decibel value of the shielding effectiveness, the better the attenuation effect of the shielding layer, the smaller the intensity of the radiation field behind the shielding layer, and the lower the electromagnetic interference. The calculation of this part directly reflects the shielding ability of the shielding layer against electromagnetic waves, and provides guidance for designing shielding materials and optimizing the thickness of the shielding layer. The second term of the formula It shows the influence of the material properties in the shielding layer on the absorption intensity of electromagnetic waves. The attenuation constant α(ω) in this item is a set value, which reflects the absorption capacity of the shielding material at the frequency ω. At different frequencies, the penetration depth and absorption characteristics of electromagnetic waves will be different, so the attenuation capacity of the shielding material is also frequency-dependent. The larger the attenuation constant α(ω), the stronger the shielding material's absorption capacity for electromagnetic waves, which can more effectively reduce the radiation field intensity. In this item, Expresses the material's magnetic permeability μ r and conductivity σ c Impact on shielding effectiveness. Magnetic permeability μ r It indicates the magnetic conductivity of the material relative to vacuum. The higher the magnetic permeability, the stronger the shielding material's absorption of the magnetic field, thereby improving the shielding effectiveness. c Describes the electrical conductivity of the material. The higher the electrical conductivity of the material, the stronger its ability to reflect electromagnetic waves, which can effectively reduce the penetration and propagation of electromagnetic waves, thus providing a better shielding effect. By combining magnetic permeability and electrical conductivity, the absorption and reflection characteristics of the shielding material to electromagnetic waves can be comprehensively reflected, thereby accurately estimating its shielding effectiveness. Represents the characteristic impedance Z within the shielding layer thickness D c (ω) The impact on shielding effectiveness. As the thickness of the shielding layer D increases, the path of the electromagnetic wave in the shielding layer becomes longer. Such a path extension will lead to greater attenuation, thereby enhancing the shielding effect. This integration process actually describes the cumulative effect of the thickness of the shielding layer on the absorption of electromagnetic waves. Characteristic impedance | Z c (ω)|, as a frequency-dependent impedance value, reflects the resistance to electromagnetic waves at different frequencies. A higher characteristic impedance means that electromagnetic waves are more difficult to propagate in the shielding layer, and such a shielding material has a stronger ability to reflect and absorb electromagnetic waves. Therefore, by integrating the thickness of the shielding layer, the electromagnetic compatibility performance of the shielding layer at different thicknesses can be accurately described.

[0093] Example 9: In step 4, set the constraint conditions by the following formula:

[0094] |E rad (r,ω)| <E lim ;

[0095] |V xt (z,ω)| <V lim ;

[0096] SE(ω)>SE min ;

[0097] |Z c (ω)-Z0|<ΔZ max ;

[0098] Among them, E lim is the set radiation limit; V lim is the set crosstalk limit; SE ref is the target shielding effectiveness; ΔZ max is the characteristic impedance threshold set; the objective function is defined as:

[0099]

[0100] min{EMC total};

[0101] Among them, EMC total is the performance index; ω1 is the set frequency lower limit; ω2 is the set frequency upper limit.

[0102] Specifically, among the constraints of this formula, the first is the limitation of radiation field intensity.

[0103] E rad (r,ω)| <E lim , where E lim is the radiation limit. This limit is used to control the radiation field strength of the wiring harness system under high frequency conditions to ensure that the system does not generate excessive electromagnetic interference to surrounding equipment. By limiting the radiation field strength within the set radiation limit, the system can be prevented from generating unnecessary radiation interference at high frequencies and improve electromagnetic compatibility performance. The second constraint is the limit on the crosstalk voltage |V xt (z,ω)| <V lim , where V lim is the set crosstalk limit. The crosstalk voltage reflects the electromagnetic coupling between adjacent high-frequency wires. A higher crosstalk voltage will increase the interference between adjacent wires. Therefore, by setting the limit of the crosstalk voltage, the mutual interference of high-frequency signals between different wires can be effectively controlled, thereby ensuring the signal integrity of the transmission line. The third constraint is the limit of shielding effectiveness SE(ω)>SE min , where SE min It is the minimum requirement for shielding effectiveness. Shielding effectiveness indicates the ability of the shielding layer to suppress high-frequency electromagnetic waves. A higher shielding effectiveness means that the shielding layer can effectively absorb or reflect electromagnetic waves and reduce the radiation intensity of electromagnetic interference. This constraint ensures that the design of the shielding layer can maintain sufficient shielding effectiveness under high-frequency conditions, thereby effectively suppressing the leakage of electromagnetic waves. The last constraint | Z c (ω)-Z0|<ΔZ max Used to control the deviation of characteristic impedance, where Z0 is the ideal characteristic impedance of the system, ΔZ maxIt is the allowable deviation range of characteristic impedance. The characteristic impedance of high-frequency wiring harness is an important parameter to maintain stability and matching during signal transmission. Unmatched impedance will lead to increased signal reflection and transmission loss. By controlling the deviation of characteristic impedance, the reflection and loss of the signal during transmission can be effectively reduced, ensuring that the high-frequency signal remains stable during transmission.

[0104] Based on these constraints, the objective function EMC is defined total , which is used to comprehensively measure the electromagnetic compatibility performance of the system. This objective function incorporates the radiation field strength, crosstalk voltage and shielding effectiveness into an overall evaluation system. Through integral calculation, the objective function weights and normalizes each indicator within the set frequency range (from ω1 to ω2) to form a comprehensive electromagnetic compatibility performance indicator. Specifically, the radiation field strength |E rad (ω)| 2 and crosstalk voltage |V xt (ω)| 2 The square of the limit and Normalization ensures that different performance indicators are compared in the same evaluation system. In addition, the shielding effectiveness SE(ω) is replaced by the target effectiveness SE ref Normalization is performed to ensure that the effect of the shielding layer at different frequencies can be accurately included in the evaluation system. The optimization goal of the objective function is to minimize EMC total , that is, reduce the impact of electromagnetic interference so that the system can achieve the best electromagnetic compatibility performance in a high-frequency environment. By minimizing this comprehensive performance indicator, all-round control of electromagnetic interference can be achieved. The integral calculation in the formula ensures the overall compatibility performance of the system within the set frequency range, rather than the electromagnetic characteristics of a single frequency point. By controlling the radiation, crosstalk and shielding effectiveness at different frequencies, the optimal design of full-band electromagnetic compatibility can be achieved. Ultimately, the combination of this objective function and constraints enables the system to ensure low radiation field intensity, small crosstalk effect and sufficient shielding effectiveness under high-frequency conditions through optimized design. The optimization results provide accurate data support for the design of new energy high-frequency wiring harnesses, enabling the system to operate while meeting all electromagnetic compatibility requirements.

[0105] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved. In addition, it is obvious that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. Multiple units or devices stated in the device claim can also be implemented by one unit or device through software or hardware. The words first, second, etc. are used to indicate names, and do not indicate any particular order.

Claims

1. A new energy high-frequency wiring harness design method based on electromagnetic compatibility optimization, characterized in that: The method comprises: Step 1: Establish an electromagnetic source model of the new energy high-frequency wire harness, and obtain the electromagnetic source intensity of the new energy high-frequency wire harness at each spatial point; based on the electromagnetic source intensity, calculate the electromagnetic field intensity in space; Step 2: Based on the spatial electromagnetic field intensity, calculate the equivalent transmission line parameters of the new energy high-frequency wire harness; based on the equivalent transmission line parameters, calculate the frequency-dependent characteristic impedance of the new energy high-frequency wire harness; Step 3: According to the frequency-dependent characteristic impedance, the crosstalk between adjacent wire harnesses in the new energy high-frequency wire harness is analyzed and the crosstalk voltage is calculated; according to the crosstalk voltage, the radiation field of the new energy high-frequency wire harness is calculated; according to the radiation field, the shielding effectiveness of the new energy high-frequency wire harness is calculated; Step 4: According to step 1, step 2 and step 3, set constraints, and establish an objective function under the constraints, and iteratively solve the objective function to find the optimal design parameter vector of the corresponding new energy high-frequency wiring harness; design the new energy high-frequency wiring harness through the optimal design parameter vector; the elements of the optimal design parameter vector include: the number of current sources, frequency-variable resistance, frequency-variable inductance, frequency-variable capacitance, frequency-variable conductance, shielding layer thickness and wiring harness current of the new energy high-frequency wiring harness.

2. The new energy high-frequency wiring harness design method based on electromagnetic compatibility optimization as claimed in claim 1 is characterized in that: In step 1, the electromagnetic source model of the new energy high-frequency wire harness is established by the following formula to obtain the electromagnetic source intensity of the new energy high-frequency wire harness at each spatial point: Where S(r,ω) represents the electromagnetic source intensity at a spatial point r at a given frequency ω; N is the number of current sources in the new energy high-frequency wire harness; i is an integer subscript index; I i is the current intensity of the i-th current source; is the attenuation factor of the current source intensity during spatial propagation, which simulates the inverse square attenuation characteristic of the distance from the current source to the spatial point; r i is the position vector of the i-th current source; t is the time variable; j is the negative sign; Represents the magnetization intensity M i (r) is the curl operation term; M i (r) is the magnetization at the i-th current source, × is the curl operator, which represents the effect of the magnetic field generated by the current source on the magnetization of the surrounding area.

3. The new energy high-frequency wiring harness design method based on electromagnetic compatibility optimization as described in claim 2 is characterized in that: In step 1, the electromagnetic field strength in space is calculated based on the electromagnetic source strength using the following formula: Where E(r,ω) represents the electromagnetic field intensity at a given frequency ω at a spatial point r; the skin depth δ(ω) defines the penetration depth of the electric field in the medium at the frequency ω; r' is the position integral variable; G(r,r') is the corresponding propagation Green's function under the position integral variable; S(r',ω) is the corresponding form of S(r,ω) under the position integral variable; V is the spatial range of the new energy high-frequency harness.

4. The new energy high-frequency wiring harness design method based on electromagnetic compatibility optimization as claimed in claim 3 is characterized in that: In step 2, the equivalent transmission line parameters of the new energy high-frequency wire harness are calculated based on the spatial electromagnetic field intensity using the following formula: in, is the equivalent transmission line parameter of the new energy high-frequency wiring harness; R(ω) is the frequency-dependent resistance at a given frequency ω; |E(r,ω)| is the modulus of the electric field intensity; σ c is the conductivity of the conductor of the new energy high-frequency wiring harness; C represents the closed path around the new energy high-frequency wiring harness; dl represents the distance integral variable on the closed path around the new energy high-frequency wiring harness; L(ω) is the frequency-variable inductance at a given frequency ω; μ0 is the vacuum permeability; d max is the diameter of the outer conductor of the new energy high-frequency wiring harness; d min is the diameter of the inner conductor of the new energy high-frequency wiring harness; μ r is the relative magnetic permeability of the new energy high-frequency wire harness, which indicates the magnetic permeability of the material of the new energy high-frequency wire harness relative to vacuum; ε r is the relative dielectric constant of the new energy high-frequency wire harness, which indicates the capacitance characteristics of the material of the new energy high-frequency wire harness relative to vacuum; ε0 is the dielectric constant of vacuum; C(ω) is the frequency-variable capacitance at a given frequency ω; G(ω) is the frequency-variable conductance at a given frequency ω; σ d is the conductivity of the medium.

5. The new energy high-frequency wiring harness design method based on electromagnetic compatibility optimization as described in claim 4 is characterized in that: In step 2, the frequency-dependent characteristic impedance of the new energy high-frequency wiring harness is calculated based on the equivalent transmission line parameters using the following formula: Among them, Z c (ω) is the frequency-dependent characteristic impedance at a given frequency ω; γ(ω) is the propagation constant at a given frequency ω; X is the length of the new energy high-frequency wiring harness.

6. The new energy high-frequency wiring harness design method based on electromagnetic compatibility optimization as claimed in claim 5 is characterized in that: In step 3, the crosstalk between adjacent wiring harnesses in the new energy high-frequency wiring harness is analyzed and the crosstalk voltage is calculated according to the frequency-dependent characteristic impedance using the following formula: Where Z0 is the nominal characteristic impedance; M 12 (ω) is the mutual inductance coefficient, which indicates the degree of electromagnetic coupling between two wire bundles. It is the mutual inductance of adjacent wire bundles at frequency ω; V xt (r,ω) is the crosstalk voltage at the spatial point r at a given frequency ω.

7. The new energy high-frequency wiring harness design method based on electromagnetic compatibility optimization as claimed in claim 6 is characterized in that: In step 3, the radiation field of the new energy high-frequency wiring harness is calculated based on the crosstalk voltage using the following formula: Among them, E rad (r,ω) represents the radiation field at the spatial point r at a given frequency ω after the shielding layer is installed; k is the wave number; k is the wave vector.

8. The new energy high-frequency wiring harness design method based on electromagnetic compatibility optimization as claimed in claim 7 is characterized in that: In step 3, the shielding effectiveness of the new energy high-frequency wiring harness is calculated based on the radiation field using the following formula: Among them, D is the thickness of the shielding layer of the new energy high-frequency wire harness; SE(ω) is the shielding effectiveness at frequency ω, in decibels; E0(r,ω) is the radiation field at the spatial point r at frequency ω when there is no shielding; α(ω) represents the attenuation constant at frequency ω, which determines the absorption intensity of the shielding layer to electromagnetic waves and is the set value.

9. The new energy high-frequency wiring harness design method based on electromagnetic compatibility optimization as claimed in claim 8 is characterized in that: In step 4, set the constraints using the following formula: |E rad (r,ω)| <E lim ; |V xt (z,ω)|<V lim ; SE(ω)>SE min ; |From c (ω)-Z0|<ΔZ max ; Among them, E lim is the set radiation limit; V lim is the set crosstalk limit; SE ref is the target shielding effectiveness; ΔZ max is the characteristic impedance threshold set; the objective function is defined as: min{EMC total }; Among them, ENC total is the performance index; ω1 is the set frequency lower limit; ω2 is the set frequency upper limit.

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