Shielding cable shielding layer terminating mode simulation optimization method and related equipment

Abstract

The invention discloses a shielding cable shielding layer terminating mode simulation optimization method and related equipment. The method comprises the following steps: constructing a cable simulation model of a shielding cable in a three-dimensional space according to material attribute data and physical attribute data of the shielding cable to be optimized; building an equivalent circuit for the cable simulation model in a two-dimensional space according to various terminating and grounding combination modes of a shielding layer in the shielding cable to obtain a field-circuit cooperation model of the cable simulation model according to different terminating and grounding combination modes; different forms of electromagnetic interference excitation are injected into the field-circuit cooperation model so as to carry out electromagnetic interference simulation on the field-circuit cooperation model. Therefore, by simulating the electromagnetic coupling effect when the shielding layer of the shielding cable adopts different terminating and grounding combination modes under electromagnetic interference, the design of the shielding cable in the shielding cable in an actual scene is guided, the dependence on later EMC test rectification is avoided, and the real object trial and error and repeated test cost is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of shielded cable design, and in particular to a method for simulating and optimizing termination of shielded cable shielding layers and related equipment. Background Art

[0002] To prevent cable signals from propagating into space and causing electromagnetic interference or information security issues, and to prevent electromagnetic energy in space from coupling to cables and interfering with termination devices, shielded cables are widely used in engineering to improve their electromagnetic compatibility (EMC) performance.

[0003] However, the choice of termination method for the shielding layer in shielded cables is often difficult to determine through theoretical analysis in the early design. If problems are found during the subsequent EMC testing of the actually produced shielded cables and then rectification is carried out, it will not only affect the project development cycle, but also increase the testing cost. Summary of the Invention

[0004] In view of this, the present application provides a simulation optimization method and related equipment for the termination method of the shielded layer of a shielded cable. By simulating the electromagnetic coupling effect when the shielded layer of the shielded cable adopts different termination and grounding combinations under electromagnetic interference, it guides the design of the termination method of the shielded layer of the shielded cable in actual scenarios.

[0005] According to one aspect of the present application, a method for simulating and optimizing the termination mode of a shielded cable shield layer is provided, comprising:

[0006] Constructing a cable simulation model of the shielded cable in three-dimensional space according to the material property data and the physical property data of the shielded cable;

[0007] According to various termination and grounding combinations of the shielding layer in the shielded cable, an equivalent circuit is constructed for the cable simulation model in a two-dimensional space to obtain a field-circuit coordination model of the cable simulation model according to the different termination and grounding combinations;

[0008] Injecting different forms of electromagnetic interference excitation into the field-circuit collaborative model to perform electromagnetic interference simulation on the field-circuit collaborative model;

[0009] According to the simulation results of the field-circuit synergy model under the electromagnetic interference excitation, a target termination method of the shielding layer in the shielded cable is determined, so as to optimize the shielded cable according to the target termination method.

[0010] According to another aspect of the present application, a device for simulating and optimizing the termination mode of a shielded cable shield layer is provided, comprising:

[0011] A construction module, configured to construct a cable simulation model of the shielded cable in three-dimensional space based on the material property data and physical property data of the shielded cable; and

[0012] According to various termination and grounding combinations of the shielding layer in the shielded cable, an equivalent circuit is constructed for the cable simulation model in a two-dimensional space to obtain a field-circuit coordination model of the cable simulation model according to the different termination and grounding combinations;

[0013] a simulation module, configured to inject different forms of electromagnetic interference excitation into the field-circuit collaborative model to perform electromagnetic interference simulation on the field-circuit collaborative model;

[0014] A determination module is used to determine a target termination method of the shielding layer in the shielded cable according to the simulation results of the field-circuit collaborative model under the electromagnetic interference excitation, so as to optimize the shielded cable according to the target termination method.

[0015] According to another aspect of the present application, a readable storage medium is provided, on which a program or instruction is stored. When the program or instruction is executed by a processor, the steps of the above-mentioned shielded cable shielding layer termination simulation optimization method are implemented.

[0016] According to another aspect of the present application, a computer device is provided, including a storage medium, a processor, and a computer program stored on the storage medium and executable on the processor. When the processor executes the program, the steps of the above-mentioned method for simulating and optimizing the termination method of the shielded cable shielding layer are implemented.

[0017] By means of the above technical solution, the present application provides a method and related equipment for simulating and optimizing the termination mode of the shielded cable shield layer, constructing a cable simulation model of the shielded cable to be optimized in three-dimensional space, and building an equivalent circuit for the cable simulation model in two-dimensional space according to the various termination and grounding combinations of the shielding layer in the shielded cable, effectively interacting the three-dimensional cable simulation model with the two-dimensional equivalent circuit, and obtaining a field-path synergistic model of the cable simulation model according to different termination and grounding combinations, accurately presenting the electromagnetic distribution of the shielded cable in three-dimensional space, while reducing the computational complexity through two-dimensional modeling. Further, in a virtual environment, the field-path synergistic model is used to simulate the electromagnetic coupling effect of the shielding layer in the shielded cable under different electromagnetic interference forms when different termination and grounding methods are adopted, without relying on physical testing, thereby improving test efficiency. Thus, the termination mode that makes the shielded cable shielding effect the best is screened out through the simulation results, the anti-interference ability and radiation suppression ability of the shielded cable are improved, the design of the shielded cable in the actual scene is guided, and the shielded cable actually produced meets the EMC standard, avoiding reliance on later EMC testing and rectification, and reducing the cost of physical trial and error and repeated testing.

[0018] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0020] Figure 1 A schematic structural diagram of the shielding layer lead termination provided in an embodiment of the present application is shown;

[0021] Figure 2 A schematic diagram of the structure of the circumferential connection of the shielding layer provided in an embodiment of the present application is shown;

[0022] Figure 3 A schematic diagram of the structure of the shielding layer cable clamp termination provided in an embodiment of the present application is shown;

[0023] Figure 4 A schematic diagram of a process for simulating and optimizing the termination mode of shielded cable shielding layers provided in an embodiment of the present application is shown;

[0024] Figure 5 A schematic diagram of the process of three-dimensional modeling of a shielded cable provided in an embodiment of the present application is shown;

[0025] Figure 6 A schematic structural diagram of a field-circuit coordination model of a cable simulation model provided in an embodiment of the present application when the shielding layer is circumferentially connected and grounded at both ends is shown;

[0026] Figure 7 A schematic structural diagram of a field-circuit coordination model of a cable simulation model provided in an embodiment of the present application when both ends of the shielding layer lead are grounded is shown;

[0027] Figure 8 A schematic diagram of the structure of the injection probe excitation provided in an embodiment of the present application is shown;

[0028] Figure 9 shows a schematic diagram of an equivalent circuit of a shielded circuit provided in an embodiment of the present application;

[0029] Figure 10 A schematic diagram of a cross-section of a cable simulation model of a single-core wire provided in an embodiment of the present application is shown;

[0030] Figure 11 A schematic diagram of a cross-section of a cable simulation model of an RG58 coaxial cable provided in an embodiment of the present application is shown;

[0031] Figure 12 The simulation results of different grounding methods when the shielding layer of the RG58 coaxial line is terminated with a lead wire under plane wave irradiation provided by the embodiment of the present application are shown;

[0032] Figure 13 The simulation results of different grounding methods when the shielding layer of the RG58 coaxial line is connected circumferentially under plane wave irradiation provided by the embodiment of the present application are shown;

[0033] Figure 14 A structural block diagram of a device for simulating and optimizing the termination method of shielded cable shielding layers provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0034] The present application will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that, unless there is a conflict, the embodiments and features in the embodiments of the present application can be combined with each other.

[0035] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and are not to be construed as limiting the present application.

[0036] It will be understood by those skilled in the art that, unless expressly stated otherwise, the singular forms "a", "an", "said" and "the" used herein may also include the plural forms. It should be further understood that the term "comprising" used in the specification of this application refers to the presence of the described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when we refer to an element as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, or there may be intermediate elements. In addition, "connected" or "connected" as used herein may include wireless connection or wireless fusion. The term "and / or" used herein includes all or any unit and all combinations of one or more associated listed items.

[0037] Now, exemplary embodiments according to the present application will be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments may be implemented in a variety of different forms and should not be construed as being limited to the embodiments set forth herein. It should be understood that these embodiments are provided to make the disclosure of this application thorough and complete and to fully convey the concepts of these exemplary embodiments to those of ordinary skill in the art.

[0038] With the development of modern science and technology, the electromagnetic environment in which electronic equipment operates has become increasingly complex, and the resulting electromagnetic interference (EMI) problem has become increasingly prominent. EMI propagation pathways include apertures, antennas, and cables, among other coupling methods. Cables are the foundation of all types of electromechanical equipment, serving as the carrier for transmitting energy and information.

[0039] Interconnect cables are highly efficient electromagnetic radiation transmitting antennas and highly efficient electromagnetic radiation sensitive receiving antennas. Theoretical and engineering practice indicate that most systems fail to meet EMC radiation test standards or generate radiated electromagnetic interference to surrounding electronic equipment, all due to electromagnetic radiation generated by the cables. The complexity of the structure, type, and layout paths of interconnect cables for electromechanical equipment further complicates their electromagnetic radiation and coupling mechanisms. To address electromagnetic interference issues with electronic equipment and improve their adaptability in complex electromagnetic environments, it is often necessary to shield sensitive cables in the system, creating shielded cables. However, the choice of termination method for the shield layer in shielded cables is often difficult to determine through theoretical analysis during early design. Rectifying issues that arise during subsequent EMC testing not only impacts the project development cycle but also increases testing costs.

[0040] It should be noted that the termination method refers to the physical connection form between the shielding layer and the grounding structure. For example, the termination methods include lead termination, circumferential connection (or 360-degree loop connection) and cable clamp connection. It is worth mentioning that in actual application scenarios, the shielding layer also inevitably involves the grounding method, so the termination method and the grounding method are analyzed together. The grounding method refers to the electrical connection state between the shielding layer and the grounding structure, including single-ended grounding (only one end of the shielding layer is grounded, and the other end is floating), double-ended grounding (both ends of the shielding layer are grounded), and floating (both ends of the shielding layer are not grounded, and it only exists as a shielding layer without a grounding connection). By combining different physical connection structures (termination methods) with different grounding states (grounding methods), a variety of shielding design schemes can be formed to adapt to different electromagnetic environments and engineering requirements.

[0041] Among them, Figure 1 As shown in the figure, lead termination refers to the process of spirally wrapping the shield layer of a shielded cable, leading a wire from the shield layer and connecting it to the ground structure. Lead termination concentrates the current in the shield layer on one side, which may reduce the shielding performance of the shielded cable. At high frequencies, the interference current in the shield layer and the inductance of the lead wire will generate a common-mode voltage on the shield layer at the termination location. This crosstalk will flow into the conductor and cause interference to the internal signal.

[0042] like Figure 2As shown in the figure, circumferential connection means that the shielding layer is 360 degrees overlapped with the grounding structure. When the shielded cable is introduced from or exported from the chassis port, the shielding layer of the shielded cable forms a firm all-round overlap with the chassis surface it passes through. This can fully prevent the interference current in the shielding layer from being conducted into the equipment. In EMC cable grounding design, this termination method is the most widely used, and cylindrical connectors are generally used to achieve the termination purpose of the shielded cable.

[0043] like Figure 3 As shown, cable clamp termination involves directly crimping the shield to the ground structure using a metal clamp. Cable clamp connections primarily use P-type clamps or 180-degree overlapped saddle clamps to connect the shield of a shielded cable to a housing or metal plate. This is a relatively ideal termination method.

[0044] Based on this, a simulation optimization method for shielded cable shield termination is provided in this embodiment, which simulates and analyzes the shield termination and grounding methods of shielded cables. By simulating the electromagnetic coupling effect of shielded cables with different termination and grounding methods under different electromagnetic interference forms, designers are guided in selecting the termination method of cable shields under electromagnetic interference. Figure 4 As shown, the method includes:

[0045] Step 401: construct a cable simulation model of the shielded cable in three-dimensional space based on the material property data and physical property data of the shielded cable.

[0046] In this embodiment, based on the material properties and physical properties of the shielded cable to be optimized, a cable simulation model of the shielded cable is constructed in three-dimensional space to restore the real physical properties of the actual shielded cable, ensure that the cable simulation model is consistent with the actual shielded cable, and provide a reliable basis for subsequent electromagnetic interference analysis.

[0047] Here, the shielded cable is three-dimensionally modeled mainly from three aspects: wire core, shielding layer and insulation layer.

[0048] Furthermore, as a refinement and expansion of the specific implementation methods of the above-mentioned embodiments, in order to fully illustrate the specific implementation process of this embodiment, a cable simulation model of the shielded cable is constructed in three-dimensional space based on the material property data and physical property data of the shielded cable, specifically including: obtaining the curve function or node coordinates corresponding to the shielded cable; in three-dimensional space, determining the cable path of the shielded cable according to the curve function or node coordinates; in three-dimensional space, based on the cable path, forming a cable simulation model of the shielded cable according to the material property data and physical property data of the shielded cable.

[0049] In this embodiment, Figure 5As shown, in a computer simulation technology (CST) operating environment, different modeling methods are selected, and the cable path of the shielded cable is obtained based on the selected modeling methods.

[0050] Here, we choose CST simulation software for 3D modeling. CST simulation software is a 3D electromagnetic field simulation software that includes multiple studio sub-software, such as CST Microwave Studio sub-software and CST Circuit Design Studio sub-software. The CST operating environment is the network operating environment corresponding to the CST simulation software.

[0051] For example, you can set the desired modeling mode in the 3D CST Microwave Studio. Modeling options include node modeling and curve modeling. For shielded cables with regular layouts, node modeling can be used. By setting the coordinates of the shielded cable's starting, intermediate, and ending nodes, a straight or simple curved cable path can be generated. Curve modeling can be used for shielded cables with curved, twisted, or irregular shapes. Curve modeling uses mathematical functions or parametric curves to generate complex cable paths.

[0052] Furthermore, the shielded cable may include at least one harness. A harness model may be obtained based on the node coordinates or curve functions corresponding to the harness. The harness models may be associated to form a cable model to simulate the cable clustering effect in actual wiring.

[0053] Then, based on the cable path as a geometric model, material properties (for example, insulation layer material, shielding layer material, core material, etc.) and physical properties (for example, electrical parameters, core thickness, shielding layer thickness, insulation layer thickness, shielding layer braiding angle, etc.) are set for the cable path respectively to form a cable simulation model of the shielded cable, so that the cable simulation model has real electromagnetic characteristics (such as skin effect, dielectric loss, etc.) and improves the simulation accuracy.

[0054] In step 402, an equivalent circuit is constructed for the cable simulation model in two-dimensional space according to various termination and grounding combinations of the shielding layer in the shielded cable, and a field-circuit coordination model of the cable simulation model according to different termination and grounding combinations is obtained.

[0055] In this embodiment, a variety of termination and grounding combinations are obtained based on the termination and grounding methods involved in the shielding layer of the shielded cable in actual application scenarios, thereby ensuring the comprehensiveness of the simulation.

[0056] Furthermore, in the CST Circuit Design Studio, corresponding two-dimensional equivalent circuits are constructed for different termination and grounding combinations of the shield layer. Through discrete ports or waveguide ports, these two-dimensional equivalent circuits interact and couple with the three-dimensional cable simulation model, forming a field-circuit synergy model for the cable simulation model under different termination and grounding combinations. By combining the three-dimensional spatial model with the two-dimensional equivalent circuit, the three-dimensional electromagnetic radiation characteristics and circuit transmission characteristics are analyzed, enabling accurate simulation of the electromagnetic coupling effects of shielded cables subjected to electromagnetic interference of different frequency bands under different termination and grounding combinations.

[0057] For example, the termination and grounding combination can include single-ended grounding of the lead (i.e., one end of the shielding layer is connected to the grounding structure through a wire), double-ended grounding of the lead (i.e., both ends of the shielding layer are connected to the grounding structure through a wire), floating ground of the lead (i.e., the wire led out from the shielding layer is not connected to the grounding structure), single-ended grounding of the circumferential connection (one end of the shielding layer is 360 degrees overlapped with the grounding structure), double-ended grounding of the circumferential connection (both ends of the shielding layer are 360 ​​degrees overlapped with the grounding structure), and floating ground of the circumferential connection (i.e., the shielded cable is not grounded).

[0058] For example, Figure 6 As shown, in the CST circuit design studio, for the combination of circumferential connection and double-end grounding, the electrical parameters between the shielding layer and the grounding structure are calculated when the shielding layer is circumferentially connected and grounded at both ends, and the electrical parameters are converted into circuit elements, so as to build a two-dimensional equivalent circuit corresponding to the case of the shielding layer being circumferentially connected and grounded at both ends on the basis of the three-dimensional cable simulation model 601, and then obtain the cable simulation model 601 when the shielding layer is circumferentially connected and grounded at both ends. Figure 6 The field-road collaborative model shown.

[0059] Similarly, if Figure 7 As shown, in the CST circuit design studio, for the combination of double-end grounding of the leads, the electrical parameters between the shielding layer and the grounding structure are calculated when the shielding layer leads are double-ended grounded, and the electrical parameters are converted into circuit elements, so as to build a two-dimensional equivalent circuit corresponding to the double-end grounding of the shielding layer leads on the basis of the three-dimensional cable simulation model 601, and then obtain the cable simulation model 601 according to the double-end grounding of the shielding layer leads. Figure 7 The field-road collaborative model shown.

[0060] The field-circuit coordination model of single-ended grounding and floating ground is Figure 6 and Figure 7 On the basis of the above, one end of the shield layer is grounded and both ends are not grounded.

[0061] Step 403 : injecting different forms of electromagnetic interference excitation into the field-circuit coordination model to perform electromagnetic interference simulation on the field-circuit coordination model.

[0062] In this embodiment, different forms of electromagnetic interference excitation are injected into the field-circuit collaborative model, and a field-circuit collaborative simulation combining three-dimensional and two-dimensional is performed to simulate the electromagnetic interference environment in actual application scenarios, verify the anti-interference ability of different termination and grounding combinations of the shielding layer in a complex electromagnetic environment, and cover a variety of interference scenarios.

[0063] For example, electromagnetic interference excitation can include common-mode interference and differential-mode interference. Common-mode interference can include plane wave excitation, injection probe excitation, and antenna excitation. Plane wave excitation uses a uniform plane electromagnetic wave as the interference source, injection probe excitation injects an electromagnetic interference excitation waveform directly into the cable via a current or voltage probe, and antenna excitation irradiates the cable with electromagnetic waves radiated by an antenna.

[0064] In this embodiment, the shielding effect of the shielding layer under different termination and grounding combinations is tested through simulation, which can be quickly evaluated in a virtual environment, reducing the cost and time of physical testing.

[0065] Furthermore, as a refinement and expansion of the specific implementation methods of the above-mentioned embodiments, in order to fully illustrate the specific implementation process of this embodiment, different forms of electromagnetic interference excitation are injected into the field-circuit collaborative model, specifically including: constructing an electromagnetic interference excitation source equivalent model based on the application scenario data of the shielded cable; building an interference source injection configuration model of the cable simulation model in three-dimensional space; using the electromagnetic interference excitation source equivalent model, injecting the waveform corresponding to the electromagnetic interference excitation into the cable simulation model in the field-circuit collaborative model through the interference source injection configuration model.

[0066] In this embodiment, based on the actual application scenarios of shielded cables, an electromagnetic interference excitation source equivalent model is abstracted so that the electromagnetic interference excitation source equivalent model can output different types of electromagnetic interference excitation waveforms in actual application scenarios, simulate real interference, ensure that the simulation environment is close to reality, and improve the credibility of the simulation results.

[0067] Furthermore, in the CST Microwave Studio, an interference source injection configuration model was built for the cable simulation model. The interference source injection configuration model was used as the transmission path for the electromagnetic interference excitation waveform output by the electromagnetic interference excitation source equivalent model, and the cable interference injection method was precisely controlled to ensure that the simulation conditions were repeatable and verifiable.

[0068] Then, the electromagnetic interference excitation source equivalent model is controlled to output different types of electromagnetic interference excitation waveforms, and the electromagnetic interference excitation waveforms are injected into the cable simulation model in the field-circuit collaborative model through the interference source injection configuration model, so as to perform simulation tests of different forms of electromagnetic interference on shielded cables with different termination and grounding combinations of the shielding layer. This does not require relying on physical testing, covers a variety of interference scenarios, and ensures the comprehensiveness of the simulation test.

[0069] For example, Figure 8 As shown, Figure 8 Only the three-dimensional cable simulation model within the field-circuit synergy model is shown. Taking injection probe excitation as an example, probe 801, acting as an interference source injection configuration model, is placed on cable simulation model 601. Probe 801 is provided with a feed port 802. If the electromagnetic wave output by the control electromagnetic interference excitation source equivalent model is a sine wave, probe 801 injects the sine wave from feed port 802 into cable simulation model 601, thereby causing electromagnetic interference to cable simulation model 601.

[0070] In one embodiment, the simulation optimization method for the termination method of the shielded cable shielding layer also includes: using the moment method to calculate the target electrical parameters of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation; constructing a cable equivalent circuit of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation based on the target electrical parameters; obtaining the voltage information or current information coupled by the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation based on the cable equivalent circuit, and using the voltage information or current information as the simulation result of the field-circuit collaborative model under electromagnetic interference excitation.

[0071] In this embodiment, in the CST circuit design studio, a transmission line modeling method based on a two-dimensional field solver, for example, 2D TL Modeling, is used to mesh the cross section of the cable simulation model in the field-circuit collaborative model. Based on the divided cable simulation model, the method of moments (MoM) is used to calculate the target electrical parameters of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation. Then, the target electrical parameters are converted into circuit elements, and a cable equivalent circuit of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation is constructed to accurately describe the transmission characteristics of the shielded cable under high-frequency conditions through the cable equivalent circuit.

[0072] Here, the accuracy and computational complexity of the two-dimensional modeling of the cable simulation model after electromagnetic interference excitation can be controlled by setting the grid accuracy (such as normal, medium, high, and very high), thereby reducing the computational complexity to quickly analyze and optimize the cable structure.

[0073] It should be noted that in the process of 2D modeling of the cable simulation model after electromagnetic interference excitation interference, not only can the skin effect of the conductor be considered to calculate the frequency-dependent resistance and inductance changes, but the loss angle of the dielectric material can also be considered to simulate the impact of dielectric loss on transmission characteristics. At the same time, different coupling modes can be selected, including no coupling, unidirectional coupling, and bidirectional coupling. In the case of no coupling, only the cable equivalent circuit is generated, and it is not coupled with the three-dimensional space solver. In the case of unidirectional coupling, the cable equivalent circuit can act as a field source (radiation) or a field receiver (irradiation). In the case of bidirectional coupling, the cable equivalent circuit acts as both a field source and a field receiver, which is suitable for strong interaction scenarios. In addition, it supports a variety of conductor shapes (such as circular and rectangular) and dielectric materials, improving the comprehensiveness of 2D modeling.

[0074] Next, the cable equivalent circuit is interacted with the original equivalent circuit in the field-circuit collaborative model to analyze the electromagnetic interaction between the shielded cable and the surrounding structure, and further simulation analysis is performed to calculate the voltage information or current information coupled by the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation, thereby obtaining the voltage / current information coupled on the shielded cable when the shielding layer adopts different termination and grounding combinations under different constructed electromagnetic interferences, and the voltage information or current information is used as the simulation result of the field-circuit collaborative model under electromagnetic interference excitation.

[0075] Furthermore, as a refinement and expansion of the specific implementation methods of the above-mentioned embodiments, in order to fully illustrate the specific implementation process of this embodiment, the target electrical parameters include impedance and admittance, and the moment method is used to calculate the target electrical parameters of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation, specifically including: determining the impedance of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation based on the equivalent resistance and parasitic inductance of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation; determining the admittance of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation based on the susceptance and distributed capacitance of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation.

[0076] In this embodiment, Figure 9 As shown in the figure, based on 2D TL Modeling, the electrical parameters such as capacitance, inductance, impedance and admittance of the cable simulation model in the field-circuit collaborative model are calculated, and these electrical parameters are equivalent to circuit elements to accurately describe the transmission characteristics of the shielded cable under high-frequency conditions. Based on these circuit elements, the three-dimensional cable simulation model in the field-circuit collaborative model is equivalent to a two-dimensional circuit model. Figure 9 In the figure, N1 and N2 represent the two ends of the shielded cable, R 11 is the equivalent resistance of the shielded cable, L 11 is the parasitic inductance of the shielded cable, C 11is the distributed capacitance of the shielded cable, G 11 is the susceptance of the shielded cable.

[0077] It's worth noting that 3D cable simulation models need to consider the electromagnetic distribution of the cable in three-dimensional space, involving extensive spatial meshing and solving complex electromagnetic equations, which is computationally intensive. In contrast, 2D equivalent circuit models focus solely on circuit parameters and signal transmission relationships, significantly reducing the computational effort and computation time.

[0078] Specifically, for each form of electromagnetic interference excitation, based on 2D TL Modeling, the moment method is used to calculate the impedance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation according to the equivalent resistance and parasitic inductance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation. In addition, based on the susceptance and distributed capacitance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation, the admittance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation is determined. Furthermore, the target electrical parameters such as the impedance and admittance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation are equivalent to circuit elements, so that the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation is converted into a two-dimensional cable equivalent circuit based on these circuit elements, thereby improving the simulation efficiency of electromagnetic interference.

[0079] For example, for any electromagnetic interference excitation, Z = R + J·ω·L, Y = G + J·ω·C. Among them, R is the equivalent resistance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation, J is the imaginary part, J·ω is the complex form of the angular frequency, L is the parasitic inductance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation, and Z is the impedance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation. G is the susceptance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation, C is the distributed capacitance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation, and Y is the admittance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation. It can be seen that the calculation difficulty is much lower than that of multi-dimensional.

[0080] Step 404 : determining a target termination method for the shielding layer of the shielded cable according to the simulation results of the field-circuit synergy model under electromagnetic interference excitation, so as to optimize the shielded cable according to the target termination method.

[0081] In this embodiment, based on the simulation results of the field-circuit synergy model under electromagnetic interference excitation, the electromagnetic coupling effect of the shielded cable's shield layer using different termination and grounding combinations under different electromagnetic interference conditions is obtained, thereby guiding designers in selecting cable shield termination methods under electromagnetic interference. This embodiment can not only optimize the selection of cable shield termination methods for different types of electromagnetic interference, but also be applied to different products and application scenarios, reducing the subsequent product rectification cycle and improving product design efficiency.

[0082] Furthermore, as a refinement and expansion of the specific implementation methods of the above-mentioned embodiments, in order to fully illustrate the specific implementation process of this embodiment, the simulation results of the field-circuit collaborative model under electromagnetic interference excitation include the voltage information or current information coupled by the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation. According to the simulation results of the field-circuit collaborative model under electromagnetic interference excitation, the target termination method of the shielding layer in the shielded cable is determined, specifically including: sorting the simulation results according to the peak value of the voltage information or current information to obtain a simulation order; according to the simulation order, screening out the target termination method of the shielding layer in the shielded cable from a variety of termination and grounding combinations.

[0083] In this embodiment, the voltage and current information coupled to the cable simulation model within the field-circuit collaboration model, when the field-circuit collaboration model is subjected to electromagnetic interference excitation, is used as the simulation result of the field-circuit collaboration model under the electromagnetic interference excitation. A larger peak value in the voltage or current information indicates a greater voltage or current coupled to the shielded cable by the electromagnetic interference, indicating a poorer shielding effectiveness of the shielding layer.

[0084] Furthermore, all simulation results are quantitatively compared based on the peak values ​​of the voltage or current information in the simulation results to determine a simulation sequence. This simulation sequence allows for a visual assessment of the impact of different termination and grounding methods on the shielding effectiveness of the shielded cable under varying levels of electromagnetic interference, eliminating subjective judgments. Based on the simulation sequence, the optimal termination method for the shielding effectiveness is selected from a variety of termination and grounding combinations, based on the requirements of actual application scenarios. This is the target termination method for the shielded cable's shielding layer. This target termination method guides design optimization and improves the cable's EMC performance.

[0085] In one embodiment, the shielded cable uses an RG58 coaxial cable, and in the lead termination method, the lead wire of the shield layer in the shielded cable uses an 8AWG single wire. It is worth mentioning that in this embodiment, in addition to establishing a cable simulation model for the shielded cable, a simulation model for an 8AWG single-core wire is also established for comparison to clarify how much current the single-core wire can couple without a shield layer. Then, through the cable simulation model, it is clarified how much current can be coupled with a shield layer on the basis of the single-core wire. By comparing the coupling current of the single-core wire and the shielded cable, not only can the necessity of the shield layer be verified, but the actual effectiveness of different termination and grounding combinations can also be accurately evaluated.

[0086] Among them, the cross-sections of the cable simulation models of single-core wire and RG58 coaxial cable as shielded cables are as follows: Figure 10 and Figure 11 The total length of the single-core cable and RG58 coaxial cable is 1m. The length of the shielded wire of the RG58 coaxial cable is 0.9m, and the length of the lead wires on both sides is 0.05m. The cable height from the ground is 50mm. The cables are placed in parallel with a spacing of 50mm.

[0087] Furthermore, with the RG58 coaxial cable as the shielded cable to be optimized, a two-dimensional equivalent circuit is built for the cable simulation model of the RG58 coaxial cable according to various termination and grounding combinations of the shielding layer in the RG58 coaxial cable, and the field-path coordination model of the cable simulation model of the RG58 coaxial cable is obtained according to different termination and grounding combinations.

[0088] Next, we take the plane wave irradiation of the field-circuit synergy model of the RG58 coaxial cable and the single-core cable simulation model as an example. The plane wave is incident vertically from above the cable, and the plane wave excitation is the CST default Gaussian pulse excitation. The field-circuit synergy simulation is performed to obtain the time domain current information of the coupling when the RG58 coaxial cable shield adopts different termination and grounding combinations under plane wave irradiation, as shown in the figure. Figure 12 and Figure 13 As shown. Among them, Figure 12 and Figure 13 The grounding method is used as a variable. Figure 12 The figure shows the effect of different grounding methods on the shielding effect when the shielding layer of RG58 coaxial line is terminated with lead under plane wave irradiation. Figure 13 The figure shows the effect of different grounding methods on the shielding effect when the shielding layer of the RG58 coaxial cable adopts a circumferential connection (i.e., 360-degree ring connection) under plane wave irradiation.

[0089] from Figure 12 and Figure 13 It can be seen that when the shielding layer of the RG58 coaxial cable is grounded at both ends, the shielding effect of the 360-degree ring connection is much better than the lead grounding. When the termination method of the shielding layer is determined, the shielding effects of single-ended grounding and floating ground are both poor, and the shielding effect is obvious only when the two ends are grounded.

[0090] It should be noted that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0091] Further, if Figure 14 As shown, as a specific implementation of the above-mentioned shielded cable shielding layer termination method simulation optimization method, an embodiment of the present application provides a shielded cable shielding layer termination method simulation optimization device 1400, and the shielded cable shielding layer termination method simulation optimization device 1400 includes: a construction module 1401, a simulation module 1402 and a determination module 1403.

[0092] The construction module 1401 is configured to construct a cable simulation model of the shielded cable in three-dimensional space based on the material property data and physical property data of the shielded cable; and to construct an equivalent circuit for the cable simulation model in two-dimensional space based on various termination and grounding combinations of the shielding layer in the shielded cable, thereby obtaining a field-circuit coordination model of the cable simulation model according to the different termination and grounding combinations.

[0093] A simulation module 1402 is configured to inject different forms of electromagnetic interference excitation into the field-circuit coordination model to perform electromagnetic interference simulation on the field-circuit coordination model;

[0094] The determination module 1403 is used to determine a target termination method of the shielding layer in the shielded cable according to the simulation results of the field-circuit synergy model under electromagnetic interference excitation, so as to optimize the shielded cable according to the target termination method.

[0095] In one embodiment, the simulation module 1402 is specifically used to construct an equivalent model of an electromagnetic interference excitation source based on the application scenario data of the shielded cable; to build an interference source injection configuration model of the cable simulation model in three-dimensional space; and to use the equivalent model of the electromagnetic interference excitation source to inject a waveform corresponding to the electromagnetic interference excitation into the cable simulation model in the field-circuit collaborative model through the interference source injection configuration model.

[0096] In one embodiment, the construction module 1401 is specifically used to obtain the curve function or node coordinates corresponding to the shielded cable; in three-dimensional space, the cable path of the shielded cable is determined according to the curve function or node coordinates; in three-dimensional space, based on the cable path, according to the material property data and physical property data of the shielded cable, a cable simulation model of the shielded cable is formed.

[0097] In one embodiment, the shielded cable shield termination mode simulation optimization method further includes:

[0098] The calculation module is used to calculate the target electrical parameters of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation by using the moment method; construct a cable equivalent circuit of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation based on the target electrical parameters; obtain the voltage information or current information coupled by the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation based on the cable equivalent circuit, and use the voltage information or current information as the simulation result of the field-circuit collaborative model under electromagnetic interference excitation.

[0099] In one embodiment, the calculation module is specifically used to determine the impedance of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation based on the equivalent resistance and parasitic inductance of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation; and determine the admittance of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation based on the susceptance and distributed capacitance of the cable simulation model in the field-circuit collaborative model under electromagnetic interference excitation.

[0100] In one embodiment, the determination module 1403 is specifically used to sort the simulation results according to the peak value of the voltage information or the current information to obtain a simulation order; according to the simulation order, the target termination method of the shielding layer in the shielded cable is screened out from a variety of termination and grounding combinations.

[0101] In one embodiment, the shielded cable shield termination mode simulation optimization method further includes:

[0102] The combination module is used for termination and grounding combination modes including single-end grounding of shield lead, double-end grounding of shield lead, floating ground of shield lead, single-end grounding of shield circumferential connection, double-end grounding of shield circumferential connection, and floating ground of shield circumferential connection.

[0103] Regarding the specific limitations of the device for simulating and optimizing the termination method of the shielded cable shield layer, please refer to the limitations of the method for simulating and optimizing the termination method of the shielded cable shield layer above, which will not be repeated here. The various modules in the above-mentioned device for simulating and optimizing the termination method of the shielded cable shield layer can be implemented in whole or in part through software, hardware, and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0104] Based on the above Figure 4 The method shown in FIG. 1 is a method for performing the above-mentioned operation. Accordingly, the embodiment of the present application further provides a readable storage medium having a computer program stored thereon. When the computer program is executed by the processor, the above-mentioned operation is performed. Figure 4 The simulation optimization method for shielded cable shield termination is shown.

[0105] Based on this understanding, the technical solution of the present application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, USB flash drive, mobile hard disk, etc.), including a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute the methods described in each implementation scenario of the present application.

[0106] Based on the above Figure 4 The method shown, and Figure 14 In order to achieve the above-mentioned purpose, the embodiment of the present application further provides a computer device, which can be a personal computer, a server, a network device, etc. The computer device includes a storage medium and a processor; the storage medium is used to store a computer program; the processor is used to execute the computer program to achieve the above-mentioned Figure 4 The simulation optimization method for shielded cable shield termination is shown.

[0107] Optionally, the computer device may further include a user interface, a network interface, a camera, a radio frequency (RF) circuit, a sensor, an audio circuit, a Wi-Fi module, etc. The user interface may include a display, an input unit such as a keyboard, etc., and the optional user interface may also include a USB interface, a card reader interface, etc. The network interface may optionally include a standard wired interface, a wireless interface (such as a Bluetooth interface, a Wi-Fi interface), etc.

[0108] Those skilled in the art will understand that the computer device structure provided in this embodiment does not constitute a limitation on the computer device, and may include more or fewer components, or a combination of certain components, or different component arrangements.

[0109] The storage medium may also include an operating system and a network communication module. An operating system is a program that manages and stores the hardware and software resources of a computer device, supporting the execution of information processing programs and other software and / or programs. The network communication module facilitates communication between components within the storage medium, as well as with other hardware and software within the physical device.

[0110] Through the description of the above implementation methods, those skilled in the art can clearly understand that the present application can be implemented with the help of software plus the necessary general hardware platform, and can also implement the embodiments of the present application through hardware.

[0111] Those skilled in the art will understand that the accompanying drawings are only schematic diagrams of a preferred implementation scenario, and the modules or processes in the accompanying drawings are not necessarily required to implement the present application. Those skilled in the art will understand that the modules in the devices in the implementation scenario can be distributed in the devices of the implementation scenario according to the implementation scenario description, or can be changed accordingly and located in one or more devices different from the implementation scenario. The modules of the above-mentioned implementation scenario can be combined into one module, or can be further split into multiple sub-modules.

[0112] The serial numbers of the above application are for descriptive purposes only and do not represent the advantages or disadvantages of the implementation scenarios. The above disclosure only discloses several specific implementation scenarios of the present application, but the present application is not limited thereto. Any changes that can be conceived by those skilled in the art should fall within the scope of protection of the present application.

Claims

1. A method for simulating and optimizing the termination mode of shielded cable shielding layer, characterized in that: The method comprises: Constructing a cable simulation model of the shielded cable in three-dimensional space according to the material property data and physical property data of the shielded cable to be optimized; According to various termination and grounding combinations of the shielding layer in the shielded cable, an equivalent circuit is constructed for the cable simulation model in a two-dimensional space to obtain a field-circuit coordination model of the cable simulation model according to the different termination and grounding combinations; Injecting different forms of electromagnetic interference excitation into the field-circuit collaborative model to perform electromagnetic interference simulation on the field-circuit collaborative model; According to the simulation results of the field-circuit synergy model under the electromagnetic interference excitation, a target termination method of the shielding layer in the shielded cable is determined, so as to optimize the shielded cable according to the target termination method.

2. The shielded cable shielding layer termination mode simulation optimization method according to claim 1, characterized in that: The injecting different forms of electromagnetic interference excitation into the field-circuit collaborative model specifically includes: Constructing an equivalent model of an electromagnetic interference excitation source based on application scenario data of the shielded cable; Building an interference source injection configuration model of the cable simulation model in three-dimensional space; The electromagnetic interference excitation source equivalent model is utilized and the interference source injection configuration model is used to inject a waveform corresponding to the electromagnetic interference excitation into the cable simulation model in the field-circuit collaborative model.

3. The method for simulating and optimizing the termination mode of shielded cable shielding layer according to claim 1, characterized in that: The constructing of a cable simulation model of the shielded cable in three-dimensional space based on the material property data and the physical property data of the shielded cable specifically includes: Obtaining a curve function or node coordinates corresponding to the shielded cable; In three-dimensional space, determining a cable path of the shielded cable according to the curve function or node coordinates; In three-dimensional space, based on the cable path and in accordance with the material property data and physical property data of the shielded cable, a cable simulation model of the shielded cable is formed.

4. The method for simulating and optimizing the termination mode of shielded cable shielding layer according to claim 1, characterized in that: The method further comprises: Calculating target electrical parameters of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation using the moment method; Constructing a cable equivalent circuit of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation according to the target electrical parameters; According to the cable equivalent circuit, voltage information or current information coupled by the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation is obtained, and the voltage information or current information is used as the simulation result of the field-circuit collaborative model under the electromagnetic interference excitation.

5. The method for simulating and optimizing the termination mode of shielded cable shielding layer according to claim 4, characterized in that: The target electrical parameters include impedance and admittance, and the method of calculating the target electrical parameters of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation by using the moment method specifically includes: Determining the impedance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation according to the equivalent resistance and parasitic inductance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation; The admittance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation is determined according to the susceptance and distributed capacitance of the cable simulation model in the field-circuit collaborative model under the electromagnetic interference excitation.

6. The method for simulating and optimizing the termination mode of shielded cable shielding layer according to claim 1, characterized in that: The simulation result of the field-circuit synergy model under the electromagnetic interference excitation includes voltage information or current information coupled by the cable simulation model in the field-circuit synergy model under the electromagnetic interference excitation. The determining of the target termination mode of the shielding layer in the shielded cable according to the simulation result of the field-circuit synergy model under the electromagnetic interference excitation specifically includes: sorting the simulation results according to the peak value of the voltage information or the current information to obtain a simulation order; According to the simulation sequence, a target termination method of the shielding layer in the shielded cable is screened out from the multiple termination and grounding combination methods.

7. The method for simulating and optimizing the termination mode of shielded cable shielding layer according to claim 1, characterized in that: The termination and grounding combination methods include single-end grounding of the shielding layer lead, double-end grounding of the shielding layer lead, floating ground of the shielding layer lead, single-end grounding of the shielding layer circumferential connection, double-end grounding of the shielding layer circumferential connection, and floating ground of the shielding layer circumferential connection.

8. A device for simulating and optimizing the termination mode of shielded cable shielding layer, characterized in that: The device comprises: A construction module, configured to construct a cable simulation model of the shielded cable in three-dimensional space based on the material property data and physical property data of the shielded cable; and According to various termination and grounding combinations of the shielding layer in the shielded cable, an equivalent circuit is constructed for the cable simulation model in a two-dimensional space to obtain a field-circuit coordination model of the cable simulation model according to the different termination and grounding combinations; a simulation module, configured to inject different forms of electromagnetic interference excitation into the field-circuit collaborative model to perform electromagnetic interference simulation on the field-circuit collaborative model; A determination module is used to determine a target termination method of the shielding layer in the shielded cable according to the simulation results of the field-circuit collaborative model under the electromagnetic interference excitation, so as to optimize the shielded cable according to the target termination method.

9. A readable storage medium having a program or instruction stored thereon, characterized in that: When the program or instruction is executed by a processor, the steps of the method for simulating and optimizing the termination mode of the shielded cable shield layer are implemented as described in any one of claims 1 to 7.

10. A computer device comprising a storage medium, a processor, and a computer program stored in the storage medium and executable on the processor, wherein: When the processor executes the program, the shielded cable shielding layer termination method simulation optimization method according to any one of claims 1 to 7 is implemented.

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