NEMP protection system, simulation method, medium and equipment

Abstract

The present application provides a NEMP protection system, a simulation method, a medium and a device, wherein the protection system comprises a primary protection unit, a secondary protection unit and a tertiary protection unit connected in series in sequence, wherein the primary protection unit comprises a shielded cable, the shielded cable is used for signal transmission at a signal transmitting end and / or a signal receiving end, and the shielding layer of the shielded cable is grounded; the secondary protection unit comprises a TVS tube limiter for reducing the amplitude of a pulse signal coupled to the cable; the tertiary protection unit comprises a T-type filter circuit for filtering out a pulse interference signal coupled to the cable.

Description

Technical Field

[0001] The present application relates to the field of electromagnetic pulse protection technology, and in particular to a NEMP protection system, simulation method, medium and equipment. Background Art

[0002] Nuclear Electromagnetic Pulse (NEMP) continues to attract attention due to its extremely destructive effect on electronic equipment. At present, foreign countries, especially the United States, have started relatively early in the study of NEMP effects and protection technologies. In China, a large amount of theoretical, numerical simulation and experimental work has been carried out on target coupling and device-level effects in the study of NEMP effects, but there are fewer studies on system-level effects and protection, and they are mainly experimental studies. Summary of the invention

[0003] In view of this, the present application provides a NEMP protection system, simulation method, medium and device, the main purpose of which is to effectively protect against NEMP.

[0004] According to one aspect of the present application, a NEMP protection system is provided, comprising a primary protection unit, a secondary protection unit and a tertiary protection unit connected in series in sequence, wherein:

[0005] The primary protection unit includes a shielded cable, which is used at the signal transmitting end and / or the signal receiving end for signal transmission, and the shielding layer of the shielded cable is grounded;

[0006] The secondary protection unit includes a TVS tube limiter for reducing the amplitude of the pulse signal coupled to the cable;

[0007] The three-stage protection unit includes a T-type filter circuit for filtering out pulse interference signals coupled to the cable.

[0008] In one implementation,

[0009] The signal transmitting end, the first-level protection unit, the second-level protection unit, the third-level protection unit, the first-level protection unit and the signal receiving end are connected in series in sequence, wherein the shielding layer of the shielded cable of the first-level protection unit connected to the signal transmitting end is grounded, and the shielding layer of the shielded cable of the first-level protection unit connected to the signal receiving end is grounded.

[0010] In one implementation,

[0011] The T-type filter circuit includes a first inductor, a second inductor and a capacitor, wherein the first inductor and the second inductor are connected in series, a first end of the capacitor is connected between the first inductor and the second inductor, and a second end of the capacitor is grounded.

[0012] According to one aspect of the present application, a NEMP protection method is provided, comprising:

[0013] Set up a first-level protection unit, a second-level protection unit and a third-level protection unit connected in series.

[0014] in,

[0015] The primary protection unit includes a shielded cable, which is used at the signal transmitting end and / or the signal receiving end for signal transmission, and the shielding layer of the shielded cable is grounded;

[0016] The secondary protection unit includes a TVS tube limiter for reducing the amplitude of the pulse signal coupled to the cable;

[0017] The three-stage protection unit includes a T-type filter circuit for filtering out pulse interference signals coupled to the cable.

[0018] In one implementation, the method further includes:

[0019] A double-end grounding of the shielded cable is set, wherein the signal transmitting end, the first-level protection unit, the second-level protection unit, the third-level protection unit, the first-level protection unit and the signal receiving end are connected in series in sequence, and the shielding layer of the shielded cable of the first-level protection unit of the signal transmitting end is grounded, and the shielding layer of the shielded cable of the first-level protection unit of the signal receiving end is grounded.

[0020] In one implementation,

[0021] The T-type filter circuit includes a first inductor, a second inductor and a capacitor, wherein the first inductor and the second inductor are connected in series, a first end of the capacitor is connected between the first inductor and the second inductor, and a second end of the capacitor is grounded.

[0022] According to one aspect of the present application, a NEMP protection simulation method is provided, which simulates NEMP protection of electronic equipment based on a field-circuit collaborative simulation system.

[0023] The simulation method comprises the following steps:

[0024] The shielded cable model is simulated and set in the three-dimensional field simulation model of the field-circuit collaborative simulation system, so that the shielding layer is grounded at both ends to complete the first-level protection;

[0025] The shielded cable model is converted into an equivalent circuit. In the two-dimensional circuit simulation model of the field-circuit collaborative simulation system, the simulation circuit is modeled based on the equivalent circuit. The TVS tube is used as a limiter for secondary protection to reduce the amplitude of the pulse signal coupled on the cable. The T-type filter circuit is used for tertiary protection to filter out the pulse interference signal coupled on the cable.

[0026] In one implementation,

[0027] In the simulation circuit, the signal transmitting end, the first-level protection unit, the second-level protection unit, the third-level protection unit, the first-level protection unit and the signal receiving end are connected in series in sequence, wherein the shielding layer of the shielded cable of the first-level protection unit connected to the signal transmitting end is grounded, and the shielding layer of the shielded cable of the first-level protection unit connected to the signal receiving end is grounded.

[0028] In one implementation,

[0029] The T-type filter circuit includes a first inductor, a second inductor and a capacitor, wherein the first inductor and the second inductor are connected in series, a first end of the capacitor is connected between the first inductor and the second inductor, and a second end of the capacitor is grounded.

[0030] In one implementation, the method further includes:

[0031] The field-circuit collaborative simulation system is constructed, and the field-circuit collaborative simulation system includes an electromagnetic structure, a mutual coupling interface and a circuit system. The result of the electromagnetic field analysis is equivalent from the electromagnetic structure to the circuit system through the mutual coupling interface.

[0032] According to one aspect of the present application, a storage medium is provided, in which a computer program is stored, wherein the computer program is configured to execute the above-mentioned NEMP protection simulation method when running.

[0033] According to one aspect of the present application, an electronic device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to execute the above-mentioned NEMP protection simulation method.

[0034] By means of the above technical scheme, the present application provides a NEMP protection system, simulation method, medium and equipment, and the protection system adopts three-level protection, specifically: first-level protection: the cables in the system use shielded cables, and the shielding layer of the shielded cables is grounded at both ends, so as to avoid differential mode interference caused by NEMP coupling; second-level protection: TVS tube is used as a limiter, the purpose is to reduce the amplitude of the pulse signal coupled to the cable; third-level protection: T-type filter circuit is established, the purpose is to filter out the pulse interference signal coupled to the cable. The NEMP protection system of the embodiment of the present application has multiple and efficient protections, which can effectively protect the circuit from the influence of electromagnetic pulses.

[0035] 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

[0036] 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:

[0037] Figure 1 A schematic diagram of the structure of a NEMP protection system provided in an embodiment of the present application is shown;

[0038] Figure 2 An example diagram of a NEMP protection system provided by an embodiment of the present application is shown;

[0039] Figure 3 A schematic diagram of the structure of a simulation system for NEMP protection simulation provided in an embodiment of the present application is shown;

[0040] Figure 4 A schematic diagram of a cross-section simulation of a shielded cable for NEMP protection simulation provided by an embodiment of the present application is shown;

[0041] Figure 5 A double-terminal grounding simulation of a shielding layer for NEMP protection simulation provided by an embodiment of the present application is shown;

[0042] Figure 6 A schematic diagram of a protection circuit in a CST of a NEMP protection simulation provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0043] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only embodiments of a part of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present application. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0044] As analyzed above, there is no effective solution for NEMP protection in China. In order to provide a NEMP protection system with good protection effect, low cost, and NEMP protection evaluation of the system in the design stage, the embodiment of the present application proposes a system-level NEMP protection system and simulation method. The NEMP protection system and simulation method provided in the embodiment of the present application can provide certain theoretical references and practical applications for NEMP protection work of drones, automobiles and other systems.

[0045] See also Figure 1 , shows a schematic diagram of the structure of a NEMP protection system provided in an embodiment of the present application. The NEMP protection system includes a primary protection unit, a secondary protection unit and a tertiary protection unit connected in series in sequence, wherein:

[0046] The primary protection unit includes a shielded cable, which is used at the signal transmitting end and / or the signal receiving end for signal transmission, and the shielding layer of the shielded cable is grounded;

[0047] The secondary protection unit includes a TVS tube limiter, which is used to reduce the amplitude of the pulse signal coupled to the cable;

[0048] The third-level protection unit includes a T-type filter circuit for filtering out pulse interference signals coupled to the cable.

[0049] See also Figure 2 , showing an example diagram of a NEMP protection system provided in an embodiment of the present application.

[0050] In the embodiment of the present application, a shielded cable is used for primary protection. A shielded cable, also known as a shielded cable, is a transmission line that uses a metal mesh braided layer to wrap the signal line. The braided layer is generally red copper or tinned copper. From the inside to the outside, the structure of the shielded cable may include a core wire, an inner insulating layer, a shielding layer, and an outer insulating layer.

[0051] Figure 2In the present invention, a first-level protection unit is used for protection at both the signal transmitting end and the signal receiving end, that is, shielded cables are used at both the signal transmitting end and the signal receiving end, and the shielding layer of the shielded cable is grounded, that is, the shielding layer of the shielded cable is grounded at both ends. Therefore, in one implementation, the signal transmitting end, the first-level protection unit, the second-level protection unit, the third-level protection unit, the first-level protection unit and the signal receiving end are connected in series in sequence, wherein the shielding layer of the shielded cable of the first-level protection unit connected to the signal transmitting end is grounded at both ends, and the shielding layer of the shielded cable of the first-level protection unit connected to the signal receiving end is grounded at both ends. The advantage of this treatment is that the nuclear electromagnetic pulse coupled on the cable is discharged by the method of double-end grounding of the shielding layer of the shielded wire, thereby improving the NEMP protection effect.

[0052] In the embodiment of the present application, a TVS tube is used as a limiter for secondary protection. The TVS (Transient Voltage Suppressor) transient voltage suppression diode is an overvoltage protection device with bidirectional voltage stabilization characteristics and bidirectional negative resistance characteristics, similar to a varistor. It is used in various AC and DC power supply circuits to suppress instantaneous overvoltages. When a surge pulse voltage appears instantly in the protected circuit, the bidirectional breakdown diode can quickly break down, changing from a high-resistance state to a low-resistance state, shunting and clamping the surge voltage, thereby protecting the various components in the circuit from being damaged by the instantaneous surge pulse voltage. Therefore, the TVS tube is used as a limiter in the embodiment of the present application in order to reduce the amplitude of the pulse signal coupled to the cable.

[0053] The embodiment of the present application adopts a T-type filter circuit for three-level protection. The T-type filter includes two inductors and a capacitor. Both ends of it are high impedance, and its insertion loss performance is similar to that of the π-type filter, but it is not prone to "ringing". Figure 2 The T-type filter circuit includes a first inductor L1, a second inductor L2 and a capacitor C, wherein the first inductor L1 and the second inductor L2 are connected in series, and a first end of the capacitor C is connected between the first inductor and the second inductor, and a second end of the capacitor C is grounded. The T-type filter circuit can effectively filter out the pulse interference signal coupled to the cable.

[0054] It can be seen that for the circuit system of the electronic device, the radiation interference of NEMP is caused during the transmission from the signal transmitting end to the receiving end. The embodiment of the present application provides a system-level NEMP protection system, which adopts three-level protection, specifically: Level 1 protection: the cables in the system use shielded cables, and the shielding layer of the shielded cables is grounded at both ends, so as to avoid the differential mode interference caused by NEMP coupling; Level 2 protection: TVS tube is used as a limiter, the purpose is to reduce the amplitude of the pulse signal coupled to the cable; Level 3 protection: T-type filtering circuit is established, the purpose is to filter out the pulse interference signal coupled to the cable. The NEMP protection system of the embodiment of the present application has multiple and efficient protections, which can effectively protect the circuit from the influence of electromagnetic pulses.

[0055] The embodiment of the present application also provides a NEMP protection method, which realizes multi-level protection of NEMP by setting a primary protection unit, a secondary protection unit and a tertiary protection unit connected in series in sequence.

[0056] in,

[0057] The primary protection unit includes a shielded cable, which is used at the signal transmitting end and / or the signal receiving end for signal transmission, and the shielding layer of the shielded cable is grounded;

[0058] The secondary protection unit includes a TVS tube limiter for reducing the amplitude of the pulse signal coupled to the cable;

[0059] The three-stage protection unit includes a T-type filter circuit for filtering out pulse interference signals coupled to the cable.

[0060] In one implementation, the method further includes:

[0061] The shielded cable is grounded at both ends, wherein the signal transmitting end, the first-level protection unit, the second-level protection unit, the third-level protection unit, the first-level protection unit and the signal receiving end are connected in series in sequence, and the shielding layer of the shielded cable of the first-level protection unit of the signal transmitting end is grounded at both ends, and the shielding layer of the shielded cable of the first-level protection unit of the signal receiving end is grounded at both ends.

[0062] In one implementation,

[0063] The T-type filter circuit includes a first inductor, a second inductor and a capacitor, wherein the first inductor and the second inductor are connected in series, a first end of the capacitor is connected between the first inductor and the second inductor, and a second end of the capacitor is grounded.

[0064] The following describes the modeling method of NEMP protection.

[0065] See also Figure 3, shows a schematic diagram of the structure of a simulation system for NEMP protection simulation provided in an embodiment of the present application.

[0066] In the embodiment of the present application, it is proposed to establish a NEMP protection simulation model by using the field-circuit coordination method of the CST simulation software. The field-circuit coordination simulation consists of a circuit system, an electromagnetic structure and its corresponding mutual coupling interface. The structure of the field-circuit coordination simulation is as follows: Figure 3 shown.

[0067] Field-circuit co-simulation is to equate the results of electromagnetic field analysis to the circuit, and finally complete the field-circuit co-simulation in circuit simulation software. Figure 3 The analysis of electromagnetic structure, i.e. "field", is mainly aimed at the electromagnetic radiation of electronic equipment and other issues. The modeling of the housing, cables, etc. of the electronic equipment is completed in the electromagnetic simulation software, and the full-wave model of the structure is calculated to obtain the field information stored in the three-dimensional field simulation model. The mutual coupling interface is the medium for the three-dimensional field simulation model to be converted into the circuit module in the two-dimensional circuit simulation model, realizing the bidirectional coupling between the full-wave simulation model and the simulation circuit. The three-dimensional solver CST Microwave Studio can calculate the S parameter matrix and quantify all the ports defined in the three-dimensional simulation. In the full-wave model, in order to maximize the transmission energy in the circuit, the port impedance defined in the model should be kept consistent. In the embodiment of the present application, the impedance of the port in the three-dimensional field simulation model can be set to 50Ω, for example. The circuit system can complete the construction of the two-dimensional circuit simulation model according to the topological structure of the actual circuit. Finally, the field-circuit collaborative simulation is realized in the circuit simulation module.

[0068] In the embodiment of the present application, the process of implementing modeling simulation using the field-circuit collaborative method of the CST simulation software is as follows:

[0069] First, the shielded cable model in the system is simulated and set in the three-dimensional field simulation model of the CST simulation software, so that the shielding layer is grounded at both ends to complete the first-level protection. The cross section of the shielded cable in CST is as follows: Figure 4 As shown in the figure, the simulation model of double-end grounding of the shield layer of the shielded cable is as follows Figure 5 As shown, from Figure 5 It can be seen that both the left and right ends of the shielding layer are grounded.

[0070] Then, the cable model is converted into an equivalent circuit. In the two-dimensional circuit simulation model of the CST simulation software, the simulation circuit is modeled based on the equivalent circuit. Specifically, in the secondary protection, the TVS tube is used as a limiter to reduce the amplitude of the pulse signal coupled to the cable; in the tertiary protection, the inductor L1 and L2 are connected with the capacitor C to form a T-type filter circuit to filter out the pulse interference signal coupled to the cable. The protection circuit simulation models of the secondary and tertiary protection are shown in Figure 1. Figure 6 shown.

[0071] In summary, the NEMP simulation system and simulation method provided in the embodiments of the present application provide system-level multiple protections through the primary protection of shielded cables, the secondary protection of TVS tubes, and the tertiary protection of T-type filter circuits, and can provide solutions for the NEMP protection of most systems. The corresponding simulation method can perform NEMP protection evaluation on the system during the design phase. In addition, the system-level NEMP protection system and simulation method provided in the embodiments of the present application are low-cost and high-efficiency.

[0072] An embodiment of the present application further provides a storage medium, in which a computer program is stored, wherein the computer program is configured to execute the steps of any of the above method embodiments when running.

[0073] Optionally, in this embodiment, the storage medium may be configured to store a computer program for performing the following steps:

[0074] Set up a first-level protection unit, a second-level protection unit and a third-level protection unit connected in series.

[0075] in,

[0076] The primary protection unit includes a shielded cable, which is used at the signal transmitting end and / or the signal receiving end for signal transmission, and the shielding layer of the shielded cable is grounded;

[0077] The secondary protection unit includes a TVS tube limiter for reducing the amplitude of the pulse signal coupled to the cable;

[0078] The three-stage protection unit includes a T-type filter circuit for filtering out pulse interference signals coupled to the cable.

[0079] Optionally, in this embodiment, the above-mentioned storage medium may include but is not limited to: a USB flash drive, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk, and other media that can store computer programs.

[0080] An embodiment of the present application further provides an electronic device, including a memory and a processor, wherein a computer program is stored in the memory, and the processor is configured to run the computer program to execute the steps in any one of the above method embodiments.

[0081] Optionally, the electronic device may further include a transmission device and an input / output device, wherein the transmission device is connected to the processor, and the input / output device is connected to the processor.

[0082] Optionally, in this embodiment, the processor may be configured to perform the following steps through a computer program:

[0083] Set up a first-level protection unit, a second-level protection unit and a third-level protection unit connected in series.

[0084] in,

[0085] The primary protection unit includes a shielded cable, which is used at the signal transmitting end and / or the signal receiving end for signal transmission, and the shielding layer of the shielded cable is grounded;

[0086] The secondary protection unit includes a TVS tube limiter for reducing the amplitude of the pulse signal coupled to the cable;

[0087] The three-stage protection unit includes a T-type filter circuit for filtering out pulse interference signals coupled to the cable.

[0088] Optionally, the specific examples in this embodiment may refer to the examples described in the above embodiments and optional implementation modes, and this embodiment will not be described in detail here.

[0089] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0090] In the above embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0091] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0092] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0093] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0094] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, disk or optical disk and other media that can store program codes.

[0095] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A NEMP protection system, characterized in that: It includes a primary protection unit, a secondary protection unit and a tertiary protection unit connected in series, wherein: The primary protection unit includes a shielded cable, which is used at the signal transmitting end and / or the signal receiving end for signal transmission, and the shielding layer of the shielded cable is grounded; The secondary protection unit includes a TVS tube limiter for reducing the amplitude of the pulse signal coupled to the cable; The three-stage protection unit includes a T-type filter circuit for filtering out pulse interference signals coupled to the cable.

2. The system according to claim 1, characterized in that The signal transmitting end, the first-level protection unit, the second-level protection unit, the third-level protection unit, the first-level protection unit and the signal receiving end are connected in series in sequence, wherein the shielding layer of the shielded cable of the first-level protection unit connected to the signal transmitting end is grounded, and the shielding layer of the shielded cable of the first-level protection unit connected to the signal receiving end is grounded.

3. The system according to claim 1 or 2, characterized in that: The T-type filter circuit includes a first inductor, a second inductor and a capacitor, wherein the first inductor and the second inductor are connected in series, a first end of the capacitor is connected between the first inductor and the second inductor, and a second end of the capacitor is grounded.

4. A NEMP protection method, characterized in that: include: Set up a first-level protection unit, a second-level protection unit and a third-level protection unit connected in series. in, The primary protection unit includes a shielded cable, which is used at the signal transmitting end and / or the signal receiving end for signal transmission, and the shielding layer of the shielded cable is grounded; The secondary protection unit includes a TVS tube limiter for reducing the amplitude of the pulse signal coupled to the cable; The three-stage protection unit includes a T-type filter circuit for filtering out pulse interference signals coupled to the cable.

5. The method according to claim 4, characterized in that Also includes: A double-end grounding of the shielded cable is set, wherein the signal transmitting end, the first-level protection unit, the second-level protection unit, the third-level protection unit, the first-level protection unit and the signal receiving end are connected in series in sequence, and the shielding layer of the shielded cable of the first-level protection unit of the signal transmitting end is grounded, and the shielding layer of the shielded cable of the first-level protection unit of the signal receiving end is grounded.

6. The method according to claim 4 or 5, characterized in that: The T-type filter circuit includes a first inductor, a second inductor and a capacitor, wherein the first inductor and the second inductor are connected in series, a first end of the capacitor is connected between the first inductor and the second inductor, and a second end of the capacitor is grounded.

7. A NEMP protection simulation method, characterized in that: Simulate NEMP protection of electronic equipment based on field-circuit collaborative simulation system. The simulation method comprises the following steps: The shielded cable model is simulated and set in the three-dimensional field simulation model of the field-circuit collaborative simulation system, so that the shielding layer is grounded at both ends to complete the first-level protection; The shielded cable model is converted into an equivalent circuit. In the two-dimensional circuit simulation model of the field-circuit collaborative simulation system, the simulation circuit is modeled based on the equivalent circuit. The TVS tube is used as a limiter for secondary protection to reduce the amplitude of the pulse signal coupled on the cable. The T-type filter circuit is used for tertiary protection to filter out the pulse interference signal coupled on the cable.

8. The method according to claim 7, characterized in that In the simulation circuit, the signal transmitting end, the first-level protection unit, the second-level protection unit, the third-level protection unit, the first-level protection unit and the signal receiving end are connected in series in sequence, wherein the shielding layer of the shielded cable of the first-level protection unit connected to the signal transmitting end is grounded, and the shielding layer of the shielded cable of the first-level protection unit connected to the signal receiving end is grounded.

9. A storage medium, characterized in that: The storage medium stores a computer program, wherein the computer program is configured to execute the method according to any one of claims 4 to 8 when executed.

10. An electronic device comprising a memory and a processor, characterized in that: A computer program is stored in the memory, and the processor is configured to run the computer program to perform the method according to any one of claims 4 to 8.

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