A method and system for analyzing electromagnetic radiation immunity of power battery BMS

Abstract

The present invention discloses a method and system for analyzing electromagnetic radiation immunity of a power battery BMS, including: obtaining a simulation platform model of a pre-established test bench, simulating a cable model based on the simulation platform model to obtain an external power line simulation current signal and a signal line simulation current signal of the BMS; using the simulation current signal as an excitation source for the external power line of a PCB circuit model, and using the signal line simulation current signal as an excitation source for the signal line of the PCB circuit model, simulating the PCB circuit model; judging whether the PCB circuit diagram meets the electromagnetic radiation immunity requirement according to the simulation result of the PCB circuit model. Through the present invention, it is possible to solve the problem that there is no special design specification to follow for electromagnetic compatibility performance related to electromagnetic immunity, so it is easy to fail the electromagnetic immunity test; and when the traditional BMS large current injection method immunity test fails, the technical problems of high PCB rectification cost, long cycle, and many iterations.

Description

Technical Field

[0001] The present invention relates to the technical field of power batteries, and in particular to a method and system for analyzing electromagnetic radiation immunity of a power battery BMS. Background Art

[0002] BMS (Battery Management System) is the abbreviation of the battery management system of the power battery. It monitors the voltage of each battery cell and the temperature of the module in the power battery, and manages the working status of the battery cell. It is regarded as one of the most critical components by vehicle manufacturers and component manufacturers. It is related to the service life of the power battery and the safety of the vehicle. All these put forward high requirements on the electromagnetic radiation immunity of BMS.

[0003] At present, the electromagnetic radiation immunity of BMS below 400MHz is tested by large current injection method in a shielded room, and the BMS function is normal and the interaction data is correct. In the design stage of the PCB circuit diagram file of BMS, the design is usually guided by the conventional PCB design specifications, and the wiring requirements are mainly proposed for power supply, clock and high-speed routing. There are no special design specifications to follow for electromagnetic compatibility performance related to electromagnetic immunity, so it is easy to fail the electromagnetic immunity test. Among them, in the field of electromagnetic simulation, since it is impossible to calculate the amplitude and phase of the interference signal current coupled to each cable in the BMS external cable through empirical formulas, the injected current can only be divided equally according to the number of BMS external cables, and evenly distributed to each cable, and the divided current is used as the interference signal to be introduced into the BMS under test through the cable to carry out relevant immunity simulation analysis.

[0004] When the BMS large current injection method immunity test fails, it is necessary to rectify the PCB board, modify the PCB circuit diagram, re-plate and assemble the PCB, and repeatedly modify and test the BMS, wasting a lot of time, manpower and material resources; and the coupling path of the interference signal in the PCB board is complex, and it is not easy to confirm the main coupling path of the interference that affects the sensitive source. The rectification cycle is long and the number of iterations is large. Summary of the invention

[0005] The purpose of the present invention is to propose a method and system for analyzing the electromagnetic radiation immunity of a power battery BMS, so as to solve the problem that there is no special design specification to follow for the electromagnetic compatibility performance related to electromagnetic immunity, so it is easy to fail the electromagnetic immunity test; and when the traditional BMS large current injection method immunity test fails, the PCB rectification cost is high, the cycle is long, and the number of iterations is large.

[0006] To achieve the above objectives, the present invention provides a method for analyzing the electromagnetic radiation immunity of a power battery BMS in a first aspect, comprising:

[0007] Obtain a PCB circuit diagram of the BMS, and establish a PCB circuit model according to the PCB circuit diagram;

[0008] Acquire external power line information and signal line information of the BMS, and establish a cable model according to the power line information and signal line information;

[0009] Acquire a pre-established simulation platform model of a test bench, and simulate the cable model based on the simulation platform model to obtain a simulated current signal of an external power line and a simulated current signal of a signal line of the BMS;

[0010] Using the simulated current signal as an excitation source for an external power line of the PCB circuit model, and using the signal line simulated current signal as an excitation source for a signal line of the PCB circuit model, to simulate the PCB circuit model;

[0011] Whether the PCB circuit diagram meets the electromagnetic radiation immunity requirement is determined according to the simulation result of the PCB circuit model.

[0012] Optionally, the simulation platform model is established according to the measurement requirements of the wire beam excitation method, including models of a low dielectric constant insulating support plate, a ground plane and a current clamp.

[0013] Optionally, simulating the cable model based on the simulation platform model to obtain an external power line simulation current signal and a signal line simulation current signal of the BMS includes:

[0014] Adjust the input power of the current clamp model excitation signal and perform frequency sweep in the frequency range of 1 MHz to 400 MHz so that the current amplitude tested in the cable model is consistent with the preset current value, and obtain the external power line simulation current signal and signal line simulation current signal of the BMS; wherein the power line simulation current signal and the signal line simulation current signal both include amplitude information and phase information.

[0015] Optionally, simulating the PCB circuit model includes:

[0016] The simulation current signal is introduced as an excitation source for the external power line of the PCB circuit model to the position of the external power line of the PCB circuit model, and the signal line simulation current signal is introduced as an excitation source for the signal line of the PCB circuit model to the position of the signal line of the PCB circuit model to perform simulation;

[0017] Obtaining the voltage collected by the voltage collection probe during the simulation of the PCB circuit model, comparing the voltage with a set limit value of the noise voltage that the BMS chip can withstand, and judging whether the BMS chip works normally according to the comparison result to obtain a simulation result;

[0018] Wherein, in the PCB circuit model, the voltage acquisition probe is arranged at the position of the BMS chip pin corresponding to the preset key signal.

[0019] Optionally, the method further comprises:

[0020] If it is determined that the PCB circuit diagram meets the electromagnetic radiation immunity requirement, the analysis process ends;

[0021] If it is determined that the PCB circuit diagram does not meet the electromagnetic radiation immunity requirement, the model parameters of the PCB circuit model are adjusted according to the simulation results, and the simulation is performed again until the simulation result shows that the PCB circuit model meets the electromagnetic radiation immunity requirement.

[0022] Optionally, adjusting the model parameters of the PCB circuit model according to the simulation results includes:

[0023] In the PCB circuit model, the wiring line width parameters, the wiring layout method or the decoupling capacitor value is adjusted so that the voltage at the location of the BMS chip pin corresponding to the preset key signal is less than the set limit of the noise voltage that the BMS chip can withstand.

[0024] A second aspect of the present invention provides a power battery BMS electromagnetic radiation immunity analysis system, the system comprising:

[0025] A PCB circuit model building unit, used to obtain a PCB circuit diagram of the BMS and build a PCB circuit model according to the PCB circuit diagram;

[0026] A cable model building unit, used to obtain external power line information and signal line information of the BMS, and build a cable model according to the power line information and signal line information;

[0027] A first simulation unit is used to obtain a simulation platform model of a pre-established test bench, and simulate the cable model based on the simulation platform model to obtain an external power line simulation current signal and a signal line simulation current signal of the BMS;

[0028] A second simulation unit is used to use the simulation current signal as an excitation source for an external power line of the PCB circuit model, and use the signal line simulation current signal as an excitation source for a signal line of the PCB circuit model to simulate the PCB circuit model;

[0029] A judging unit is used to judge whether the PCB circuit diagram meets the electromagnetic radiation immunity requirement according to the simulation result of the PCB circuit model.

[0030] Optionally, the simulation platform model is established according to the measurement requirements of the wire beam excitation method, and includes models of a low dielectric constant insulating support plate, a ground plane and a current clamp.

[0031] Optionally, the first simulation unit is specifically used to:

[0032] Adjust the input power of the current clamp model excitation signal and perform frequency sweep in the frequency range of 1 MHz to 400 MHz so that the current amplitude tested in the cable model is consistent with the preset current value, and obtain the external power line simulation current signal and signal line simulation current signal of the BMS; wherein the power line simulation current signal and the signal line simulation current signal both include amplitude information and phase information.

[0033] Optionally, the second simulation unit is specifically used to:

[0034] The simulation current signal is introduced as an excitation source for the external power line of the PCB circuit model into the position of the external power line of the PCB circuit model, and the signal line simulation current signal is introduced as an excitation source for the signal line of the PCB circuit model into the position of the signal line of the PCB circuit model to perform simulation; and the voltage collected by the voltage collection probe during the simulation of the PCB circuit model is obtained, the voltage is compared with the set limit value of the noise voltage that the BMS chip can withstand, and whether the BMS chip is working normally is determined according to the comparison result to obtain the simulation result;

[0035] Wherein, in the PCB circuit model, the voltage acquisition probe is arranged at the position of the BMS chip pin corresponding to the preset key signal.

[0036] The embodiments of the present invention provide a method and system for analyzing electromagnetic radiation immunity of a power battery BMS, which have at least the following beneficial effects:

[0037] (1) In view of the technical problems that the BMS fails the large current injection method immunity test, the PCB rectification cost is high, the cycle is long, and the number of iterations is large, the embodiments of the present invention can perform simulation modeling and analysis in the early stage of the PCB circuit diagram design of the BMS. When the simulation result shows that the PCB circuit model cannot work normally during the simulation process, that is, according to the simulation result of the PCB circuit model, it is judged that the PCB circuit diagram does not meet the electromagnetic radiation immunity requirement, the design parameters of the PCB circuit diagram model, such as the routing and decoupling capacitors, can be directly modified and adjusted quickly, thereby providing a fast and comprehensive analysis method for the electromagnetic immunity of the BMS;

[0038] (2) In order to address the disadvantage that evenly distributing the injected current to each cable is inconsistent with the actual situation and easily causes large errors, the simulation platform model and cable model in the embodiment of the present invention are consistent with the actual test layout, and can truly reflect the waveform amplitude and phase transformation from the current clamp injection signal port to each cable port of the BMS external cable, thereby ensuring the accuracy of the results of the BMS electromagnetic immunity analysis method.

[0039] Other features and advantages of the present invention will be set forth in the description which follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 The present invention is a flowchart of a method for analyzing electromagnetic radiation immunity of a power battery BMS in one embodiment of the present invention.

[0042] Figure 2 FIG. 4 is a schematic diagram of a partial structure of a cable model in one embodiment of the present invention.

[0043] Figure 3 FIG. 4 is a schematic diagram of a time domain waveform of an AM modulation signal in an embodiment of the present invention.

[0044] Figure 4 FIG. 4 is a schematic diagram of a time domain waveform of a CW signal in an embodiment of the present invention.

[0045] Figure 5 A schematic diagram of a severe level current value threshold in one embodiment of the present invention;

[0046] Figure 6 A schematic diagram of current amplitude tested in a single cable for adjusting input power in an embodiment of the present invention.

[0047] Figure 7 The figure is a schematic diagram of the structure of a power battery BMS electromagnetic radiation immunity analysis system in one embodiment of the present invention. DETAILED DESCRIPTION

[0048] Various exemplary embodiments, features and aspects of the present disclosure will be described in detail below with reference to the accompanying drawings. In addition, in order to better illustrate the present invention, numerous specific details are given in the specific embodiments below. It should be understood by those skilled in the art that the present invention can also be implemented without certain specific details. In some examples, means well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present invention.

[0049] See also Figure 1 An embodiment of the present invention provides a method for analyzing electromagnetic radiation immunity of a power battery BMS, comprising the following steps S1 to S5:

[0050] Step S1, obtaining a PCB circuit diagram of the BMS, and establishing a PCB circuit model according to the PCB circuit diagram;

[0051] Specifically, the PCB circuit diagram is a PCB layout designed during the research and development process. According to the PCB circuit diagram, a PCB circuit model for simulation can be established; used in the subsequent step S4;

[0052] Exemplarily, the PCB circuit diagram may include a main board and a slave board; or only a main board;

[0053] Step S2, obtaining external power line information and signal line information of the BMS, and establishing a cable model according to the power line information and signal line information;

[0054] Specifically, the cable model is a three-dimensional model, and the external power line information and signal line information of the BMS include the number and type of external power lines and signal lines; the established cable model is as follows Figure 2 As shown, specifically in Figure 2 In the example, one set of cables is differential, and the others are power cables and single-ended signal cables.

[0055] Step S3, obtaining a pre-established simulation platform model of a test bench, and simulating the cable model based on the simulation platform model to obtain an external power line simulation current signal and a signal line simulation current signal of the BMS;

[0056] Exemplarily, the simulation platform model is established according to the measurement requirements of the wire beam excitation method, including models of a low dielectric constant insulating support plate, a ground plane, and a current clamp;

[0057] Specifically, in this embodiment, according to the test standard of "ISO 11452-4 Road Vehicles. Test Method for Electronic Interference Components of Narrowband Radiated Electromagnetic Energy. Part 4: Harness Excitation Method", a simulation platform of the test bench is built, the size of the low dielectric constant insulating support plate is 2000mm*600mm*50mm, the size of the ground plane is 2000mm*1000mm*1mm, and the loss caused by the simplified model of the current clamp can be compensated by adjusting the input power. It is not necessary to strictly build the current clamp model according to the actual test device, and it is only necessary to ensure that all cables can be inserted;

[0058] Exemplarily, the step S3 specifically includes:

[0059] Adjust the input power of the current clamp model excitation signal, perform frequency sweeping in the frequency range of 1 MHz to 400 MHz, so that the current amplitude tested in the cable model is consistent with the preset current value, and obtain the external power line simulation current signal and signal line simulation current signal of the BMS; wherein the power line simulation current signal and the signal line simulation current signal both include amplitude information and phase information;

[0060] Specifically, according to the test standard "ISO11452-4 Road vehicles. Test methods for electronic interference components of narrow-band radiated electromagnetic energy. Part 4: Harness excitation method", the correct power source is selected according to the excitation signal type, usually AM wave or CW wave. For example, Figure 3 This is a schematic diagram of the time domain waveform of the AM modulation signal. Figure 3 Medium amplitude modulation coefficient = 0.8, modulation signal = 1kHz, carrier signal = 1MHz; Figure 4 This is a schematic diagram of the CW signal time domain waveform. Figure 4 Medium signal frequency = 100MHz;

[0061] In this implementation step S3, the input power of the current clamp model excitation signal is adjusted, and the frequency is swept in the frequency range of 1 MHz to 400 MHz, so that the current amplitude tested in a single cable is consistent with the level severity level current value of the replacement method in "ISO11452-4 Road vehicles. Test method for electronic interference components of narrow-band radiated electromagnetic energy. Part 4: Harness excitation method"; illustratively, Figure 5 This is a schematic diagram of the severe grade current value threshold; Figure 6 To adjust the input power, the current amplitude diagram is tested in a single cable. Figure 6 Where m1 is the current amplitude;

[0062] Step S4, using the simulated current signal as an excitation source for the external power line of the PCB circuit model, and using the signal line simulated current signal as an excitation source for the signal line of the PCB circuit model, to simulate the PCB circuit model;

[0063] Exemplarily, simulating the PCB circuit model includes:

[0064] Step S41, importing the simulation current signal as an excitation source for the external power line of the PCB circuit model into the position of the external power line of the PCB circuit model, and importing the signal line simulation current signal as an excitation source for the signal line of the PCB circuit model into the position of the signal line of the PCB circuit model, to perform simulation;

[0065] Step S42, obtaining the voltage collected by the voltage collection probe during the simulation of the PCB circuit model, comparing the voltage with the set limit value of the noise voltage that the BMS chip can withstand, and judging whether the BMS chip works normally according to the comparison result to obtain the simulation result;

[0066] Wherein, in the PCB circuit model, the voltage acquisition probe is arranged at the position where the BMS chip pin corresponding to the preset key signal is located;

[0067] It should be noted that the preset key signal refers to a key signal that has a greater impact on the electromagnetic immunity performance of the BMS, that is, a signal at a sensitive position, which may specifically include signals at multiple sensitive positions, which may be selected and determined by a specific PCB circuit structure when implementing the method of this embodiment. The PCB circuit diagram of the BMS is not listed here for introduction, because the PCB circuit diagram of the BMS is diverse, but based on the description of the method of this embodiment, it can be seen that the method of this embodiment is applicable to simulation tests of various PCB circuit structures of BMS;

[0068] It should also be noted that if the BMS includes a main board and a slave board, the excitation source needs to be imported into the power line position and signal line position of the main board and the slave board respectively;

[0069] Step S5: judging whether the PCB circuit diagram meets the electromagnetic radiation immunity requirement according to the simulation result of the PCB circuit model;

[0070] Optionally, the step S5 further includes:

[0071] If it is determined that the PCB circuit diagram meets the electromagnetic radiation immunity requirement, the analysis process ends;

[0072] If it is determined that the PCB circuit diagram does not meet the electromagnetic radiation immunity requirement, the model parameters of the PCB circuit model are adjusted according to the simulation results, and the above steps S1 to S4 are re-executed according to the adjusted PCB circuit model for simulation until the simulation result shows that the PCB circuit model meets the electromagnetic radiation immunity requirement;

[0073] Specifically, adjusting the model parameters of the PCB circuit model according to the simulation results includes:

[0074] In the PCB circuit model, the wiring line width parameters, the wiring layout method or the decoupling capacitor value is adjusted so that the voltage at the location of the BMS chip pin corresponding to the preset key signal is less than the set limit of the noise voltage that the BMS chip can withstand.

[0075] It can be seen from the description of the above embodiment method that the embodiment method of the present invention has the following advantages:

[0076] (1) In view of the technical problems that the BMS fails the large current injection method immunity test, the PCB rectification cost is high, the cycle is long, and the number of iterations is large, the embodiments of the present invention can perform simulation modeling and analysis in the early stage of the PCB circuit diagram design of the BMS. When the simulation result shows that the PCB circuit model cannot work normally during the simulation process, that is, according to the simulation result of the PCB circuit model, it is judged that the PCB circuit diagram does not meet the electromagnetic radiation immunity requirement, the design parameters of the PCB circuit diagram model, such as the routing and decoupling capacitors, can be directly modified and adjusted quickly, thereby providing a fast and comprehensive analysis method for the electromagnetic immunity of the BMS;

[0077] (2) In view of the disadvantage that evenly distributing the injected current to each cable is inconsistent with the actual situation and easily causes large errors, the simulation platform model and the cable model in the embodiment of the present invention are consistent with the actual test layout, and can truly reflect the waveform amplitude and phase transformation from the current clamp injection signal port to each cable port of the BMS external cable, thereby ensuring the accuracy of the results of the BMS electromagnetic immunity analysis method;

[0078] (3) The loss introduced by the simplified modeling of the current clamp can be compensated by adjusting the input power. There is no need to strictly build the current clamp model according to the actual current clamp device. It is only necessary to ensure that all cables can be inserted, which also ensures the effectiveness and practicality of the method of the embodiment of the present invention.

[0079] See also Figure 7 Another embodiment of the present invention provides a power battery BMS electromagnetic radiation immunity analysis system, which can be used to implement the power battery BMS electromagnetic radiation immunity analysis method described in the above embodiment. The system includes:

[0080] A PCB circuit model building unit 1 is used to obtain a PCB circuit diagram of the BMS and build a PCB circuit model according to the PCB circuit diagram;

[0081] The cable model building unit 2 is used to obtain the external power line information and signal line information of the BMS, and build a cable model according to the power line information and signal line information;

[0082] The first simulation unit 3 is used to obtain a simulation platform model of a pre-established test bench, and simulate the cable model based on the simulation platform model to obtain an external power line simulation current signal and a signal line simulation current signal of the BMS;

[0083] A second simulation unit 4 is used to use the simulation current signal as an excitation source for the external power line of the PCB circuit model, and use the signal line simulation current signal as an excitation source for the signal line of the PCB circuit model to simulate the PCB circuit model;

[0084] The judging unit 5 judges whether the PCB circuit diagram meets the electromagnetic radiation immunity requirement according to the simulation result of the PCB circuit model.

[0085] Optionally, the simulation platform model is established according to the measurement requirements of the wire beam excitation method, and includes models of a low dielectric constant insulating support plate, a ground plane and a current clamp.

[0086] Optionally, the first simulation unit 3 is specifically used to:

[0087] Adjust the input power of the current clamp model excitation signal and perform frequency sweep in the frequency range of 1 MHz to 400 MHz so that the current amplitude tested in the cable model is consistent with the preset current value, and obtain the external power line simulation current signal and signal line simulation current signal of the BMS; wherein the power line simulation current signal and the signal line simulation current signal both include amplitude information and phase information.

[0088] Optionally, the second simulation unit 4 is specifically used to:

[0089] The simulation current signal is introduced as an excitation source for the external power line of the PCB circuit model into the position of the external power line of the PCB circuit model, and the signal line simulation current signal is introduced as an excitation source for the signal line of the PCB circuit model into the position of the signal line of the PCB circuit model to perform simulation; and the voltage collected by the voltage collection probe during the simulation of the PCB circuit model is obtained, the voltage is compared with the set limit value of the noise voltage that the BMS chip can withstand, and whether the BMS chip is working normally is determined according to the comparison result to obtain the simulation result;

[0090] Wherein, in the PCB circuit model, the voltage acquisition probe is arranged at the position of the BMS chip pin corresponding to the preset key signal.

[0091] The system embodiment described above is merely illustrative, wherein 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 modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0092] It should be noted that the system described in the above embodiment corresponds to the method described in the above embodiment. Therefore, the undescribed part of the system described in the above embodiment can be obtained by referring to the content of the method described in the above embodiment. That is, the step limitation content of the method in the above embodiment should be understood as the functional content that can be achieved by the system of this embodiment, and will not be repeated here.

[0093] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A method for analyzing electromagnetic radiation immunity of a power battery BMS, characterized in that: include: Obtain a PCB circuit diagram of the BMS, and establish a PCB circuit model according to the PCB circuit diagram; Acquire external power line information and signal line information of the BMS, and establish a cable model according to the power line information and signal line information; Acquire a pre-established simulation platform model of a test bench, and simulate the cable model based on the simulation platform model to obtain a simulated current signal of an external power line and a simulated current signal of a signal line of the BMS; Using the simulated current signal as an excitation source for an external power line of the PCB circuit model, and using the signal line simulated current signal as an excitation source for a signal line of the PCB circuit model, to simulate the PCB circuit model; Determining whether the PCB circuit diagram meets the electromagnetic radiation immunity requirement according to the simulation result of the PCB circuit model; Wherein, simulating the PCB circuit model includes: The simulation current signal is introduced as an excitation source for the external power line of the PCB circuit model to the position of the external power line of the PCB circuit model, and the signal line simulation current signal is introduced as an excitation source for the signal line of the PCB circuit model to the position of the signal line of the PCB circuit model to perform simulation; Obtaining the voltage collected by the voltage collection probe during the simulation of the PCB circuit model, comparing the voltage with a set limit value of the noise voltage that the BMS chip can withstand, and judging whether the BMS chip works normally according to the comparison result to obtain a simulation result; Wherein, in the PCB circuit model, the voltage acquisition probe is arranged at the position of the BMS chip pin corresponding to the preset key signal.

2. The method for analyzing electromagnetic radiation immunity of a power battery BMS according to claim 1 is characterized in that: The simulation platform model is established according to the measurement requirements of the wire harness excitation method, and includes models of a low dielectric constant insulating support plate, a ground plane, and a current clamp.

3. The method for analyzing electromagnetic radiation immunity of a power battery BMS according to claim 2 is characterized in that: The simulating the cable model based on the simulation platform model to obtain an external power line simulation current signal and a signal line simulation current signal of the BMS includes: Adjust the input power of the current clamp model excitation signal and perform frequency sweep in the frequency range of 1 MHz to 400 MHz so that the current amplitude tested in the cable model is consistent with the preset current value, and obtain the external power line simulation current signal and signal line simulation current signal of the BMS; wherein the power line simulation current signal and the signal line simulation current signal both include amplitude information and phase information.

4. The method for analyzing electromagnetic radiation immunity of a power battery BMS according to claim 1, characterized in that: The method further comprises: If it is determined that the PCB circuit diagram meets the electromagnetic radiation immunity requirement, the analysis process ends; If it is determined that the PCB circuit diagram does not meet the electromagnetic radiation immunity requirement, the model parameters of the PCB circuit model are adjusted according to the simulation results, and the simulation is performed again until the simulation result shows that the PCB circuit model meets the electromagnetic radiation immunity requirement.

5. The method for analyzing electromagnetic radiation immunity of a power battery BMS according to claim 4 is characterized in that: The adjusting the model parameters of the PCB circuit model according to the simulation results includes: In the PCB circuit model, the wiring line width parameters, the wiring layout method or the decoupling capacitor value is adjusted so that the voltage at the location of the BMS chip pin corresponding to the preset key signal is less than the set limit of the noise voltage that the BMS chip can withstand.

6. A power battery BMS electromagnetic radiation immunity analysis system, characterized in that: The system comprises: A PCB circuit model building unit, used to obtain a PCB circuit diagram of the BMS and build a PCB circuit model according to the PCB circuit diagram; A cable model building unit, used to obtain external power line information and signal line information of the BMS, and build a cable model according to the power line information and signal line information; A first simulation unit is used to obtain a simulation platform model of a pre-established test bench, and simulate the cable model based on the simulation platform model to obtain an external power line simulation current signal and a signal line simulation current signal of the BMS; A second simulation unit is used to use the simulation current signal as an excitation source for an external power line of the PCB circuit model, and use the signal line simulation current signal as an excitation source for a signal line of the PCB circuit model to simulate the PCB circuit model; A judging unit, for judging whether the PCB circuit diagram meets the electromagnetic radiation immunity requirement according to the simulation result of the PCB circuit model; Wherein, the second simulation unit is specifically used for: The simulation current signal is introduced as an excitation source for the external power line of the PCB circuit model into the position of the external power line of the PCB circuit model, and the signal line simulation current signal is introduced as an excitation source for the signal line of the PCB circuit model into the position of the signal line of the PCB circuit model to perform simulation; and the voltage collected by the voltage collection probe during the simulation of the PCB circuit model is obtained, the voltage is compared with the set limit value of the noise voltage that the BMS chip can withstand, and whether the BMS chip is working normally is determined according to the comparison result to obtain the simulation result; Wherein, in the PCB circuit model, the voltage acquisition probe is arranged at the position of the BMS chip pin corresponding to the preset key signal.

7. The power battery BMS electromagnetic radiation immunity analysis system according to claim 6 is characterized in that: The simulation platform model is established according to the measurement requirements of the wire harness excitation method, and includes models of a low dielectric constant insulating support plate, a ground plane, and a current clamp.

8. The power battery BMS electromagnetic radiation immunity analysis system according to claim 7 is characterized in that: The first simulation unit is specifically used for: Adjust the input power of the current clamp model excitation signal and perform frequency sweep in the frequency range of 1 MHz to 400 MHz so that the current amplitude tested in the cable model is consistent with the preset current value, and obtain the external power line simulation current signal and signal line simulation current signal of the BMS; wherein the power line simulation current signal and the signal line simulation current signal both include amplitude information and phase information.

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