Method for determining a set of electromagnetic risk frequencies for a vehicle, storage medium and vehicle

Abstract

This application discloses a method for determining the electromagnetic risk frequency set of a vehicle, a storage medium, and a vehicle. The vehicle includes a target component, and the probability that the target component generates electromagnetic noise is greater than the probability that any other component in the vehicle generates electromagnetic noise. The method may include: in response to a voltage drop of the target component to a preset voltage threshold, performing an impedance test on the target component to obtain an impedance test result, wherein the impedance test result indicates the risk level of the target component causing the vehicle's electromagnetic compatibility performance to fail; based on the impedance test result, determining the frequency information and amplitude information of the target component, wherein the amplitude information indicates the interference intensity of electromagnetic noise on electromagnetic compatibility performance; and based on the frequency information and amplitude information, determining the electromagnetic risk frequency set of the vehicle. This application solves the technical problem of low efficiency in determining the electromagnetic risk frequency set of a vehicle.

Description

Technical Field

[0001] This application relates to the field of electromagnetic compatibility technology in vehicles, and more specifically, to a method for determining the electromagnetic risk frequency set of a vehicle, a storage medium, and a vehicle. Background Technology

[0002] Currently, the development of electromagnetic compatibility (EMC) for vehicles heavily relies on vehicle-level radiated emissions and immunity measurements, which require expensive and time-consuming testing in anechoic chambers. When target components (high-voltage components) operate in a vehicle, they generate broadband interference. However, the aforementioned technologies cannot predict the interference risk frequencies of these target components during the design phase. Problems can only be identified passively after integration, relying on experience to disassemble and inspect each component. Therefore, the technical problem of inefficiently determining the electromagnetic risk frequency set of vehicles remains.

[0003] There is currently no effective solution to the aforementioned technical problems. Summary of the Invention

[0004] This application provides a method for determining the electromagnetic risk frequency set of a vehicle, a storage medium, and a vehicle, to at least solve the technical problem of low efficiency in determining the electromagnetic risk frequency set of a vehicle.

[0005] According to one aspect of the embodiments of this application, a method for determining the electromagnetic risk frequency set of a vehicle is provided. The vehicle includes a target component, and the probability that the target component generates electromagnetic noise is greater than the probability that other components in the vehicle, excluding the target component, generate electromagnetic noise. The method may include: responding to a voltage drop of the target component to a preset voltage threshold, performing an impedance test on the target component to obtain an impedance test result, wherein the impedance test result is used to indicate the risk level of the target component causing the vehicle's electromagnetic compatibility performance to enter a failure state; based on the impedance test result, determining the frequency information and amplitude information of the target component, wherein the frequency information is the resonant frequency of the electromagnetic noise generated by the target component that causes the electromagnetic compatibility performance to enter a failure state, and the amplitude information is used to indicate the interference intensity of the electromagnetic noise on the electromagnetic compatibility performance; based on the frequency information and amplitude information, determining the electromagnetic risk frequency set of the vehicle, wherein the electromagnetic risk frequency set is the set of resonant frequencies that cause the electromagnetic compatibility performance to switch from a normal state to a failure state.

[0006] Optionally, the method further includes: performing a power-down operation on the vehicle in response to a determination command of the electromagnetic risk frequency set; controlling the target component to perform a discharge operation after the vehicle has completed the power-down operation; and acquiring the voltage of the target component after the discharge operation.

[0007] Optionally, acquiring the voltage of the target component after performing the discharge operation includes: in response to the target component completing the discharge operation, performing a disconnection operation on the high-voltage interlock in the vehicle and a disconnection operation on the high-voltage power harness of the target component; and in response to the completion of the disconnection operation on the high-voltage interlock and the high-voltage power harness, detecting the voltage from the power port of the target component.

[0008] Optionally, the method further includes: connecting the target component to a vector network analyzer via an RF coaxial cable; calibrating the RF coaxial cable and the vector network analyzer to obtain a calibrated RF coaxial cable and a calibrated vector network analyzer.

[0009] Optionally, in response to the voltage of the target component decreasing to a preset voltage threshold, an impedance test is performed on the target component to obtain the impedance test result of the target component, including: setting the test parameters of the calibrated vector network analyzer; and controlling the calibrated vector network analyzer to perform an impedance test on the target component according to the test parameters to obtain the impedance test result.

[0010] Optionally, the impedance test result is an impedance curve, which is used to represent the impedance amplitude and phase change at different frequencies. Based on the impedance test result, the frequency information and amplitude information of the target component are determined, including: extracting frequency information from the impedance curve; and determining amplitude information based on the frequency information.

[0011] Optionally, determining amplitude information based on frequency information includes: determining the amplitude corresponding to the frequency information as the average value of the amplitudes corresponding to frequencies adjacent to the frequency information.

[0012] Optionally, based on frequency and amplitude information, the electromagnetic risk frequency set of the vehicle is determined, including: constructing a distribution map and a distribution matrix of the vehicle based on frequency and amplitude information, wherein the distribution map is used to represent the frequency points of different frequency information and the corresponding electromagnetic interference risk intensity, and the distribution matrix represents the correspondence between the interference risk amplitude of the target component at different frequency points; and determining the electromagnetic risk frequency set based on the distribution map and the distribution matrix.

[0013] According to another aspect of the embodiments of this application, an apparatus for determining the electromagnetic risk frequency set of a vehicle is also provided. The apparatus may include: a testing unit, configured to perform an impedance test on the target component in response to a voltage drop to a preset voltage threshold, and obtain an impedance test result for the target component, wherein the impedance test result is used to indicate the degree of risk of the target component causing the vehicle's electromagnetic compatibility performance to enter a failure state; a first determining unit, configured to determine the frequency information and amplitude information of the target component based on the impedance test result, wherein the frequency information is the resonant frequency of the electromagnetic noise generated by the target component that causes the electromagnetic compatibility performance to enter a failure state, and the amplitude information is used to indicate the interference intensity of the electromagnetic noise on the electromagnetic compatibility performance; and a second determining unit, configured to determine the electromagnetic risk frequency set of the vehicle based on the frequency information and the amplitude information, wherein the electromagnetic risk frequency set is the set of resonant frequencies that cause the electromagnetic compatibility performance to switch from a normal state to a failure state.

[0014] According to another aspect of the embodiments of this application, a computer-readable storage medium is also provided. The computer-readable storage medium includes a stored program, wherein, when the program is executed, it controls the device where the computer-readable storage medium is located to perform the methods described in the embodiments of this application.

[0015] According to another aspect of the embodiments of this application, a processor is also provided. This processor is used to run a program, wherein the program executes the methods described in the embodiments of this application during runtime.

[0016] According to another aspect of the embodiments of this application, an electronic device is also provided. The electronic device includes a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to perform the methods described in the embodiments of this application.

[0017] According to another aspect of the embodiments of this application, a computer program product is also provided. This computer program product includes a computer program that, when executed by a processor, implements the methods described in the embodiments of this application.

[0018] According to another aspect of the embodiments of this application, a vehicle is also provided. The vehicle includes a memory and a processor, the memory storing a computer program, and the processor being configured to run the computer program to perform the methods described in the embodiments of this application.

[0019] In this embodiment, if it is necessary to determine the electromagnetic risk frequency set of a vehicle, and if the voltage of each target component in the vehicle drops to a preset voltage threshold, impedance testing can be performed on each target component to obtain the impedance test results. Based on the impedance test results, the frequency and amplitude information of each target component can be determined. Thus, by combining the frequency and amplitude information of each target component, the electromagnetic risk frequency set of the entire vehicle can be determined. In other words, in this embodiment, after the voltage of the target components in the vehicle drops to a preset voltage threshold, impedance testing is performed on each target component to obtain its frequency and amplitude information. Through this frequency and amplitude information, the potential risk frequencies that could cause EMC failures in the target components are directly correlated. Based on the frequency and amplitude information of multiple target components, an electromagnetic risk frequency set is constructed, enabling a systematic and quantitative prediction of risk frequencies. The method described in this application embodiment does not require the entire vehicle to be powered on or to enter an anechoic chamber, overcoming the lag of relying on vehicle host testing and experience-based troubleshooting in related technologies. It advances EMC risk identification from "post-event rectification" to the "design prediction" stage, significantly improving the efficiency of determining the electromagnetic risk frequency set. It fundamentally solves the problems of lagging and low efficiency in frequency set determination in the prior art, and solves the technical problem of low efficiency in determining the electromagnetic risk frequency set of vehicles, thus achieving the technical effect of improving the efficiency of determining the electromagnetic risk frequency set of vehicles. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0021] Figure 1 This is a flowchart of a method for determining the electromagnetic risk frequency set of a vehicle according to an embodiment of this application;

[0022] Figure 2 This is a flowchart of a method for predicting the electromagnetic interference risk frequency of an electric vehicle according to an embodiment of this application;

[0023] Figure 3 This is a schematic diagram of an electric vehicle impedance test setup according to an embodiment of this application;

[0024] Figure 4 This is a schematic diagram of a low-impedance high-voltage modular plug according to an embodiment of this application;

[0025] Figure 5 This is a schematic diagram of the electromagnetic interference risk frequency-amplitude of an electric vehicle according to an embodiment of this application;

[0026] Figure 6This is a schematic diagram of a device for determining the electromagnetic risk frequency set of a vehicle according to an embodiment of this application. Detailed Implementation

[0027] 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 with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present application.

[0028] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0029] According to an embodiment of this application, an embodiment of a method for determining the electromagnetic risk frequency set of a vehicle is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0030] Figure 1 This is a flowchart of a method for determining the electromagnetic risk frequency set of a vehicle according to an embodiment of this application, as shown below. Figure 1 As shown, the vehicle includes a target component, and the probability that the target component generates electromagnetic noise is greater than the probability that other components in the vehicle, excluding the target component, generate electromagnetic noise. The method may include the following steps:

[0031] In step S102, in response to the voltage of the target component decreasing to a preset voltage threshold, an impedance test is performed on the target component to obtain the impedance test result of the target component.

[0032] In the technical solution provided by step S102 of this application, the impedance test results can be used to indicate the risk level of the target component causing the electromagnetic compatibility performance of the vehicle to enter a failure state.

[0033] Optionally, the target component can refer to a high-voltage component in the vehicle that is prone to generating significant electromagnetic noise. This target component exhibits a much higher electromagnetic emission intensity than other low-voltage components during operation, making it a major source of EMC problems. In other words, the target component can be the core object for identifying the overall vehicle EMC risk. For example, the target component can be the vehicle's electric drive system, battery pack, DC-DC converter (DCDC), on-board charger (OBC), positive temperature coefficient heater (PTC), compressor, etc. No specific limitations are imposed here; any component that affects the EMC of the vehicle is within the protection scope of this application's embodiments.

[0034] Optionally, the preset voltage threshold can be a voltage critical value set to ensure the safety of impedance testing of the target component. For example, the preset voltage threshold is 0V, which is used to confirm that the high-voltage component has been completely de-energized and the capacitor has been discharged, to prevent electric shock or equipment damage during impedance testing, and is a prerequisite for starting a safe test.

[0035] Optionally, the impedance test results can refer to the curves (impedance curves / impedance amplitude curves) of the impedance amplitude and phase of the target component in a specific frequency band (e.g., 150kHz–30MHz) obtained by a vector network analyzer. The impedance test results can be used to reflect the impedance characteristics of the target component at the resonant point and to quantify the potential risk of the target component inducing EMC failure, such as key parameters like the number of resonant frequencies and peak amplitude.

[0036] Optionally, the aforementioned electromagnetic compatibility (EMC) performance can refer to the ability of the vehicle's electronic and electrical systems to operate normally in an electromagnetic environment without causing unacceptable interference to other components. EMC failure can manifest as excessive radiated emissions or insufficient immunity; impedance test results can indirectly reflect whether the target component is prone to triggering this failure at a specific frequency.

[0037] In this embodiment, if it is necessary to determine the electromagnetic risk frequency set of the vehicle, the voltage of the target component can be reduced. If the voltage of the target component is reduced to a preset voltage threshold, the impedance of the target component can be tested to obtain the impedance test result of the target component.

[0038] Optionally, if it is necessary to determine the risk frequency set of the vehicle, a high-voltage power-off operation can be performed on the vehicle to cut off the power supply to the high-voltage circuit of the entire vehicle, ensuring that the target components stop working. Subsequently, wait at least 30 minutes to allow the high-voltage capacitors to reduce the residual voltage to a safe level through natural discharge or passive discharge circuits.

[0039] Optionally, during the above steps, a high-precision multimeter can be used to sequentially test the voltage at the positive and negative ports of the target component until the voltage at all measurement points is stably lower than the preset voltage threshold, ensuring that no residual charge causes testing risks. After confirming that the voltage has dropped to the preset voltage threshold, the high-voltage interlock circuit can be disconnected to physically isolate the target component from the vehicle's high-voltage wiring harness, avoiding interference from parallel circuits on the test results. The impedance testing system is then connected to the high-voltage port of the target component. This impedance testing system may include a vector network analyzer, a double-shielded coaxial cable, an N-type RF adapter, a low-impedance high-voltage modular plug, and a grounding wire. The two ends of the modular plug are connected to the positive and negative terminals respectively and short-circuited via a common copper busbar to ensure extremely low contact impedance. The grounding wire is reliably connected to the vehicle chassis grounding point.

[0040] Step S104: Based on the impedance test results, determine the frequency information and amplitude information of the target component.

[0041] In the technical solution provided in step S104 of this application, the frequency information is the resonant frequency of the electromagnetic noise generated by the target component, which causes the electromagnetic compatibility performance to enter a failure state. The amplitude information is used to represent the interference intensity of the electromagnetic noise on the electromagnetic compatibility performance.

[0042] Optionally, the aforementioned frequency information may refer to the resonant frequency point exhibited by the target component in the impedance test curve. This resonant frequency point corresponds to the extreme impedance value generated by the inductor and capacitor (LC) resonant circuit formed by the equivalent inductance and capacitance within the target component at a specific frequency band. It is the inherent characteristic frequency point where the component is most likely to radiate or couple electromagnetic energy in a passive state, directly reflecting the interference frequency band that may trigger EMC exceedances (such as excessive radiated emissions) in the entire vehicle. The aforementioned amplitude information may refer to the average impedance amplitude within the aforementioned resonant frequency point and adjacent frequency bands (such as two frequencies before and after it). This is used to quantify the disturbance intensity of the target component to the external electromagnetic environment at a specific frequency. A higher amplitude indicates a more significant impedance change at that frequency point, a stronger electromagnetic energy release capability, and a greater potential for interference to surrounding components.

[0043] In this embodiment, after performing an impedance test on the target component and obtaining the impedance test results, the frequency information and amplitude information of the target component can be determined based on the impedance test results.

[0044] Optionally, after completing the impedance test of the target component and obtaining its impedance amplitude curve across the entire frequency band, the peak detection of the impedance curve can be performed manually or with software assistance to identify local maxima points where the impedance amplitude is significantly higher than that of neighboring frequencies. These local maxima points correspond to the natural resonance of the resonant circuit formed by the parasitic inductance and capacitance inside the target component at a specific frequency, which is the frequency information. This represents the key frequency point at which the target component is most likely to generate electromagnetic noise and cause the electromagnetic compatibility performance of the entire vehicle to fail. Each target component may have one to three such resonant frequencies. Some components without obvious structural resonance may not have any effective frequency points.

[0045] Optionally, after determining the frequency information, for each identified resonant frequency point, five consecutive frequency points are selected, including the resonant frequency point and the two frequency points to its left and right. The corresponding impedance amplitude is read, and the average value of these five resonant frequency points is calculated as the amplitude information corresponding to the resonant frequency. The amplitude information quantifies the strength of the electromagnetic energy released by the component at the resonant frequency point; the higher the amplitude, the greater the potential for interference to surrounding electronic systems by the target component in that frequency band.

[0046] In this embodiment, the original continuous impedance curve is transformed into a set of discrete "frequency-amplitude" feature pairs with clear physical meaning using the above method. This lays a precise and comparable data foundation for the subsequent aggregation and visualization analysis of interference risks across multiple vehicle components. This step achieves efficient extraction of electromagnetic risk characteristics from raw measurement data, allowing for the early identification of high-risk frequencies without relying on whole-vehicle EMC anechoic chamber testing, significantly reducing the uncertainty and cost of later-stage remediation.

[0047] Step S106: Based on frequency and amplitude information, determine the electromagnetic risk frequency set of the vehicle.

[0048] In the technical solution of step S106 of this application, the electromagnetic risk frequency set is the set of resonant frequencies that cause electromagnetic compatibility performance to switch from a normal state to a failure state.

[0049] Optionally, the electromagnetic risk frequency set can refer to a comprehensive frequency domain risk list formed by summarizing the resonant frequencies and corresponding amplitude information of each target component identified based on the impedance testing of the high-voltage components of the entire vehicle. This electromagnetic risk frequency set is not an independent feature of a single target component, but rather a global electromagnetic interference risk spectrum set composed of the interference frequency points of various high-voltage components in the vehicle, such as the electric drive, battery pack, DC-DC converter, and OBC, which are uniformly superimposed and integrated. This electromagnetic risk frequency set can be used to reflect all potential resonant frequencies that may cause the electromagnetic compatibility performance of the entire vehicle to abruptly change from a normal state to a failure state under static conditions. Each frequency point in this electromagnetic risk frequency set is not only marked with its existence but also associated with the corresponding interference intensity (i.e., amplitude information), thus forming a frequency domain risk map with weights and priorities. For example, the electromagnetic risk frequency set can be a distribution map of electromagnetic interference risk frequencies for the entire vehicle.

[0050] In this embodiment, after determining the frequency and amplitude information based on the impedance test results, the electromagnetic risk frequency set of the vehicle can be determined based on the aforementioned frequency and amplitude information.

[0051] Optionally, after acquiring the frequency and amplitude information of each high-voltage component, the resonant frequency points of all components are uniformly aggregated to form an initial candidate frequency list. Subsequently, for each frequency point in the initial candidate frequency list, it is determined whether the frequency point is reproduced by multiple target components. If a frequency point appears in multiple components, the interference risk of that frequency point is amplified, and the threat weight of the frequency point at the vehicle level is increased accordingly. At the same time, for each unique frequency point, the amplitude information of the corresponding target components is recorded, and the highest amplitude value or weighted average value is used as the vehicle-wide representative amplitude of that frequency point to reflect the contribution of the most serious interference source.

[0052] Optionally, based on this, low-risk frequency points with amplitudes below a preset threshold are eliminated, while high-frequency, high-amplitude resonant points with engineering significance are retained, ultimately forming a concise, effective, and engineering-applicable set of electromagnetic risk frequencies.

[0053] In this embodiment, the aforementioned electromagnetic risk frequency set, with frequency as the axis and amplitude as the weight, comprehensively depicts the distribution of interference frequency bands most likely to cause electromagnetic compatibility performance failure in a static state for the entire vehicle. This method achieves intelligent aggregation from local features of a single component to global risks across the entire vehicle, breaking through the inefficient traditional model of relying on item-by-item inspection through whole-vehicle testing. It enables engineers to clearly identify high-risk frequency points and their sources during the design phase, allowing for early structural or circuit optimization, significantly shortening the development cycle, reducing testing rework costs, and improving the foresight and controllability of EMC design.

[0054] In steps S102 to S106 of this application, if it is necessary to determine the electromagnetic risk frequency set of the vehicle, and if the voltage of each target component in the vehicle drops to a preset voltage threshold, impedance testing can be performed on each target component to obtain the impedance test results. Based on the impedance test results, the frequency and amplitude information of each target component can be determined. Thus, by combining the frequency and amplitude information of each target component, the electromagnetic risk frequency set of the entire vehicle can be determined. In other words, in this embodiment, after the voltage of the target components in the vehicle drops to a preset voltage threshold, impedance testing is performed on each target component to obtain its frequency and amplitude information. Through this frequency and amplitude information, the potential risk frequencies that could cause EMC failures in the target components are directly correlated. Based on the frequency and amplitude information of multiple target components, an electromagnetic risk frequency set is constructed, enabling a systematic and quantitative prediction of risk frequencies. The method described in this application embodiment does not require the entire vehicle to be powered on or to enter an anechoic chamber, overcoming the lag of relying on vehicle host testing and experience-based troubleshooting in related technologies. It advances EMC risk identification from "post-event rectification" to the "design prediction" stage, significantly improving the efficiency of determining the electromagnetic risk frequency set. It fundamentally solves the problems of lagging and low efficiency in frequency set determination in the prior art, and solves the technical problem of low efficiency in determining the electromagnetic risk frequency set of vehicles, thus achieving the technical effect of improving the efficiency of determining the electromagnetic risk frequency set of vehicles.

[0055] The method described in this embodiment will be further described below.

[0056] As an optional embodiment, the method further includes: performing a power-down operation on the vehicle in response to a determination command of the electromagnetic risk frequency set; controlling the target component to perform a discharge operation after the vehicle has completed the power-down operation; and acquiring the voltage of the target component after the discharge operation.

[0057] In this embodiment, if a determination command targeting a set of electromagnetic risk frequencies is detected, a power-down operation can be performed on the vehicle. After the vehicle completes the power-down operation, a discharge operation can be performed on the target component, and the voltage of the target component after the discharge operation can be acquired. The determination command can refer to a start signal initiated by the operator or control system to trigger the impedance testing process for the high-voltage components of the entire vehicle. This determination command can be issued after the vehicle has been prepared for static loading and confirmation of no high-voltage operation.

[0058] Optionally, the aforementioned power-down operation can refer to the process of completely disconnecting the vehicle's high-voltage power supply system. Specifically, this involves disconnecting the main positive and main negative contactors of the high-voltage power battery, ensuring that no current flows through the vehicle's high-voltage busbar, and guaranteeing that all high-voltage components are in a static state without external power input. This power-down operation is a prerequisite for conducting safety impedance testing, aiming to eliminate interference from external power supply on the measurement results and ensure the electrical safety of personnel and equipment during subsequent operations.

[0059] Optionally, the above-mentioned discharge operation may refer to, after the vehicle has completed the power-off operation, guiding the residual capacitors inside the high-voltage components (such as the bus capacitors of the electric drive inverter, the DC-DC input and output capacitors, the OBC filter capacitors, etc.) to release the stored charge through active or passive means, so that the voltage of the target component can be reduced to below a preset voltage threshold.

[0060] Optionally, upon receiving a determination command for the electromagnetic risk frequency set, the vehicle's high-voltage system safety response procedure is triggered. This command is manually triggered by the operator after confirming that the vehicle is stationary and not in operation, or automatically issued by the development and testing software based on preset conditions, marking the formal initiation of the vehicle's electromagnetic interference risk assessment process. After responding to the aforementioned determination command, the vehicle's high-voltage main circuit is disconnected, and a power-down operation is performed. The Battery Management System (BMS) issues a command to disconnect the high-voltage contactor, severing the electrical connection between the power battery and all high-voltage components, ensuring that the vehicle's high-voltage bus is completely disconnected from the energy supply and enters a passive state.

[0061] Optionally, after the power-down operation is completed, a safety waiting phase is initiated, and the discharge control program of the target component is activated. Discharge enable signals are sequentially sent to high-voltage components such as the electric drive, DC-DC converter, OBC, and PTC to activate the built-in discharge circuits of each high-voltage component, or by connecting a pre-set discharge resistor through an external discharge circuit, forcibly guiding the rapid release of residual charge in the large-capacity capacitors inside the components. During the discharge process, a high-precision voltage acquisition module can monitor the voltage changes at the positive and negative high-voltage ports of each target component in real time, continuously collecting voltage data until the terminal voltages of all components are stably lower than the safety threshold (preset voltage threshold), meeting electrical work safety standards.

[0062] Optionally, once the voltage of all target components has been detected to have dropped to a safe range and remained stable for more than a preset time (e.g., 30 seconds), the discharge operation is confirmed to be complete. At this time, the voltage status signal is fed back to the main control unit as a verification basis for the safety of subsequent impedance test connections, ensuring that the connection operation of the test probe will not cause the risk of electric shock or arcing.

[0063] In the embodiments of this application, the above method realizes closed-loop management of the entire process from risk analysis initiation to electrical safety confirmation through standardized instruction drive and sequence control, effectively eliminating the risk of personal injury and equipment damage caused by residual pressure, providing a basic guarantee for subsequent high-precision impedance measurement, and significantly improving the safety and repeatability of the whole method in engineering field applications.

[0064] As an optional embodiment, obtaining the voltage of the target component after performing a discharge operation includes: in response to the target component completing the discharge operation, performing a disconnection operation on the high-voltage interlock in the vehicle and a disconnection operation on the high-voltage power harness of the target component; and in response to the completion of the disconnection operation on the high-voltage interlock and the high-voltage power harness, detecting the voltage from the power port of the target component.

[0065] In this embodiment, during the process of acquiring the voltage of the target component after the discharge operation, if it is detected that the target component has completed the discharge operation, the high-voltage interlock in the vehicle can be disconnected, and the high-voltage power harness in the target component can also be disconnected. After both the high-voltage interlock and the high-voltage power harness have been disconnected, the voltage can be detected from the power port of the target component. The high-voltage interlock can be a closed-loop detection circuit used to ensure the safety of the electric vehicle's high-voltage system. Its core function is to monitor the connection integrity between high-voltage components in real time through a physically connected signal circuit. The high-voltage power harness can refer to a dedicated cable system connecting the power battery and each high-voltage component, typically consisting of double-insulated shielded cables, high-voltage connectors, and protective sleeves, used to transmit DC high-voltage electricity (e.g., 300V–800V). The power port can refer to the physical electrical interface on the high-voltage component used to connect the high-voltage power harness, and can include two terminals: a positive (+) terminal and a negative (-) terminal. The power port is directly connected to the bus capacitor, power switching device, or filter circuit of the target component.

[0066] Optionally, in response to the target component completing its discharge operation and triggering the high-voltage interlock disconnect command, after confirming that the port voltage of each target component has stabilized below the safety threshold for a duration exceeding a preset delay (e.g., 30 seconds), the control system automatically issues the high-voltage interlock disconnect command. This high-voltage interlock disconnect command can be sent to the high-voltage interlock circuit controller to forcibly disconnect the closed-loop structure of the interlock detection circuit, causing the entire vehicle to enter an interlock failure state. This operation prevents subsequent operations from triggering a BMS system recovery error due to abnormalities such as loose connectors, thereby avoiding the risk of accidental power-on.

[0067] Optionally, in response to a successful high-voltage interlock disconnection, during the physical disconnection of the high-voltage power harness, after the high-voltage interlock circuit confirms the disconnection, the operator or automatic control device (such as an electric plug-in mechanism) is prompted to physically disconnect the high-voltage power harness of the target component from its power port. This operation includes disconnecting the high-voltage connectors at both the positive and negative terminals, ensuring that there is no electrical coupling path between the target component and the power battery or high-voltage bus. This step is crucial for achieving complete isolation, preventing interference to subsequent voltage measurements due to residual charge, parasitic capacitance, or grounding loops in the cables.

[0068] Optionally, in response to the complete disconnection of both the high-voltage interlock and the high-voltage power supply harness, during the process of initiating power port voltage detection, after confirming that the high-voltage interlock has been disconnected and the high-voltage harness has been physically separated, a high-precision, high-input-impedance voltage acquisition device (such as a digital multimeter or an isolated voltage probe) is activated and directly connected to the power port (between the positive and negative terminals) of the target component. At this time, because the external power supply and the interlock circuit are isolated, the measured voltage is the only residual voltage of the internal energy storage element (such as the bus capacitor) of the component, and the measurement result truly reflects the degree of discharge completion without external signal interference.

[0069] Optionally, use a multimeter to check whether the voltage at the power supply ports of all high-voltage components has dropped to 0V.

[0070] In this embodiment, the method described above establishes a complete, verifiable, and engineering-applicable high-voltage safety isolation mechanism through a four-step progressive safety verification process: "discharge completion → interlock disconnection → harness separation → port detection." This process not only ensures the absolute personal safety of measurement personnel when contacting high-voltage ports but also eliminates potential interference from external power supply paths and interlock feedback loops to voltage measurements at the electrical source, significantly improving the accuracy and reliability of voltage detection data.

[0071] As an optional embodiment, the method further includes: connecting the target component to a vector network analyzer via an RF coaxial cable; calibrating the RF coaxial cable and the vector network analyzer to obtain a calibrated RF coaxial cable and a calibrated vector network analyzer.

[0072] In this embodiment, the target component and the vector network analyzer can be connected via an RF coaxial cable. The RF coaxial cable and the vector network analyzer can be calibrated to obtain a calibrated RF coaxial cable and a calibrated vector network analyzer. The aforementioned RF coaxial cable can be a dedicated cable for transmitting radio frequency (RF) signals, consisting of a four-layer structure: a center conductor, an insulating medium, a shielding layer, and an outer sheath, possessing good electromagnetic shielding characteristics and a stable characteristic impedance (e.g., 50Ω). The aforementioned vector network analyzer can be used to inject a frequency sweep excitation signal (e.g., 150kHz–30MHz) into the target high-voltage component and receive reflected and transmitted signals, generating the impedance curve of the target component through an internal algorithm.

[0073] Optionally, after discharging and electrically isolating the target component, the operator connects one end of the RF coaxial cable to the measurement port of the Vector Network Analyzer (VNA) via an N-type or SMA-type RF adapter; the other end is electrically connected to the high-voltage power port (positive and negative) of the target component via a low-impedance high-voltage connector. The above connection must ensure the following conditions: the cable shielding layer reliably contacts the vehicle grounding point to form a good grounding loop; the center conductor is firmly in contact with the copper common conductive terminal of the connector to avoid measurement deviations caused by contact resistance; all connection points are free from looseness, oxidation, or contamination to ensure the continuity and stability of RF signal transmission.

[0074] Optionally, power on the vector network analyzer and enter calibration mode. It will automatically identify the currently connected port type, cable length, and connector specifications. If an anomaly is detected (such as an open circuit, short circuit, or impedance mismatch), the instrument will prompt you to check the physical connections. After confirmation, proceed to the next calibration preparation step. Use standard calibration kits (Open, Short, Load, Through) to compensate for systematic errors throughout the measurement link: Open circuit calibration involves leaving the test port floating and measuring the total internal reflection signal to obtain a reflection coefficient reference; Short circuit calibration involves shorting the test port to ground to obtain an ideal short-circuit response; Load calibration involves connecting a 50 Ω precision load to obtain transmission and reflection references under matched conditions; Optional through calibration is used if dual-port measurements are employed or if adapter effects need to be compensated, through-reflect-line calibration (TRL) is performed. After calibration, the VNA generates a "calibration factor" database to correct systematic errors introduced by cable loss, connector reflection, drift, etc., in subsequent measurements in real time, ensuring that the impedance measurement results represent the true impedance response of the target component.

[0075] Optionally, after successful calibration, the VNA automatically saves the current calibration data to the current configuration file and displays a "Calibration Complete" or similar status message on the interface. At this point, the RF coaxial cable and the vector network analyzer together constitute a "calibrated measurement system," and its measurement accuracy reaches the instrument's nominal level (e.g., ±0.1 dB amplitude, ±1° phase) before proceeding to the subsequent impedance sweep frequency test stage. Measurements must not be started if calibration is incomplete or has failed to ensure data reliability.

[0076] In this embodiment, the above method constructs a high-precision, traceable, and interference-resistant RF impedance measurement reference system through a four-step closed-loop operation: "physical connection → system initialization → standard calibration → status confirmation." This method effectively eliminates system errors commonly found in engineering practice, such as cable loss, connector reflection, and poor grounding, ensuring that the obtained impedance curve of the high-voltage component truly reflects its inherent electromagnetic characteristics, rather than the distorted response of the testing device. This method significantly improves the accuracy and repeatability of resonant frequency identification.

[0077] As an optional embodiment, step S102, in response to the voltage of the target component decreasing to a preset voltage threshold, performs an impedance test on the target component to obtain the impedance test result of the target component, including: setting the test parameters of the calibrated vector network analyzer; controlling the calibrated vector network analyzer according to the test parameters to perform an impedance test on the target component to obtain the impedance test result.

[0078] In this embodiment, during the impedance testing of the target component and obtaining the impedance test results, the test parameters of the calibrated vector network analyzer can be set. According to the test parameters, the calibrated vector analyzer is controlled to perform impedance testing on the target component and obtain the impedance test results. The aforementioned test parameters may include impedance test frequency, number of scan points, number of scans, scan bandwidth, and interface display parameters. The impedance test frequency (e.g., 150kHz–30MHz) defines the frequency range covered by the VNA during impedance sweep frequency measurement. The number of scan points refers to the total number of discrete frequency sampling points acquired by the VNA within the set frequency range. For example, setting 1001 scan points means uniformly distributing 1001 test frequency points within the 150kHz to 30MHz range. More points result in higher frequency resolution and more accurate identification of narrowband resonant peaks; however, too many points can prolong the test time. The number of scans refers to the number of times the VNA repeatedly measures the same frequency point and averages the results. For example, setting the number of scans to 4 means that each frequency point is measured 4 times and the arithmetic mean is output. The aforementioned number of scans can be used to suppress the influence of random noise (such as environmental electromagnetic interference and internal instrument thermal noise) on the measurement results, improving the signal-to-noise ratio and stability of the impedance curve, especially suitable for impedance measurement of high-voltage components with low signal levels. The aforementioned scan bandwidth can be the 3dB passband width of the intermediate frequency filter in the VNA receiver, used to control the frequency resolution and noise level of the measurement system. The aforementioned interface display parameters control the visualization format and range of the impedance curve on the VNA screen, and can include display type, amplitude range, frequency readability, and marking functions.

[0079] Optionally, before performing impedance testing on the target high-voltage component (such as the electric drive controller, OBC, DC-DC converter, etc.), the system or operator continuously monitors the residual voltage at its high-voltage power supply port. This monitoring is achieved using a high-precision multimeter or an embedded voltage acquisition module, with a sampling frequency of no less than 1Hz. When the voltage across the target component is continuously and stably lower than a preset voltage threshold, it is determined that the high-voltage capacitor has been fully discharged, meeting the electrical safety operating conditions, and triggering the subsequent impedance testing process.

[0080] Optionally, in response to a voltage threshold compliance signal, the control system automatically loads or prompts the operator to confirm the preset VNA test parameters. After confirming that the calibration status is valid (displaying "Calibration Complete") and there are no connection abnormality alarms, the control system sends control commands to drive the calibrated VNA to perform single-port impedance sweep frequency measurement according to the preset parameters. The VNA sequentially outputs excitation signals, acquires the reflection coefficient Γ of the target component port, and calculates and records the complex impedance value at each frequency point in real time.

[0081] In this embodiment, a closed-loop process—voltage safety threshold triggering → intelligent parameter loading → automated frequency sweep measurement → data integrity verification → structured output—achieves highly safe, accurate, and reproducible automated acquisition of the impedance characteristics of high-voltage components in electric vehicles. This method eliminates the risk of inconsistencies caused by manual intervention, ensures strictly controlled measurement conditions, and significantly improves data reliability. Furthermore, by precisely matching EMC frequency bands and optimizing parameters, impedance test results directly serve the prediction of vehicle EMC risks, greatly shortening the development cycle and reducing reliance on anechoic chamber testing.

[0082] As an optional embodiment, the impedance test result is an impedance curve, which is used to represent the impedance amplitude and phase change state at different frequencies. Step S104, based on the impedance test result, determines the frequency information and amplitude information of the target component, including: extracting frequency information from the impedance curve; and determining amplitude information based on the frequency information.

[0083] In this embodiment, during the process of determining the frequency and amplitude information of the target component based on impedance test results, frequency information can be extracted from the impedance curve. Amplitude information is then determined based on the frequency information. The impedance curve can be a graphical representation of the impedance characteristics of the target component in the frequency domain as a function of the excitation frequency. The impedance curve can be presented in a dual Y-axis or split-plot format with frequency as the horizontal axis and impedance amplitude and phase as the vertical axis, fully depicting the impedance characteristics of the target component to AC signals over a wide frequency range.

[0084] Optionally, after completing the swept-frequency impedance test of the target high-voltage component, the vector network analyzer outputs a complete set of frequency-impedance response data. This data is recorded in discrete point form, with the complex impedance value corresponding to each frequency point being collected sequentially within the 150kHz to 30MHz frequency band according to a preset number of scan points (e.g., 1001 points). The impedance amplitude and phase at each frequency point are then calculated, forming a continuous impedance curve.

[0085] Optionally, automated peak detection is performed on the impedance curve to identify characteristic frequencies that may cause electromagnetic interference. This process first estimates the background baseline amplitude as a noise reference; then, all data points are scanned to find local maxima that meet the following conditions: the amplitude of the local maximum is at least 10 dB higher than the baseline, indicating that its energy significantly exceeds the ambient noise; the local maximum is a local highest point, meaning that the amplitudes of the points preceding and following it are both lower than the local maximum; the spacing between adjacent effective peaks is greater than twice the scan resolution to avoid duplicate counting due to data density; and the corresponding phase is close to ±90°, confirming that the resonance is reactive-dominated and not resistive. Each point that meets the above conditions is marked as a characteristic frequency point, constituting the frequency information set of the target component.

[0086] Optionally, for each identified characteristic frequency point, instead of directly using its peak amplitude as an indicator of interference intensity, a five-point moving average method is used for amplitude weighting: five consecutive frequency points are selected, centered at the given frequency point and consisting of two adjacent frequency points before and after it; the amplitudes corresponding to these five points are extracted; and the average value is calculated as the representative amplitude value of the characteristic frequency. This method effectively smooths out instantaneous fluctuations, instrument noise, or local anomalies caused by poor contact during measurement, making the amplitude value more accurately reflect the energy contribution of the frequency point across the entire frequency band, and avoiding misjudgments caused by occasional interference at a single sampling point.

[0087] Optionally, all extracted characteristic frequencies and their corresponding weighted amplitude values ​​are paired to form an ordered set of frequency-amplitude correlation data. Each pair of data represents a specific electromagnetic interference risk source frequency and its intensity level. The above data does not include the original curves, but only retains key feature points to facilitate subsequent merging and analysis with the results of other high-voltage components in the vehicle, used to construct a vehicle-level electromagnetic interference risk frequency distribution matrix. If no effective characteristic frequency is detected, it is marked as "no significant resonance," indicating that the component has no significant EMC risk within the test frequency band; if multiple frequency points are detected with excessively close spacing (e.g., less than 100kHz), the system issues a "frequency aliasing" warning, indicating that there may be a loose test connection or calibration failure; if any weighted amplitude value abnormally exceeds a reasonable range (e.g., less than 0.5Ω or greater than 500Ω), a "data anomaly" alarm is triggered, requiring retesting; all outputs are bound to metadata such as test time, ambient temperature, and equipment number to ensure process traceability and result reproducibility.

[0088] In this embodiment, by accurately identifying the resonant point and calculating the five-point weighted amplitude, the electromagnetic interference characteristics implicit in the original impedance curve are transformed into quantifiable, comparable, and reusable engineering parameters, completely eliminating the inefficient traditional mode that relies on manual graph reading and experience-based judgment. The core advantage lies in improving the stability of amplitude assessment through a noise-resistant weighting mechanism and ensuring the physical authenticity of frequency identification through phase-assisted criteria, ultimately achieving a technological leap from "passive testing and rectification" to "proactive risk prediction."

[0089] As an optional embodiment, determining amplitude information based on frequency information includes: determining the amplitude corresponding to the frequency information as the average value of the amplitudes corresponding to frequencies adjacent to the frequency information.

[0090] In this embodiment, during the process of determining amplitude information based on frequency information, the amplitude corresponding to the frequency information and the average value of the amplitudes corresponding to frequencies adjacent to the frequency information can be determined as amplitude information.

[0091] Optionally, in the preliminary steps of impedance curve analysis, several significant resonant frequency points of the target component within the 150kHz–30MHz frequency band have been identified using a peak detection algorithm. Each resonant frequency point indicates a significant abrupt change in impedance amplitude at that frequency, posing a potential electromagnetic interference risk. For each characteristic frequency, its preceding and subsequent adjacent frequency points are searched in the original impedance curve data. Since the data is sampled at equal intervals, the system uses indexing to locate and obtain the resonant frequency point f. i Five consecutive frequency points centered on the center: the first two neighboring points f i-2 f i-1 Center point f i The last two neighboring points f i+1 f i+2 The five points mentioned above constitute a local frequency domain window, used to characterize the energy coverage range of the resonance peak in actual measurements.

[0092] Optionally, the impedance amplitude corresponding to the above five frequency points can be read from the data sequence of the impedance curve: |Z(f i-2 )|、|Z(f i-1 )|、|Z(f i )|、|Z(f i+1 )|、|Z(f i+2 The above amplitude values ​​are all real numbers, with the unit being ohms (Ω), reflecting the ability to impede electromagnetic energy at each frequency point. Specifically, |Z(f i The value is the resonant peak, and the rest are transition band data.

[0093] Optionally, the five amplitude values ​​can be arithmetically averaged to obtain the final amplitude information.

[0094] In this embodiment, amplitude information is determined by averaging five neighboring points centered on the characteristic frequency, achieving a shift from single-point peak values ​​to regional response, significantly enhancing the stability and engineering reliability of interference intensity assessment. Compared to directly using peak amplitude, this method effectively suppresses misjudgments caused by inherent noise in the measurement system, probe contact fluctuations, or occasional environmental interference, making risk assessment more closely reflect the energy coupling behavior in actual electromagnetic environments. This technique requires no additional hardware costs; data quality can be improved solely through algorithm optimization.

[0095] As an optional embodiment, step S106, determining the electromagnetic risk frequency set of the vehicle based on frequency information and amplitude information, includes: constructing a vehicle distribution map and a vehicle distribution matrix based on frequency information and amplitude information, wherein the distribution map is used to represent the frequency points of different frequency information and the corresponding electromagnetic interference risk intensity, and the distribution matrix represents the correspondence between the interference risk amplitude of the target component at different frequency points; and determining the electromagnetic risk frequency set based on the distribution map and the distribution matrix.

[0096] In this embodiment, during the process of determining the electromagnetic risk frequency set, a distribution map and a distribution matrix of the vehicle can be constructed based on frequency and amplitude information. The electromagnetic risk frequency set can be determined based on the aforementioned distribution map and distribution matrix. The distribution map can be an electromagnetic interference risk frequency-amplitude distribution map, which can be a two-dimensional graphical representation with frequency as the horizontal axis and impedance amplitude as the vertical axis, used to visually present all identified characteristic frequency points and their corresponding interference risk intensities for multiple high-voltage components of the vehicle within the test frequency band. The distribution matrix can be an electromagnetic interference risk frequency distribution matrix, which can be a structured two-dimensional data table format used to accurately record the interference risk amplitude value of each target high-voltage component at each characteristic frequency point.

[0097] Optionally, after completing the impedance frequency sweep test of each high-voltage component, a set of "characteristic frequency-weighted amplitude" pairs has been independently extracted for each component. The characteristic frequency is the significant resonant point identified in the impedance curve, and the weighted amplitude is the average amplitude of that frequency point and its five neighboring points. This dataset provides each component with an independent set of risk frequency identifiers and their intensity quantification values. The characteristic frequencies extracted from all high-voltage components are globally merged, duplicates are removed, and they are arranged in ascending order of frequency to form a global characteristic frequency set. This set contains all potential interference frequency points that have appeared in the test frequency band for all components of the vehicle, forming a unified coordinate reference for subsequent distribution maps and distribution matrices, ensuring that data from different components can be aligned and superimposed. Using the normalized global frequency set as the horizontal axis and the corresponding maximum weighted amplitude as the vertical axis, the interference risk intensity of each frequency point is plotted in a two-dimensional coordinate system. For each frequency point, if multiple components resonate at that point, the highest amplitude value is marked at that frequency position, or the degree of risk superposition is expressed by point density and color intensity. This diagram does not show the specific components involved, but only illustrates "which frequencies are most likely to cause interference" across the entire vehicle, providing a clear visual representation. Electromagnetic risk heat map of the whole vehicle It is used to quickly identify high-risk frequency bands.

[0098] Optionally, a two-dimensional data structure, namely a distribution matrix, is established with "components as rows and frequencies as columns". Each row represents a high-voltage component, and each column corresponds to a frequency point in the global characteristic frequency set. The value of each element in the above distribution matrix is ​​the weighted amplitude value of the component at the corresponding frequency point. If the component has no significant response at that frequency point, the value is assigned to zero.

[0099] Optionally, frequency points with amplitudes higher than a preset threshold (e.g., 10Ω) are identified based on the distribution map and used as candidate high-risk frequencies; the distribution matrix is ​​called to check whether each candidate frequency point is excited by at least two or more components; only when a frequency point meets both the conditions of "significant amplitude" and "co-occurrence of multiple components" is it formally included in the final electromagnetic risk frequency set.

[0100] In this embodiment, a closed-loop mechanism—characteristic frequency normalization → distribution map visualization → distribution matrix structuring → multi-dimensional joint screening—achieves system-level, quantitative, and traceable identification of electromagnetic interference risks in electric vehicle high-voltage systems. Compared to traditional methods relying solely on single-component testing or manual experience, this solution quickly identifies high-risk frequency bands through distribution maps, accurately locates risk sources through distribution matrices, and then uses amplitude + co-occurrence dual-condition filtering to ensure that the output electromagnetic risk frequency set has high accuracy, strong representativeness, and engineering operability.

[0101] The technical solutions of the embodiments of this application will be illustrated below with reference to preferred embodiments.

[0102] Currently, in the development of electromagnetic compatibility (EMC) for electric vehicles, the industry mainly relies on whole-vehicle EMC testing for problem identification and rectification. If there are issues with radiated emissions or radiated immunity, troubleshooting can only be done based on experience, either for individual components or systems, and it's difficult to quickly pinpoint the interference source. This approach suffers from high testing costs, long cycles, and low efficiency. The main sources of EMC interference in electric vehicles include high-voltage components such as the electric drive system, battery pack, PTC, DC-DC converter, OBC, and compressor. If a method could be designed during the development and design phase to predict or identify the EMC risk frequencies of high-voltage components in electric vehicles in advance, it would reduce the cost of testing and troubleshooting whole-vehicle EMC problems, quickly pinpoint the EMC source, shorten the development cycle, and improve development efficiency.

[0103] To address the high costs, long cycles, and low efficiency of EMC testing and troubleshooting for electric vehicles, a method for predicting electromagnetic interference (EMI) risk frequencies in electric vehicles has been invented. This method identifies EMI risk frequencies in advance, improving the efficiency of EMI troubleshooting. The method performs impedance testing on high-voltage components under vehicle conditions, obtaining impedance curves for each component. Based on the multi-port impedance resonant frequencies, it derives an EMI risk frequency distribution map and matrix for the entire vehicle, identifying EMI risk frequencies in advance, reducing troubleshooting time, and improving efficiency. The impedance testing system includes a vector network analyzer, coaxial cables, RF adapters, low-impedance high-voltage modular connectors, and grounding wires, eliminating the need for testing in a vehicle EMC laboratory and significantly reducing development and testing costs. The EMI risk frequency distribution map for the entire electric vehicle is a collection of multi-port impedance resonant frequencies, reflecting the potential interference risk frequencies of each high-voltage component. It provides data reference for diagnosing EMI non-compliance issues, improving troubleshooting efficiency and reducing costs.

[0104] The embodiments of this application will be further described below.

[0105] Figure 2 This is a flowchart of a method for predicting the electromagnetic interference risk frequency of an electric vehicle according to an embodiment of this application, such as... Figure 2 As shown, the method may include the following steps.

[0106] Step S201: The vehicle is powered off with high voltage.

[0107] In this embodiment, before assessing the electromagnetic interference risk of the entire vehicle, it is essential to ensure that the vehicle's high-voltage system is completely de-energized. This step involves shutting down the vehicle's high-voltage main contactor and activating the battery management system's discharge command, allowing the high-voltage bus capacitor to release residual energy through a natural discharge process. This provides a basic electrical safety prerequisite for subsequent operations and prevents the risk of high-voltage electric shock.

[0108] Optionally, perform vehicle preparation. Remove the high-voltage power to the vehicle and wait approximately 30 minutes or longer to ensure sufficient discharge time for the high-voltage capacitors.

[0109] Step S202: High-voltage interlock disconnected.

[0110] In this embodiment, after the high-voltage power is disconnected, the high-voltage interlock circuit of the entire vehicle is further disconnected manually or via a control signal to physically release the interlock protection mechanism between the modules of the high-voltage system. This operation ensures that the system will not automatically power on due to the detection of abnormal connections when subsequently disconnecting wiring harnesses or connecting test equipment, and is a key isolation step to ensure the safety of test personnel and equipment. Disconnecting the high-voltage interlock ensures the safety of subsequent high-voltage component testing operations.

[0111] Step S203: Disconnect the high-voltage component wiring harness.

[0112] In this embodiment, the original high-voltage power supply harnesses of all high-voltage components, such as the electric drive, DC-DC converter, OBC, PTC, and compressor, are physically disconnected one by one, separating them from the vehicle's high-voltage bus. This operation puts each component in an "isolated test" state, avoiding impedance measurement distortion caused by parallel circuits or parasitic coupling, and ensuring that subsequent test results truly reflect the resonant characteristics of each individual component. The high-voltage power supply harnesses of all high-voltage components are disconnected.

[0113] Step S204: Detect the voltage at the power ports of all high-voltage components.

[0114] In this embodiment, a high-precision digital multimeter is used to measure the voltage at the positive and negative power ports of each component with disconnected high-voltage wiring harnesses to confirm that the port voltages have all decayed below the safety threshold, serving as a final safety verification step. This step verifies and checks the preceding power-off operation, ensuring no residual charge remains and preventing equipment damage or personal injury caused by capacitor discharge during testing. The multimeter is used to sequentially check whether the power port voltages of all high-voltage components have dropped to 0V, ensuring the safety of testing personnel and equipment.

[0115] Step S205, Vehicle impedance test setup.

[0116] In this embodiment, a vector network analyzer is connected to the power port of the high-voltage component under test via a coaxial cable, an RF adapter, and a low-impedance high-voltage connector. Simultaneously, a grounding wire is reliably connected to the vehicle chassis grounding point, constructing a four-port impedance measurement loop that conforms to RF testing specifications. This arrangement ensures that the test signal flows only through the target component, avoiding external interference coupling, and is the physical basis for obtaining a high-precision impedance curve.

[0117] Figure 3 This is a schematic diagram of an electric vehicle impedance testing setup according to an embodiment of this application, as shown below. Figure 3 As shown, according to the electric vehicle impedance test layout diagram, connect the vector network analyzer, high-quality coaxial cable, RF adapter, low-impedance high-voltage modular connector, connecting wires, grounding wire, vehicle grounding point, and the high-voltage power supply port of the high-voltage component under test (e.g., high-voltage components 1-6). Connect one end of the high-quality coaxial cable (double-shielded) to the vector network analyzer port, and the other end to the N-type RF connector. Two wires are soldered to the other end of the N-type RF connector; the core of the wire is the connecting wire, and the outer shell is connected to the grounding wire and then to the vehicle grounding point.

[0118] Figure 4 This is a schematic diagram of a low-impedance high-voltage modular plug according to an embodiment of this application, as shown below. Figure 4As shown, the low-impedance high-voltage plug is connected to the positive and negative terminals of the high-voltage power supply port. The other end of the plug is connected to the common copper conductive terminal, and the two plugs, positive and negative, are short-circuited through the common copper conductive terminal to ensure good contact performance.

[0119] Step S206, impedance test of high voltage component 1.

[0120] In this embodiment, a vector network analyzer is started for the first high-voltage component under test (such as the electric drive unit), the scanning frequency band is set to 150kHz to 30MHz, and appropriate scan points, bandwidth, and averaging times are configured. Parametric frequency sweep measurement is performed to obtain the complex impedance response curve of the component in this frequency band. This process acquires its intrinsic electromagnetic characteristics in a static, non-excited, and non-operating manner, independent of the overall vehicle operating status.

[0121] Optionally, the vector network analyzer and high-quality coaxial cable need to be calibrated before testing. Then, the vector network analyzer parameters are set, including the impedance test frequency (e.g., 150kHz-30MHz), number of scan points, number of scans, scan bandwidth, and interface display. Impedance testing is performed using the vector network analyzer to obtain the impedance curve of high-voltage component 1, and the impedance resonant frequencies f11, f12, and f13 and their amplitude values ​​are extracted (the number of resonant frequencies is generally 1 to 3, but may also be 0).

[0122] Step S207: Extract the impedance resonant frequency of high-voltage component 1.

[0123] In this embodiment, the acquired impedance amplitude curve is subjected to automated peak detection. Combined with the phase change trend, the resonant frequency point that meets the physical conditions of significant energy, local maximum, and reactance dominance is identified as the characteristic interference frequency of the component.

[0124] Step S208: Perform impedance testing and resonant frequency extraction for other high-voltage components.

[0125] In this embodiment, steps S205 to S207 are repeated to perform the same impedance test and resonant frequency extraction process on all remaining high-voltage components (such as OBC, DC-DC, PTC, etc.) in sequence, forming an independent resonant frequency and weighted amplitude dataset for each component.

[0126] Step S209, Frequency distribution diagram of electromagnetic interference risk for the whole vehicle.

[0127] In this embodiment, the characteristic frequencies and weighted amplitude values ​​of all high-voltage components are summarized, and a superimposed distribution map is plotted with frequency on the horizontal axis and amplitude on the vertical axis. Each marked point in the figure represents a risk frequency point, and its height reflects the strongest interference intensity of any component at that frequency. The dense area of ​​multiple points represents the potential high-risk frequency band of the entire vehicle. By analyzing and processing the impedance resonant frequencies and amplitudes of all high-voltage components of the electric vehicle, the electromagnetic interference risk frequency-amplitude distribution map and distribution matrix of the entire vehicle are obtained.

[0128] Figure 5 This is a schematic diagram of the electromagnetic interference risk frequency-amplitude of an electric vehicle according to an embodiment of this application, as shown below. Figure 5 As shown, the frequency amplitude distribution diagram and distribution matrix provide a clear view of the risk frequency-amplitude distribution and the risk characteristic frequencies of each high-voltage component, enabling early identification of EMC risk frequencies for the entire vehicle, reducing interference troubleshooting time, and improving problem-solving efficiency. This method is a static test for electric vehicles and does not require the high cost of conducting tests in an anechoic chamber for the entire vehicle.

[0129] According to an embodiment of this application, a device for determining the electromagnetic risk frequency set of a vehicle is also provided. It should be noted that this device for determining the electromagnetic risk frequency set of a vehicle can be used to execute the method for determining the electromagnetic risk frequency set of a vehicle in the above embodiments.

[0130] Figure 6 This is a schematic diagram of a device for determining the electromagnetic risk frequency set of a vehicle according to an embodiment of this application, as shown below. Figure 6 As shown, the device 600 for determining the electromagnetic risk frequency set of the vehicle may include: a test unit 602, a first determining unit 604, and a second determining unit 608.

[0131] The test unit 602 is used to perform an impedance test on the target component in response to the voltage of the target component dropping to a preset voltage threshold, and to obtain the impedance test result of the target component. The impedance test result is used to indicate the risk level of the target component causing the electromagnetic compatibility performance of the vehicle to enter a failure state.

[0132] The first determining unit 604 is used to determine the frequency information and amplitude information of the target component based on the impedance test results. The frequency information is the resonant frequency of the electromagnetic noise generated by the target component that causes the electromagnetic compatibility performance to fail. The amplitude information is used to represent the interference intensity of the electromagnetic noise on the electromagnetic compatibility performance.

[0133] The second determining unit 606 is used to determine the electromagnetic risk frequency set of the vehicle based on frequency information and amplitude information, wherein the electromagnetic risk frequency set is the set of resonant frequencies that cause the electromagnetic compatibility performance to switch from a normal state to a failure state.

[0134] In this embodiment, the test unit 602 performs an impedance test on the target component in response to the voltage of the target component dropping to a preset voltage threshold, obtaining the impedance test result of the target component. The impedance test result is used to indicate the risk level of the target component causing the vehicle's electromagnetic compatibility performance to enter a failure state. Based on the impedance test result, the first determining unit 604 determines the frequency information and amplitude information of the target component. The frequency information is the resonant frequency of the electromagnetic noise generated by the target component that causes the electromagnetic compatibility performance to enter a failure state, and the amplitude information is used to indicate the interference intensity of the electromagnetic noise on the electromagnetic compatibility performance. Based on the frequency information and amplitude information, the second determining unit 606 determines the electromagnetic risk frequency set of the vehicle. The electromagnetic risk frequency set is the resonant frequency set that causes the electromagnetic compatibility performance to switch from a normal state to a failure state. This solves the technical problem of low efficiency in determining the electromagnetic risk frequency set of the vehicle and achieves the technical effect of improving the efficiency of determining the electromagnetic risk frequency set of the vehicle.

[0135] According to an embodiment of this application, a computer-readable storage medium is also provided, the storage medium including a stored program, wherein the program executes the methods described in the embodiments of this application.

[0136] According to an embodiment of this application, a processor is also provided for running a program, wherein the program executes the methods described in the embodiments of this application during runtime.

[0137] According to another aspect of the embodiments of this application, an electronic device is also provided. The electronic device includes a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to perform the methods described in the embodiments of this application.

[0138] According to another aspect of the embodiments of this application, a computer program product is also provided. This computer program product includes a computer program that, when executed by a processor, implements the methods described in the embodiments of this application.

[0139] According to another aspect of the embodiments of this application, a computer program product is also provided. This computer program product includes a computer program that, when executed by a processor, implements the methods described in the embodiments of this application.

[0140] According to another aspect of the embodiments of this application, a vehicle is also provided. The vehicle includes a memory and a processor, the memory storing a computer program, and the processor being configured to run the computer program to perform the methods described in the embodiments of this application.

[0141] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0142] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection can be through some interfaces; the indirect coupling or communication connection of units or modules can be electrical or other forms.

[0143] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0144] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as an application function unit.

[0145] If the integrated unit is implemented as an application function 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 this 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 an application product. This computer application product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0146] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A method for determining the electromagnetic risk frequency set of a vehicle, characterized in that, The vehicle includes a target component, the probability of which the target component generates electromagnetic noise is greater than the probability of other components in the vehicle generating electromagnetic noise. The method includes: In response to the voltage of the target component dropping to a preset voltage threshold, an impedance test is performed on the target component to obtain the impedance test result of the target component, wherein the impedance test result is used to indicate the degree of risk that the target component will cause the electromagnetic compatibility performance of the vehicle to enter a failure state; Based on the impedance test results, the frequency information and amplitude information of the target component are determined. The frequency information is the resonant frequency of the electromagnetic noise generated by the target component, which causes the electromagnetic compatibility performance to enter the failure state. The amplitude information is used to represent the interference intensity of the electromagnetic noise on the electromagnetic compatibility performance. Based on the frequency information and the amplitude information, the electromagnetic risk frequency set of the vehicle is determined, wherein the electromagnetic risk frequency set is the set of resonant frequencies that cause the electromagnetic compatibility performance to switch from the normal state to the failure state.

2. The method according to claim 1, characterized in that, The method further includes: In response to the instruction to determine the electromagnetic risk frequency set, a power-off operation is performed on the vehicle; After the vehicle completes the power-down operation, the target component is controlled to perform a discharge operation, and the voltage of the target component after the discharge operation is performed is acquired.

3. The method according to claim 2, characterized in that, Obtaining the voltage of the target component after performing the discharge operation includes: In response to the target component completing the discharge operation, the high-voltage interlock in the vehicle is disconnected, and the high-voltage power supply harness of the target component is disconnected. In response to the completion of the disconnection operation on the high-voltage interlock and the high-voltage power supply harness, the voltage is detected from the power port of the target component.

4. The method according to claim 1, characterized in that, The method further includes: The target component is connected to the vector network analyzer via an RF coaxial cable; The RF coaxial cable and the vector network analyzer are calibrated to obtain the calibrated RF coaxial cable and the calibrated vector network analyzer.

5. The method according to claim 4, characterized in that, In response to a voltage drop of the target component to a preset voltage threshold, an impedance test is performed on the target component to obtain the impedance test results, including: Set the test parameters of the calibrated vector network analyzer; According to the test parameters, the calibrated vector network analyzer is controlled to perform impedance testing on the target component, and the impedance test results are obtained.

6. The method according to claim 1, characterized in that, The impedance test result is an impedance curve, which represents the impedance amplitude and phase change at different frequencies. Based on the impedance test result, the frequency information and amplitude information of the target component are determined, including: The frequency information is extracted from the impedance curve; The amplitude information is determined based on the frequency information.

7. The method according to claim 6, characterized in that, Determining the amplitude information based on the frequency information includes: The amplitude information is determined by the average of the amplitudes corresponding to the frequency information and the amplitudes corresponding to the frequencies adjacent to the frequency information.

8. The method according to any one of claims 1 to 7, characterized in that, Based on the frequency information and the amplitude information, the electromagnetic risk frequency set of the vehicle is determined, including: Based on the frequency information and the amplitude information, a distribution map and a distribution matrix of the vehicles are constructed. The distribution map is used to represent the electromagnetic interference risk intensity corresponding to frequency points with different frequency information, and the distribution matrix represents the correspondence between the interference risk amplitude of the target component at different frequency points. Based on the distribution map and the distribution matrix, the electromagnetic risk frequency set is determined.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored executable program, wherein, when the executable program is executed, it controls the device on which the storage medium is located to perform the method according to any one of claims 1 to 8.

10. A vehicle, characterized in that, The method includes a memory and a processor, wherein the memory stores a computer program and the processor is configured to run the computer program to perform the method according to any one of claims 1 to 8.

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