Shaft voltage suppression method and device of motor system, electronic equipment and storage medium

Abstract

The invention discloses a shaft voltage suppression method and device of a motor system, electronic equipment and a storage medium. The method comprises the steps that a motor shaft voltage simulation model and an electromagnetic compatibility simulation analysis model of the motor system are obtained, and the motor shaft voltage simulation model is used for representing an equivalent circuit model of parasitic capacitance generating shaft voltage in the motor system; the electromagnetic compatibility simulation analysis model is used for representing a simulation analysis model obtained by carrying out electromagnetic compatibility integration on equivalent circuit models of a plurality of components in the motor system; based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model, performing integrated simulation on the motor system to obtain a shaft voltage simulation integrated model of the motor system; and based on the shaft voltage simulation integration model, screening a plurality of shaft voltage suppression strategies in a preset shaft voltage suppression strategy set to obtain a target shaft voltage suppression strategy. According to the invention, the technical problem of poor suppression effect of suppressing the shaft voltage of the motor system in the prior art is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicles, in particular to a shaft voltage suppression method and device of a motor system, an electronic device and a storage medium. BACKGROUND

[0002] With the rapid development of new energy vehicles, the motor system as an important part of new energy vehicles faces technical challenges in electromagnetic compatibility, including the shaft voltage problem in electromagnetic compatibility. The shaft voltage is derived from the common-mode voltage generated by the high-frequency switching action of the inverter of the motor system, and is formed between the bearing and the rotor through the complex stray capacitance network inside the motor system. After a long period of action, it leads to motor bearing electric corrosion, aggravates wear and tear, produces noise and even abnormal noise, which can seriously affect user experience and the safety of the motor system of the vehicle.

[0003] The shaft voltage suppression strategies of the motor system in the related art are diversified, which makes it difficult to determine a more appropriate shaft voltage suppression strategy for the motor system, resulting in blindness in the design of the motor system. It is often found that the shaft voltage suppression effect is not good after the design of the motor system, and repeated sampling and testing are required, which is time-consuming and laborious. That is, the suppression effect of suppressing the shaft voltage of the motor system in the related art is poor.

[0004] In view of the above problems, no effective solution has been proposed so far. SUMMARY

[0005] The embodiments of the present application provide a shaft voltage suppression method, device, electronic device and storage medium of a motor system to at least solve the technical problem of poor suppression effect of suppressing the shaft voltage of the motor system in the related art.

[0006] According to an aspect of an embodiment of the present application, a shaft voltage suppression method of a motor system is provided, comprising: obtaining a motor shaft voltage simulation model and an electromagnetic compatibility simulation analysis model of the motor system, wherein the motor shaft voltage simulation model is used to represent an equivalent circuit model of a parasitic capacitance that generates a shaft voltage in the motor system, the shaft voltage is used to represent a voltage between a bearing and a rotor in the motor system, and the electromagnetic compatibility simulation analysis model is used to represent a simulation analysis model obtained by integrating equivalent circuit models of a plurality of components in the motor system; based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model, integrated simulation is performed on the motor system to obtain a shaft voltage simulation integrated model of the motor system; based on the shaft voltage simulation integrated model, a plurality of shaft voltage suppression strategies in a preset shaft voltage suppression strategy set are screened to obtain a target shaft voltage suppression strategy, wherein the target shaft voltage suppression strategy is used to guide the shaft voltage suppression of the motor system.

[0007] In the embodiment of the present application, the motor shaft voltage simulation model of the motor system of the vehicle is obtained, comprising: simulating the motor structure of the motor system by using a preset simulation software to obtain a parasitic capacitance, wherein the parasitic capacitance comprises at least one of the capacitance between the stator coil and the stator, the capacitance between the stator coil and the rotor, the capacitance between the stator and the rotor, and the capacitance between the bearing and the rotor; and constructing the motor shaft voltage simulation model based on the parasitic capacitance and position data of the parasitic capacitance, wherein the position data is used to represent the relative position of the parasitic capacitance in the motor system.

[0008] In the embodiment of the present application, the electromagnetic compatibility simulation analysis model of the motor system of the vehicle is obtained, comprising: obtaining equivalent circuit models of a plurality of components in the motor system, wherein the plurality of components comprise at least two of the following: a shielded cable, a DC bus capacitor, a power module, an inverter housing and a motor in the motor system; and performing electromagnetic compatibility integration on the equivalent circuit models of the plurality of components to obtain the electromagnetic compatibility simulation analysis model.

[0009] In the embodiment of the present application, the equivalent circuit model of the shielded cable in the motor system is obtained, comprising: obtaining size parameters of the shielded cable; extracting parasitic parameters of the shielded cable to obtain shielded cable parasitic parameters, wherein the shielded cable parasitic capacitance comprises at least one of the following: equivalent resistance parameters, capacitance parameters, self-inductance parameters and mutual inductance parameters; and constructing the equivalent circuit model of the shielded cable based on the size parameters and the shielded cable parasitic parameters.

[0010] In the embodiment of the present application, the equivalent circuit model of the power module in the motor system is obtained, comprising: obtaining module manual data and double pulse test data of the power module, wherein the module manual data is used to represent product data recorded in the product manual of the power module, and the double pulse test data is used to represent test data obtained by performing pulse test on the power module based on two consecutive pulse signals; and constructing the equivalent circuit model of the power module based on the module manual data and the double pulse test data.

[0011] In the embodiment of the present application, the equivalent circuit model of the inverter housing in the motor system is obtained, comprising: obtaining a three-dimensional simulation model of the inverter housing; determining passive linear element parameters between different metals of the inverter housing and port parasitic parameters between different ports based on the three-dimensional simulation model, wherein the passive linear element parameters comprise at least one of the following: resistance parameters, inductance parameters and capacitance parameters; and constructing the equivalent circuit model of the inverter housing based on the passive linear element parameters and the port parasitic parameters.

[0012] In the embodiment of the present application, the shaft voltage simulation integrated model of the motor system is obtained by integrating simulation based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model, including: obtaining an initial shaft voltage simulation integrated model by integrating simulation based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model; testing the motor system to obtain actual shaft voltage parameters of the motor system; obtaining simulation shaft voltage parameters by simulating and testing the motor system based on the initial shaft voltage simulation integrated model; and obtaining the shaft voltage simulation integrated model based on the initial shaft voltage simulation integrated model, the actual shaft voltage parameters and the simulation shaft voltage parameters.

[0013] In the embodiment of the present application, the shaft voltage simulation integrated model is obtained based on the initial shaft voltage simulation integrated model, the actual shaft voltage parameters and the simulation shaft voltage parameters, including: determining a parameter deviation between the actual shaft voltage parameters and the simulation shaft voltage parameters; determining the initial shaft voltage simulation integrated model as the shaft voltage simulation integrated model when the parameter deviation is less than a preset deviation; and adjusting model parameters of the initial shaft voltage simulation integrated model to obtain the shaft voltage simulation integrated model when the parameter deviation is greater than or equal to the preset deviation.

[0014] According to another aspect of the embodiment of the present application, a motor system shaft voltage suppression device is also provided, including: an acquisition module, configured to acquire a motor shaft voltage simulation model and an electromagnetic compatibility simulation analysis model of a motor system of a vehicle, wherein the motor shaft voltage simulation model is used to represent an equivalent circuit model of a parasitic capacitance generating shaft voltage in the motor system, the shaft voltage is used to represent a voltage between a bearing and a rotor in the motor system, and the electromagnetic compatibility simulation analysis model is used to represent a simulation analysis model obtained by performing electromagnetic compatibility integration on equivalent circuit models of multiple components in the motor system; a simulation module, configured to perform integrated simulation on the motor system based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model to obtain a shaft voltage simulation integrated model of the motor system; and a screening module, configured to screen multiple shaft voltage suppression strategies in a preset shaft voltage suppression strategy set based on the shaft voltage simulation integrated model to obtain a target shaft voltage suppression strategy, wherein the target shaft voltage suppression strategy is used to guide shaft voltage suppression on the motor system.

[0015] According to another aspect of the embodiment of the present application, an electronic device is also provided, including: a memory storing an executable program; and a processor configured to run the program, wherein the program performs the method in each embodiment of the present application when running.

[0016] According to another aspect of the embodiment of the present application, a computer readable storage medium is also provided, including a stored executable program, wherein the computer readable storage medium controls a device where the computer readable storage medium is located to perform the method in each embodiment of the present application when the executable program runs.

[0017] According to another aspect of the embodiments of the present application, a computer program product is also provided, which comprises a computer program, and the computer program, when executed by a processor, implements the method in various embodiments of the present application.

[0018] According to another aspect of the embodiments of the present application, a computer program product is also provided, which comprises a non-volatile computer readable storage medium, and the non-volatile computer readable storage medium stores a computer program, and the computer program, when executed by a processor, implements the method in various embodiments of the present application.

[0019] According to another aspect of the embodiments of the present application, a computer program is also provided, and the computer program, when executed by a processor, implements the method in various embodiments of the present application.

[0020] In the embodiments of the present application, a motor shaft voltage simulation model and an electromagnetic compatibility simulation analysis model of a motor system are obtained, wherein the motor shaft voltage simulation model is used to represent an equivalent circuit model of a parasitic capacitor in the motor system that generates shaft voltage, the shaft voltage is used to represent a voltage between a bearing and a rotor in the motor system, and the electromagnetic compatibility simulation analysis model is used to represent a simulation analysis model obtained by integrating equivalent circuit models of multiple components in the motor system; based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model, integrated simulation is performed on the motor system to obtain a shaft voltage simulation integrated model of the motor system; and based on the shaft voltage simulation integrated model, multiple shaft voltage suppression strategies in a preset shaft voltage suppression strategy set are screened to obtain a target shaft voltage suppression strategy, wherein the target shaft voltage suppression strategy is used to guide shaft voltage suppression on the motor system. By integrating the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model of the motor system, the motor shaft voltage simulation model focuses on accurate modeling of the parasitic capacitor in the motor system, and can truly reflect the generation mechanism of the shaft voltage. The combined electromagnetic compatibility simulation analysis model includes electromagnetic coupling effects between multiple components in the motor system, and through integrated simulation, a shaft voltage simulation integrated model that more comprehensively reflects electromagnetic compatibility characteristics and shaft voltage characteristics of the motor system is constructed, which can predict the shaft voltage and reflect the influence of each component on the shaft voltage under complex working conditions, so that the shaft voltage prediction is more accurate. Based on the shaft voltage simulation integrated model, a target shaft voltage suppression strategy suitable for the motor system is screened, the shaft voltage suppression effect of each shaft voltage suppression strategy can be quantitatively evaluated, the prediction advantage of the shaft voltage simulation integrated model is fully utilized, it is ensured that the selected target shaft voltage suppression strategy can effectively address the shaft voltage problem in the motor system, the suppression effect is more optimal, blind hardware modification and cost waste are avoided, and thus the technical problem of poor suppression effect of the shaft voltage in the motor system in the related art is solved. BRIEF DESCRIPTION OF DRAWINGS

[0021] The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings:

[0022] Figure 1 is a flow chart of a method for suppressing shaft voltage of a motor system according to an embodiment of the application;

[0023] Figure 2 is a schematic diagram of an optional process for suppressing shaft voltage of a motor system according to an embodiment of the application;

[0024] Figure 3 is a schematic diagram of an optional parasitic capacitance of a motor system according to an embodiment of the application;

[0025] Figure 4 is a schematic diagram of an optional motor shaft voltage simulation model according to an embodiment of the application;

[0026] Figure 5 is a schematic diagram of a device for suppressing shaft voltage of a motor system according to an embodiment of the application. DETAILED DESCRIPTION

[0027] In order to make the persons skilled in the art better understand the application, the technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only a part of the embodiments of the application, but not all the embodiments of the application. Based on the embodiments in the application, all the other embodiments obtained by those skilled in the art without creative work should belong to the corresponding scope of the application.

[0028] It should be noted that the terms "first", "second", and the like in the specification and claims of the application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or a chronological sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to the process, method, product or device.

[0029] According to an aspect of the embodiments of the present application, there is provided a method for suppressing shaft voltage of a motor system. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described herein can be executed in an order different from that shown.

[0030] Figure 1 is a flowchart of a method for suppressing shaft voltage of a motor system according to an embodiment of the present application, as shown in Figure 1 The method comprises the following steps:

[0031] In step S102, a motor shaft voltage simulation model and an electromagnetic compatibility simulation analysis model of the motor system are obtained.

[0032] The motor shaft voltage simulation model is used to represent an equivalent circuit model of a parasitic capacitance in the motor system that generates shaft voltage, the shaft voltage is used to represent a voltage between a bearing and a rotor in the motor system, and the electromagnetic compatibility simulation analysis model is used to represent a simulation analysis model obtained by integrating equivalent circuit models of multiple components in the motor system.

[0033] The motor system described above can refer to an overall system composed of a motor of a vehicle and related auxiliary equipment, and can include but is not limited to a motor, an inverter, a DC bus capacitor, a power module, a shielded cable, a motor housing, and other components that can affect the performance of the system.

[0034] The motor shaft voltage simulation model described above can refer to a simulation model established for the motor shaft voltage phenomenon. The motor shaft voltage is mainly generated by the parasitic capacitance inside the motor under the action of the common-mode voltage. The motor shaft voltage simulation model can be used to simulate and predict the behavior of the motor shaft voltage under different working conditions.

[0035] The electromagnetic compatibility simulation analysis model described above can refer to a simulation model that comprehensively considers the mutual influence between electrical and electronic components in the motor system. It includes the characteristics of each component of the motor system, and also considers electromagnetic interference and electromagnetic compatibility between components. The electromagnetic compatibility simulation analysis model can integrate the main components in the motor system, such as shielded cables, DC bus capacitors, power modules, inverter housings, and motors, into circuit elements such as resistors, inductors, and capacitors for integrated analysis, to predict and improve the performance of the motor system in the actual electromagnetic environment, and to ensure that each component can still work stably in the presence of electromagnetic interference.

[0036] In an optional embodiment, simulation software can be used to analyze the motor system structure in detail and extract parameters of various parasitic capacitances. According to the positions and sizes of the parasitic capacitances, a motor shaft voltage simulation model can be constructed, which can accurately reflect the generation mechanism of the shaft voltage during motor operation. An excitation source can be set, which can be the common-mode voltage of the motor system, to simulate the actual operating environment and observe and analyze the dynamic changes of the shaft voltage. An electromagnetic compatibility simulation analysis model can also be constructed. Specifically, equivalent circuit models of various components in the motor system can be established, which can include but are not limited to shielding cables, DC bus capacitors, power modules, inverter housings, and circuit characteristics of the motor itself. Parasitic parameters such as the equivalent resistance, capacitance, self-inductance, and mutual inductance of the shielding cable, the data manual parameters and test data of the power module, etc. can be extracted through software. The equivalent circuit models of various components are integrated in the simulation environment to construct a comprehensive electromagnetic compatibility simulation model for evaluating and improving the performance of the entire motor system in the electromagnetic environment.

[0037] In the above process, by obtaining the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model of the motor system, the size and trend of the motor shaft voltage of the motor system under specific working conditions can be accurately predicted, which helps to prevent bearing damage caused by excessive shaft voltage. The electromagnetic compatibility simulation analysis model enables users to consider the interaction between components from the system level and make more detailed and comprehensive improvements to improve the electromagnetic compatibility and stability of the motor system as a whole.

[0038] Step S104, based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model, the motor system is simulated to obtain the shaft voltage simulation integrated model of the motor system.

[0039] The above shaft voltage simulation integrated model can refer to a system-level simulation model that combines the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model and can comprehensively reflect the shaft voltage behavior of the motor system in the electromagnetic environment. The shaft voltage simulation integrated model considers the generation mechanism of the shaft voltage and also considers the electromagnetic compatibility between components in the motor system, which can more accurately predict the shaft voltage changes of the motor system and the overall electromagnetic interference response of the motor system under actual working conditions.

[0040] In an alternative embodiment, an integrated simulation of the motor system can be performed based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model to obtain a shaft voltage simulation integrated model. Specifically, the established motor shaft voltage simulation model contains the equivalent circuit information of the parasitic capacitance that generates shaft voltage inside the motor. The electromagnetic compatibility simulation analysis model contains the equivalent circuit model of the electrical elements in the motor system and the electromagnetic coupling relationship between the electrical elements. The motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model are integrated in the simulation software, and by connecting common components or circuit nodes, a system-level simulation shaft voltage simulation integrated model can be created. In the integrated shaft voltage simulation integrated model, the actual working parameters of the motor system can be input, including the power supply voltage, working frequency, load condition, etc. The operation of the motor system under various working conditions, including at high switching frequency and high bus voltage, can be simulated. And the voltage change between the motor bearings, i.e. the behavior of the shaft voltage, and the electromagnetic compatibility performance of the entire motor system can be recorded and analyzed.

[0041] In the above process, through integrated simulation, a more comprehensive view of the motor system behavior can be obtained, including the generation of shaft voltage and electromagnetic compatibility evaluation, which helps to identify potential system-level problems. The shaft voltage simulation integrated model can provide accurate shaft voltage prediction and electromagnetic compatibility evaluation, facilitating further improvement of the motor system and improving the reliability and performance of the motor system in actual application.

[0042] Step S106, based on the shaft voltage simulation integrated model, screening multiple shaft voltage suppression strategies in the preset shaft voltage suppression strategy set to obtain a target shaft voltage suppression strategy.

[0043] The target shaft voltage suppression strategy is used to guide the shaft voltage suppression of the motor system.

[0044] The above-mentioned preset shaft voltage suppression strategy set can refer to a set of a series of designed shaft voltage suppression schemes. These shaft voltage suppression strategies can be formulated on the basis of theory or preliminary research, aiming to reduce the shaft voltage between the bearing and the rotor in the motor system. The preset shaft voltage suppression strategy set includes a variety of different shaft voltage suppression strategies, such as changing material properties, adjusting electrical parameters, introducing additional electrical elements such as filters, capacitors, resistors, or other structural changes, including solving the technical problem of excessive shaft voltage from different angles.

[0045] The above-mentioned target shaft voltage suppression strategy can refer to a specific shaft voltage suppression strategy suitable for the current motor system design determined through a series of evaluation and screening processes. The target shaft voltage suppression strategy can meet the demand of reducing the shaft voltage of the motor system, while taking into account the overall performance of the motor system and other design constraints.

[0046] In an alternative embodiment, a series of shaft voltage suppression strategies can be developed according to the characteristics of the motor system, working conditions and design goals, which can include the use of conductive grease, installation of grounded carbon brush, adjustment of the capacitance value between the bearing and the rotor, improvement of the modulation strategy of the inverter, etc. Each shaft voltage suppression strategy in the preset shaft voltage suppression strategy set has a detailed description. Then, the constructed shaft voltage simulation integrated model can be used to simulate a plurality of shaft voltage suppression strategies in the preset shaft voltage suppression strategy set. The changes in the shaft voltage of the motor system before and after the implementation of various shaft voltage suppression strategies can be recorded and compared, while the influence on the electromagnetic compatibility, efficiency, cost and other indicators of the motor system is monitored. Quantitative and qualitative evaluation methods, including statistical analysis of simulation results, compliance evaluation with design goals, cost-benefit analysis, etc. can be used to evaluate the effectiveness of each shaft voltage suppression strategy. According to the evaluation results, the shaft voltage suppression strategies that can significantly reduce the shaft voltage and do not cause negative effects on the motor system can be selected as the target shaft voltage suppression strategy. Further improvements can be made, including fine-tuning of strategy parameters, combining the advantages of two or more strategies, or evaluating the stability of candidate strategies under different working conditions.

[0047] In the above process, the shaft voltage simulation integrated model is used to virtually test a plurality of shaft voltage suppression strategies, which improves the screening efficiency and reduces resource waste compared to physically testing each prototype one by one. The shaft voltage simulation integrated model can accurately predict the actual influence of each shaft voltage suppression strategy on the shaft voltage of the motor system and the potential effect on other performance indicators of the motor system. Based on the shaft voltage simulation integrated model, the preset shaft voltage suppression strategy set is screened and the target shaft voltage suppression strategy is determined, which provides an efficient analysis tool and decision support framework for motor system shaft voltage suppression.

[0048] In the embodiment of the present application, the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model of the motor system are obtained, wherein the motor shaft voltage simulation model is used to represent the equivalent circuit model of the parasitic capacitance in the motor system, the shaft voltage is used to represent the voltage between the bearing and the rotor in the motor system, and the electromagnetic compatibility simulation analysis model is used to represent the simulation analysis model obtained by integrating the equivalent circuit models of the plurality of components in the motor system; based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model, the motor system is integrated and simulated to obtain a shaft voltage simulation integrated model of the motor system; based on the shaft voltage simulation integrated model, a plurality of shaft voltage suppression strategies in a preset shaft voltage suppression strategy set are screened to obtain a target shaft voltage suppression strategy, wherein the target shaft voltage suppression strategy is used to guide the shaft voltage suppression of the motor system. Through the integration of the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model of the motor system, the motor shaft voltage simulation model focuses on the accurate modeling of the parasitic capacitance in the motor system, and can truly reflect the generation mechanism of the shaft voltage. The combined electromagnetic compatibility simulation analysis model includes the electromagnetic coupling effect between the plurality of components in the motor system. Through integration simulation, a shaft voltage simulation integrated model that more comprehensively reflects the electromagnetic compatibility characteristics and the shaft voltage characteristics of the motor system is constructed, which can predict the shaft voltage and reflect the influence of each component on the shaft voltage under complex working conditions, so that the shaft voltage prediction is more accurate. Based on the shaft voltage simulation integrated model, the target shaft voltage suppression strategy suitable for the motor system is screened out, the shaft voltage suppression effect of each shaft voltage suppression strategy can be quantitatively evaluated, the prediction advantage of the shaft voltage simulation integrated model is fully utilized, and it is ensured that the selected target shaft voltage suppression strategy can effectively address the shaft voltage problem in the motor system, so that the suppression effect is more optimal, blind hardware modification and cost waste are avoided, and the technical problem of poor suppression effect of the shaft voltage suppression of the motor system in the related art is solved.

[0049] In the embodiment of the present application, the motor shaft voltage simulation model of the motor system of the vehicle is obtained, including: using a preset simulation software to simulate the motor structure of the motor system to obtain a parasitic capacitance, wherein the parasitic capacitance includes at least one of the capacitance between the stator coil and the stator, the capacitance between the stator coil and the rotor, the capacitance between the stator and the rotor, and the capacitance between the bearing and the rotor; based on the parasitic capacitance and position data of the parasitic capacitance, a motor shaft voltage simulation model is constructed, wherein the position data is used to represent the relative position of the parasitic capacitance in the motor system.

[0050] The above-mentioned parasitic capacitance can refer to a kind of capacitance effect existing in the process of circuit design or manufacturing due to the nature of material, structure layout or coupling effect between components. The parasitic capacitance can be generated by the motor structure itself, for example, the gap or material interface between the stator coil and the stator, the stator coil and the rotor, the stator and the rotor, and the bearing and the rotor, to form a capacitance effect.

[0051] The position data described above can refer to data for describing the specific position and relative layout of the parasitic capacitance in the motor system in the motor structure, can include the spatial relationship between the parasitic capacitance and other components of the motor, such as distance, angle, direction, etc., and can also include the physical position of the capacitance itself, such as data for whether it is at the front end, rear end, center or edge of the motor, etc.

[0052] In an optional embodiment, a three-dimensional structural model of the motor system can be accurately modeled by using simulation software, including components such as the stator, rotor, coil, bearing, etc. In the simulation software, parasitic capacitance extraction can be performed on the motor system structure, which can include but is not limited to the capacitance between the stator coil and the stator, the capacitance between the stator coil and the rotor, the capacitance between the stator and the rotor, and the capacitance between the bearing and the rotor. Electromagnetic field simulation technology can be used to accurately calculate the parasitic capacitance between the components in the motor structure at the actual working frequency. The parasitic capacitance obtained and the relative position and layout information of the parasitic capacitance in the motor system can be collected and sorted. In the simulation environment, a motor shaft voltage simulation model for simulating the shaft voltage behavior can be constructed according to the parasitic capacitance and the position data of the parasitic capacitance, to ensure that the motor shaft voltage simulation model can truly reflect the physical structure and electrical characteristics of the motor.

[0053] In the above process, by accurately extracting the parasitic capacitance in the motor structure and constructing the motor shaft voltage simulation model based on the parasitic capacitance and the position data of the parasitic capacitance, the shaft voltage of the motor system under various working conditions can be more accurately predicted, which helps to prevent and suppress the shaft voltage.

[0054] In an embodiment of the present application, an electromagnetic compatibility simulation analysis model of a motor system of a vehicle is obtained, including: obtaining equivalent circuit models of a plurality of components in the motor system, wherein the plurality of components include at least two of the following: a shielded cable, a DC bus capacitor, a power module, an inverter housing, and a motor in the motor system; and performing electromagnetic compatibility integration on the equivalent circuit models of the plurality of components to obtain the electromagnetic compatibility simulation analysis model.

[0055] The shielded cable described above can refer to a specially designed cable that can achieve electromagnetic shielding, can include one or more conductor cores, and these cores can be wrapped with one or more layers of metal braid or metal foil, for blocking external electromagnetic interference from entering the motor system, while reducing the influence of electromagnetic interference generated inside the motor system on the outside.

[0056] The equivalent circuit model mentioned above can refer to a circuit model used to simplify a complex electromagnetic environment and components, and realize analysis in a circuit simulation software. The equivalent circuit model abstracts actual electrical components, such as a shielded cable, a DC bus capacitor, a power module, an inverter housing, and a motor, as basic elements in a circuit, such as a resistor, an inductor, a capacitor, and a power supply, so as to perform electromagnetic compatibility simulation and analysis.

[0057] In an optional embodiment, simulation software can be used to analyze multiple components in a motor system, and obtain equivalent circuit models of the multiple components in the motor system. Specifically, parasitic parameters of a shielded cable can be extracted, including equivalent resistance, capacitance, self-inductance, and mutual inductance, to reflect transmission characteristics of the shielded cable under high-frequency signals and shielding effects on electromagnetic interference. For components such as a DC bus capacitor, a power module, an inverter housing, and a motor, different methods and techniques can be used to extract equivalent circuit parameters. The equivalent circuit model of the DC bus capacitor can be established by specification parameters; the equivalent circuit model of the power module can be based on data manuals and actual test data; the equivalent circuit model of the inverter housing includes passive linear element parameters inside the structure; and the equivalent circuit model of the motor can consider electromagnetic impedance and parasitic parameters. Finally, the equivalent circuit models of the components mentioned above can be integrated in simulation software to construct a complete electromagnetic compatibility simulation analysis model of the motor system, which can consider physical connections and electromagnetic coupling between the components to ensure that the electromagnetic compatibility simulation analysis model can truly reflect behaviors of the motor system under actual electromagnetic environments. When the electromagnetic compatibility simulation analysis model is integrated, interactions between the shielded cable, the DC bus capacitor, the power module, the inverter housing, and the motor can be considered, including delays, attenuations, and reflections of signal transmission between the components, and formation and propagation of common-mode and differential-mode interference.

[0058] In the above process, by integrating equivalent circuit models of multiple components, the ability to perform electromagnetic compatibility analysis at the system level is obtained, which can evaluate overall performance of the entire motor system when facing electromagnetic interference. The electromagnetic compatibility simulation analysis model allows users to quickly adjust and test different design schemes in a virtual environment and evaluate influences on electromagnetic compatibility performance of the motor system.

[0059] In the embodiment of the application, the equivalent circuit model of the shielded cable in the motor system is obtained, including: obtaining size parameters of the shielded cable; performing parasitic parameter extraction on the shielded cable to obtain shielded cable parasitic parameters, wherein the shielded cable parasitic capacitance includes at least one of the following: equivalent resistance parameters, capacitance parameters, self-inductance parameters, and mutual inductance parameters; and constructing an equivalent circuit model of the shielded cable based on the size parameters and the shielded cable parasitic parameters.

[0060] The aforementioned dimensional parameters can refer to descriptive parameters of the shielded cable's dimensional characteristics, and may include the cable's length, inner and outer diameters, shielding layer thickness, distance between wire cores, and wire core diameter, etc.

[0061] The parasitic parameters of shielded cables mentioned above can refer to at least one of the equivalent resistance, capacitance, self-inductance, and mutual inductance parameters of the shielded cable. The equivalent resistance parameter can be the energy loss caused by the resistance of the cable's own material during conduction; the capacitance parameter can be the distributed capacitance between the cable and the external environment or its internal conductors, affecting signal delay and electromagnetic compatibility; the self-inductance parameter reflects the cable's ability to generate a magnetic field due to current changes in its own loop; and the mutual inductance parameter can be the influence between the parallel conductors of the cable, which can affect signal integrity in multi-cable cabling.

[0062] In one alternative embodiment, dimensional parameters such as the length, inner and outer diameters, and shielding layer thickness of the shielded cable, as well as relevant material properties such as dielectric constant and permeability, can be obtained by measuring or consulting data. Electromagnetic field simulation software can then be used to input these dimensional parameters to simulate and calculate various parasitic effects of the shielded cable under high-frequency conditions. Extracting equivalent resistance, capacitance, self-inductance, and mutual inductance parameters helps in understanding the cable's role in electromagnetic compatibility analysis. The extraction of parasitic parameters may include solving electromagnetic fields; software can be used to analyze based on equations and boundary conditions, considering factors such as cable geometry, material properties, and operating frequency. Next, based on the extracted dimensional and parasitic parameters, an equivalent circuit model of the shielded cable can be constructed using circuit simulation software. In this equivalent circuit model, the shielded cable is represented as a series of series resistors, capacitors, and inductors, and parallel mutual inductance branches. When constructing the equivalent circuit model of shielded cables, the termination conditions of the shielded cables and the influence of the surrounding environment can also be considered, such as the connection method between the cable and the inverter and the motor, as well as the relative position and arrangement with other cables, and their impact on parasitic parameters.

[0063] In the above process, by extracting parasitic parameters and constructing equivalent circuit models for shielded cables, the electromagnetic compatibility (EMC) performance of shielded cables in motor systems can be accurately evaluated, and the performance of shielded cables under high-frequency signals, including signal attenuation, reflection, crosstalk, and EMC performance, can be predicted. Integrating the equivalent circuit model of the shielded cable into the EMC simulation analysis model of the motor system can improve the overall EMC performance of the motor system, ensure stable operation of the motor system in complex electromagnetic environments, and reduce the impact of shaft voltage and electromagnetic interference.

[0064] In this embodiment of the invention, obtaining the equivalent circuit model of the power module in the motor system includes: obtaining the module manual data and double-pulse test data of the power module, wherein the module manual data is used to represent the product data recorded in the product manual of the power module, and the double-pulse test data is used to represent the test data obtained by performing pulse tests on the power module based on two consecutive pulse signals; and constructing the equivalent circuit model of the power module based on the module manual data and the double-pulse test data.

[0065] The module manual data mentioned above can refer to the product data sheet data provided by the power module manufacturer, which may include the electrical and physical parameters of the power module, such as rated voltage and current, switching frequency range, conduction loss and switching loss, equivalent series resistance, equivalent series inductance, insulation withstand voltage and operating temperature range, etc.

[0066] The aforementioned double-pulse test data can refer to test data used to evaluate the dynamic performance of power semiconductor devices. By applying two consecutive pulse signals to the power module, parameters of the power module during the turn-on and turn-off processes can be measured, such as turn-on time, turn-off time, overshoot voltage and current during turn-off, and switching losses.

[0067] In one optional embodiment, static and dynamic parameters of the power module, including rated voltage, current, switching frequency, equivalent series resistance, equivalent series inductance, insulation withstand voltage, and operating temperature range, can be extracted from the power module's product datasheet. A dual-pulse test circuit can be designed to generate two consecutive pulse signals to evaluate the dynamic performance of the power module during switching. Tests can be performed to record the power module's on-time, off-time, overshoot voltage and current, and switching losses under pulse signal excitation. The dual-pulse test data can be analyzed to understand the transient behavior and thermal performance of the power module under actual operating conditions. Then, combining the module datasheet and the dual-pulse test data, an equivalent circuit model of the power module can be constructed using circuit simulation software. The equivalent circuit model of the power module can include components representing static parameters, such as fixed capacitors and resistors, and components reflecting dynamic characteristics, such as switching elements, transient buffer capacitors, and switching loss models.

[0068] In the above process, based on the module manual data and double pulse test data, an equivalent circuit model of the power module is constructed, which can truly reflect the dynamic characteristics and switching performance of the power module under different operating conditions, and help to evaluate the electromagnetic compatibility performance and shaft voltage influence of the power module in the motor system.

[0069] In this embodiment of the invention, obtaining the equivalent circuit model of the inverter housing in the motor system includes: obtaining a three-dimensional simulation model of the inverter housing; based on the three-dimensional simulation model, determining the passive linear component parameters between different metals of the inverter housing and the port parasitic parameters between different ports, wherein the passive linear component parameters include at least one of the following: resistance parameters, inductance parameters, and capacitance parameters; and constructing the equivalent circuit model of the inverter housing based on the passive linear component parameters and the port parasitic parameters.

[0070] The aforementioned 3D simulation model refers to the simulation model created by performing 3D modeling and simulation analysis on the inverter housing. The constructed 3D simulation model can show in detail the internal structure of the inverter housing and the spatial layout of its various components, including the relative positions, contact areas, shapes, and dimensions of different metal parts.

[0071] The aforementioned passive linear component parameters refer to the equivalent resistance, inductance, and capacitance values ​​formed by the metal components inside the inverter housing due to their inherent characteristics and the spacing and contact methods between them. These values ​​can serve as the data basis for constructing the electromagnetic compatibility analysis model of the inverter housing.

[0072] The aforementioned port parasitic parameters can refer to the parasitic parameters that exist between different ports of the inverter housing due to factors such as wiring, connectors, and solder joints. These can include differential mode parasitic parameters and common mode parasitic parameters.

[0073] In one optional embodiment, 3D modeling software is used to simulate the internal structure of the inverter housing, including but not limited to the position and geometry of components such as metal parts, solder joints, connectors, and busbars. Then, electromagnetic compatibility analysis is performed on the 3D simulation model using electromagnetic simulation software to extract passive linear component parameters between the various metal parts. Alternatively, based on the 3D simulation model, the software's built-in parameter extraction tool can be used to calculate the equivalent resistance, inductance, and capacitance values ​​between different metal components in the inverter housing. Simultaneously, parasitic parameters between ports are extracted, including differential-mode and common-mode parasitic parameters, reflecting the complex electromagnetic coupling effects within the inverter housing. Next, the extracted passive linear component parameters and port parasitic parameters are input into circuit simulation software to construct an equivalent circuit model of the inverter housing. The equivalent circuit model of the inverter housing can include the electrical connections of the metal components, parasitic effects, and coupling paths between ports.

[0074] In the above process, an equivalent circuit model of the inverter housing is used to perform circuit-level electromagnetic compatibility analysis and evaluate the impact of the inverter housing on the motor system shaft voltage and overall electromagnetic compatibility performance. By constructing an equivalent circuit model of the inverter housing, the impact of the inverter housing on the motor system shaft voltage and electromagnetic compatibility performance can be accurately predicted.

[0075] In this embodiment of the invention, an integrated simulation is performed based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model to obtain an integrated shaft voltage simulation model of the motor system. This includes: performing an integrated simulation based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model to obtain an initial integrated shaft voltage simulation model; testing the motor system to obtain the actual shaft voltage parameters of the motor system; performing simulation testing on the motor system based on the initial integrated shaft voltage simulation model to obtain simulated shaft voltage parameters; and obtaining the integrated shaft voltage simulation model based on the initial integrated shaft voltage simulation model, the actual shaft voltage parameters, and the simulated shaft voltage parameters.

[0076] The aforementioned actual shaft voltage parameters can refer to the specific numerical parameters of the shaft voltage measured by testing equipment, such as an oscilloscope, under the actual operating conditions of the motor system.

[0077] The aforementioned simulated shaft voltage parameters can refer to the shaft voltage parameters that are theoretically predicted for the motor system shaft voltage, obtained by integrating the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model.

[0078] In one optional embodiment, the motor shaft voltage simulation model and the electromagnetic compatibility (EMC) simulation analysis model can be combined in circuit simulation software to form a comprehensive simulation environment that simulates the shaft voltage behavior of the motor system under various operating conditions. A high-precision oscilloscope or other professional testing equipment can be used to measure the shaft voltage of the actual operating motor system, recording the shaft voltage data under different operating conditions to obtain the actual shaft voltage parameters. The actual shaft voltage parameters provide realistic feedback on the motor system's shaft voltage, allowing for the evaluation of the accuracy of the initial shaft voltage simulation integrated model. In the initial shaft voltage simulation integrated model, the same operating conditions as the actual test can be set, including power supply voltage, frequency, load, etc., for simulation testing, and the predicted shaft voltage values ​​from the initial shaft voltage simulation integrated model can be recorded. By comparing the simulated shaft voltage parameters with the actual shaft voltage parameters, the predictive capability and accuracy of the initial shaft voltage simulation integrated model can be evaluated. If there is a significant difference between the simulated and actual shaft voltage parameters, the parameters in the initial shaft voltage simulation integrated model can be adjusted. Adjusted parameters may include parasitic capacitance values ​​in the motor shaft voltage model, passive linear component parameters in the EMC model, etc.

[0079] In the above process, the accuracy and applicability of the shaft voltage simulation integrated model can be effectively verified by comparing the actual shaft voltage parameters and the simulated shaft voltage parameters. Improvements and calibrations to the shaft voltage simulation integrated model ensure a more realistic reflection of the motor system's behavior and enhance the reliability of the predicted shaft voltage level.

[0080] In this embodiment of the invention, an integrated shaft voltage simulation model is obtained based on an initial shaft voltage simulation model, actual shaft voltage parameters, and simulated shaft voltage parameters. This includes: determining the parameter deviation between the actual shaft voltage parameters and the simulated shaft voltage parameters; if the parameter deviation is less than a preset deviation, determining the initial shaft voltage simulation model as the integrated shaft voltage simulation model; if the parameter deviation is greater than or equal to the preset deviation, adjusting the model parameters of the initial shaft voltage simulation model to obtain the integrated shaft voltage simulation model.

[0081] The aforementioned preset deviation refers to the standard deviation value set during the verification and adjustment of the motor shaft voltage simulation model. It can be used to measure whether the difference between the actual shaft voltage parameters and the simulated shaft voltage parameters is within an acceptable range.

[0082] In one optional embodiment, the parameter deviation between the actual shaft voltage parameters obtained from actual testing and the simulated shaft voltage parameters can be calculated. Then, based on the calculated parameter deviation, it can be determined whether the initial shaft voltage simulation integrated model meets the preset accuracy requirements. If the parameter deviation is less than the preset deviation, it can be determined that the initial shaft voltage simulation integrated model matches the actual situation, and the current initial shaft voltage simulation integrated model can be used as the shaft voltage simulation integrated model. If the parameter deviation is greater than or equal to the preset deviation, the model parameters of the initial shaft voltage simulation integrated model are adjusted. This may include adjusting the parasitic capacitance value in the motor shaft voltage model, the parameters of the passive linear components in the electromagnetic compatibility model, the parameters of the inverter control strategy, or adjusting the connection method of each component in the model to obtain a simulation effect closer to the actual shaft voltage parameters. The adjustment process may include multiple iterations and re-simulation. When the parameter deviation is less than the preset deviation, the current initial shaft voltage simulation integrated model can be used as the shaft voltage simulation integrated model.

[0083] In the above process, by setting preset deviations and calculating parameter deviations, it is possible to ensure that the prediction results of the shaft voltage simulation integrated model are close to the behavior of the actual motor system, significantly improving the reliability and practicality of the shaft voltage simulation integrated model in engineering design. By setting preset deviations and calculating parameter deviations, the accuracy of the motor shaft voltage simulation model is improved and the model is verified, enhancing the reliability of the simulation results.

[0084] The technical solution proposed in this application is described below with reference to an optional embodiment. This application proposes a method and system for suppressing shaft voltage in a motor system. The method analyzes the generation mechanism of shaft voltage, establishes a simulation model of motor shaft voltage based on the electromagnetic compatibility simulation analysis model of the motor system and the actual structure of the motor, and quickly and accurately evaluates the effectiveness of shaft voltage reduction measures through simulation. This saves prototyping and testing costs, guides product design, and is more suitable for engineering applications.

[0085] This application enables system-level simulation analysis, revealing complex coupling paths. The proposed system-level electromagnetic compatibility simulation analysis model calculates shaft voltage, considering the amplification effect of wave reflection and cable effects caused by impedance mismatch on the common-mode voltage at the motor terminals. It also accurately models parasitic parameters and coupling paths, thus predicting shaft voltage more precisely. This application can quantify the effectiveness of suppression measures. The proposed motor system shaft voltage suppression device and system analyze the shaft voltage generation mechanism, extract various coupling parameters within the motor, analyze the coupling relationships between different structures within the motor, and equate the coupling relationships between the motor components to electrical elements, obtaining a motor shaft voltage simulation model. A motor shaft voltage suppression method is proposed, and the simulation model allows for rapid risk assessment, saving prototyping and testing costs and guiding product design. The integrated shaft voltage simulation model in this application has high accuracy and simulation efficiency, can guide design, and has engineering application value. The simulation circuit and simulation model in this application have a clear topology and explicit physical meaning, enabling prediction of shaft voltage in the early stages of product design and providing improvement suggestions.

[0086] This application aims to suppress motor shaft voltage using modeling and simulation. The generation mechanism of shaft voltage is analyzed, along with the coupling relationships between various internal structures of the motor. Internal coupling parameters are extracted, and the coupling relationships between the internal components of the motor are equated to electrical components, thus obtaining a motor shaft voltage simulation model. The electromagnetic interference coupling mechanism of the motor system is analyzed. Based on a software platform, and considering the differential and common-mode interference loops and the coupling characteristics of components within those loops, equivalent circuits using resistors, inductors, and capacitors are used to construct the components and their distributed parameters. A mechanism-based electromagnetic compatibility simulation analysis model of the motor system is established and integrated with the aforementioned motor shaft voltage simulation model for simulation. Motor shaft voltage tests are conducted, and the simulation results are compared with experimental test results to adjust the model parameters of the integrated shaft voltage simulation model. Based on the integrated shaft voltage simulation model, measures to suppress shaft voltage are proposed. By modifying the device parameters or adding / removing devices in the integrated shaft voltage simulation model, rapid evaluation of the simulation-based shaft voltage suppression measures is achieved.

[0087] Figure 2 This is a schematic diagram of an optional shaft voltage suppression process for a motor system according to an embodiment of the present invention, such as... Figure 2As shown, a simulation model of the motor shaft voltage and an electromagnetic compatibility (EMC) simulation analysis model of the motor system are obtained. Based on the motor shaft voltage simulation model and the EMC simulation analysis model, an integrated simulation is performed to obtain an initial shaft voltage simulation integrated model. The motor system is tested to obtain the actual shaft voltage parameters of the motor system. Based on the initial shaft voltage simulation integrated model, the motor system is simulated and tested to obtain the simulated shaft voltage parameters. The parameter deviation between the actual shaft voltage parameters and the simulated shaft voltage parameters is determined. It is determined whether the parameter deviation is less than a preset deviation. If it is, the initial shaft voltage simulation integrated model is determined as the shaft voltage simulation integrated model; otherwise, the model parameters of the initial shaft voltage simulation integrated model are adjusted to obtain the shaft voltage simulation integrated model. Based on the shaft voltage simulation integrated model, multiple shaft voltage suppression strategies in the preset shaft voltage suppression strategy set are screened to obtain the target shaft voltage suppression strategy.

[0088] The specific implementation method of this application is as follows: A motor shaft voltage simulation model is established. The common-mode voltage of the motor system generates the shaft voltage through the voltage division of the parasitic capacitances inside the motor. To obtain the motor shaft voltage simulation model, the magnitude of each parasitic capacitance inside the motor can be obtained, and an accurate motor shaft voltage simulation model can be established based on the actual location of each parasitic capacitance in the motor. This application uses simulation software to extract the parasitic capacitances inside the motor by simulating the motor structure model. The main parasitic capacitances inside the motor include the capacitance between the stator coils and the stator, the capacitance between the stator coils and the rotor, the capacitance between the stator and the rotor, and the capacitance between the bearings and the rotor. Based on the extracted parasitic capacitances and their locations, an equivalent circuit model of the parasitic capacitances inside the motor is built, i.e., the motor shaft voltage simulation model. The voltage between the bearings and the rotor shaft is the shaft voltage, and the voltage between the stator coils and the stator is the common-mode voltage of the motor system. An excitation source is set at the common-mode voltage, and the input of the excitation source is obtained by testing with an oscilloscope.

[0089] Figure 3 This is a schematic diagram of the parasitic capacitance of an optional motor system according to an embodiment of the present invention, such as... Figure 3 As shown in the diagram, in the motor structure of the motor system, the parasitic capacitance may include the following: the capacitance C1 between stator coil E2 and stator E1, the capacitance C2 between stator E1 and rotor E3, the capacitance C3 between stator coil E2 and rotor E3, and the capacitance C4 between bearing E4 and rotor E3.

[0090] Figure 4 This is a schematic diagram of an optional motor shaft voltage simulation model according to an embodiment of the present invention. The diagram includes the capacitance C1 between stator coil E2 and stator E1, the capacitance C2 between stator E1 and rotor E3, the capacitance C3 between stator coil E2 and rotor E3, the capacitance C4 between bearing E4 and rotor E3, the shaft voltage Vb, and the common-mode voltage Vcom between stator coil E2 and stator E1.

[0091] The electromagnetic compatibility (EMC) simulation analysis model of the motor system is established and integrated. Based on the physical structure of the motor system, equivalent circuit models of each major component are established, including shielded cables, DC bus capacitors, power modules, inverter housings, and the motor. The EMC simulation analysis model of the motor system is built based on the arrangement and connection relationships of each component within the motor-inverter system. For shielded cable modeling, parasitic parameters are extracted based on the actual dimensions of the shielded cable, generating an equivalent circuit model including parameters such as equivalent resistance, capacitance, self-inductance, and mutual inductance. For DC bus capacitor modeling, both structural and electrical characteristics are considered. The equivalent circuit model of the DC bus capacitor can include differential-mode and common-mode equivalent circuits. Parameters such as DC bus capacitor capacitance, equivalent series resistance, and equivalent series inductance are extracted from the three-dimensional digital model of the DC bus capacitor. For power module modeling, based on the module manual data and double-pulse test data, a relatively accurate equivalent circuit model of the power module is established through debugging, adjustment, and comparison with actual measurements using a feature-based modeling module. The inverter housing is modeled, and based on the 3D simulation model, the resistance, inductance, and capacitance values ​​between pairs of metal components within the structure are extracted to obtain parasitic parameters between the positive and negative terminals of the busbar and between each pair of the three phase lines, as well as between each port and the main enclosure. Motor modeling is performed by determining the model order based on the motor's differential and common-mode impedance test results. Using the resonant peak and valley frequencies of the impedance curve, the inductance and capacitance values ​​are calculated, allowing the construction of the motor's equivalent circuit model. The equivalent circuit models of the various components established above can be integrated to obtain the electromagnetic compatibility simulation analysis model of the motor system.

[0092] Next, the electromagnetic compatibility simulation analysis model of the motor system is integrated with the motor shaft voltage simulation model and simulated to obtain the shaft voltage simulation results. Shaft voltage testing and comparison can be performed. The shaft voltage of the motor system can be tested using an oscilloscope, and the actual shaft voltage parameters and simulated shaft voltage parameters can be compared. If the comparison results are good and the parameter deviation is less than the preset deviation, the shaft voltage simulation integrated model does not need to be adjusted. If the parameter deviation is greater than or equal to the preset deviation, the model parameters of the shaft voltage simulation integrated model can be modified.

[0093] This application simulates shaft voltage suppression measures by adjusting the parasitic capacitance parameters of the motor in the shaft voltage simulation integrated model. For example, increasing the parasitic capacitance between the bearing and rotor simulates the use of conductive grease in the bearing. Using grease containing conductive fillers such as graphite and metal particles in the bearing reduces the shaft voltage amplitude, demonstrating the effectiveness of this measure in suppressing shaft voltage. Similarly, short-circuiting the parasitic capacitance between the bearing and rotor simulates the installation of a grounding carbon brush. The simulation shows the shaft voltage amplitude becomes zero, indicating that this measure provides a low-impedance path, thus eliminating shaft voltage. This simulation method allows for rapid and accurate evaluation of the effectiveness of shaft voltage reduction measures, saving prototyping and testing costs, guiding product design, and is suitable for engineering applications.

[0094] According to another aspect of the present invention, a shaft voltage suppression device for a motor system is also provided. This device can perform the shaft voltage suppression method for the motor system described in the above embodiments. The specific implementation method and preferred application scenarios are the same as those described in the above embodiments, and will not be repeated here.

[0095] Figure 5 This is a schematic diagram of a shaft voltage suppression device for a motor system according to an embodiment of this application, as shown below. Figure 5 As shown, the device includes the following: an acquisition module 502, a simulation module 504, and a screening module 506.

[0096] The acquisition module 502 is used to acquire the motor shaft voltage simulation model and electromagnetic compatibility (EMC) simulation analysis model of the vehicle's motor system. The motor shaft voltage simulation model represents the equivalent circuit model of the parasitic capacitance that generates shaft voltage in the motor system, and the shaft voltage represents the voltage between the bearing and the rotor in the motor system. The EMC simulation analysis model represents the simulation analysis model obtained by integrating the equivalent circuit models of multiple components in the motor system for EMC. The simulation module 504 is used to perform integrated simulation of the motor system based on the motor shaft voltage simulation model and the EMC simulation analysis model to obtain the integrated shaft voltage simulation model of the motor system. The filtering module 506 is used to filter multiple shaft voltage suppression strategies in a preset set of shaft voltage suppression strategies based on the integrated shaft voltage simulation model to obtain the target shaft voltage suppression strategy. The target shaft voltage suppression strategy is used to guide the shaft voltage suppression of the motor system.

[0097] The acquisition module is also used to simulate the motor structure of the motor system using preset simulation software to obtain parasitic capacitance. The parasitic capacitance includes at least one of the following: capacitance between stator coils and stator, capacitance between stator coils and rotor, capacitance between stator and rotor, and capacitance between bearing and rotor in the motor system. Based on the parasitic capacitance and its position data, a simulation model of motor shaft voltage is constructed, wherein the position data is used to characterize the relative position of the parasitic capacitance in the motor system.

[0098] The acquisition module is also used to acquire equivalent circuit models of multiple components in the motor system, wherein the multiple components include at least two of the following: shielded cables, DC bus capacitors, power modules, inverter housings, and motors in the motor system; and to perform electromagnetic compatibility integration on the equivalent circuit models of the multiple components to obtain an electromagnetic compatibility simulation analysis model.

[0099] The acquisition module is also used to acquire the size parameters of the shielded cable; extract parasitic parameters of the shielded cable to obtain the parasitic parameters of the shielded cable, wherein the parasitic capacitance of the shielded cable includes at least one of the following: equivalent resistance parameter, capacitance parameter, self-inductance parameter and mutual inductance parameter; and construct an equivalent circuit model of the shielded cable based on the size parameters and the parasitic parameters of the shielded cable.

[0100] The acquisition module is also used to acquire the module manual data and double-pulse test data of the power module. The module manual data represents the product data recorded in the product manual of the power module, and the double-pulse test data represents the test data obtained by performing pulse tests on the power module based on two consecutive pulse signals. Based on the module manual data and double-pulse test data, an equivalent circuit model of the power module is constructed.

[0101] The acquisition module is also used to acquire a three-dimensional simulation model of the inverter housing; based on the three-dimensional simulation model, it determines the passive linear component parameters between different metals of the inverter housing and the port parasitic parameters between different ports, wherein the passive linear component parameters include at least one of the following: resistance parameters, inductance parameters and capacitance parameters; based on the passive linear component parameters and port parasitic parameters, it constructs an equivalent circuit model of the inverter housing.

[0102] The simulation module is also used to perform integrated simulation based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model to obtain the initial shaft voltage simulation integrated model; to test the motor system to obtain the actual shaft voltage parameters of the motor system; to perform simulation testing on the motor system based on the initial shaft voltage simulation integrated model to obtain the simulated shaft voltage parameters; and to obtain the shaft voltage simulation integrated model based on the initial shaft voltage simulation integrated model, the actual shaft voltage parameters, and the simulated shaft voltage parameters.

[0103] The simulation module is also used to determine the parameter deviation between the actual shaft voltage parameters and the simulated shaft voltage parameters; if the parameter deviation is less than the preset deviation, the initial shaft voltage simulation integrated model is determined as the shaft voltage simulation integrated model; if the parameter deviation is greater than or equal to the preset deviation, the model parameters of the initial shaft voltage simulation integrated model are adjusted to obtain the shaft voltage simulation integrated model.

[0104] Embodiments of this application also provide an electronic device, including: a memory storing an executable program; and a processor for running the program, wherein the program executes the methods in various embodiments of the present invention during runtime.

[0105] The aforementioned memory can refer to devices inside a computer used to store data and programs, including RAM, hard disks, etc. RAM can be used to temporarily store running programs and data, while hard disks can be used to store programs and data long-term. Memory enables the computer to read and write data and execute programs. The aforementioned processor is responsible for executing instructions in computer programs and performing data processing. It can also be responsible for controlling and executing various operations, including arithmetic operations, logical operations, and data transmission.

[0106] Embodiments of this application also provide a computer-readable storage medium including a stored executable program, wherein, when the executable program is running, it controls the device where the computer-readable storage medium is located to perform the methods of various embodiments of the present invention.

[0107] The aforementioned computer storage media can refer to the media used in computer memory to store certain discontinuous physical quantities. Computer storage media mainly include semiconductors, magnetic cores, magnetic drums, magnetic tapes, laser discs, etc. Computer-readable storage media include stored programs, which can be a set of instructions that a computer can recognize and execute, running on an electronic computer to meet certain information needs.

[0108] Embodiments of this application also provide a computer program product, including a computer program that, when executed by a processor, implements the methods of various embodiments of the present invention.

[0109] The aforementioned computer program products can refer to software programs that have been written, tested, and released, and can run on computers or other devices. Computer program products can include application programs, operating systems, utility software, etc., used to achieve specific functions or solve specific problems.

[0110] Embodiments of this application also provide a computer program product, including a non-volatile computer-readable storage medium for storing a computer program that, when executed by a processor, implements the methods in various embodiments of the present invention.

[0111] The aforementioned non-volatile computer-readable storage medium can refer to a medium for storing data. Non-volatile computer-readable storage media can retain data without loss when power is off and can be used to store long-term data, such as operating systems, applications, and user files. Non-volatile storage media can include hard disk drives, solid-state drives, optical disks, and flash memory storage devices, etc.

[0112] Embodiments of this application also provide a computer program that, when executed by a processor, implements the methods described in the various embodiments of the present invention.

[0113] The aforementioned computer program can refer to a set of instructions used to tell the computer to perform specific tasks or operations. Computer programs can be written by programmers using specific programming languages ​​and can include algorithms, data structures, logic, and control flow. Computer programs can be used for a variety of purposes, including application software, operating systems, etc.

[0114] In the above embodiments of the present invention, 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.

[0115] 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 illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For example, 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 between units or modules can be electrical or other forms.

[0116] 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.

[0117] Furthermore, the functional units in the various embodiments of the present invention 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 a software functional unit.

[0118] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software 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 the present invention. 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.

[0119] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for suppressing shaft voltage in a motor system, characterized in that, include: A simulation model of the motor shaft voltage and an electromagnetic compatibility (EMC) simulation analysis model of the motor system are obtained. The motor shaft voltage simulation model is used to represent the equivalent circuit model of the parasitic capacitance that generates the shaft voltage in the motor system. The shaft voltage is used to represent the voltage between the bearing and the rotor in the motor system. The EMC simulation analysis model is used to represent the simulation analysis model obtained by integrating the equivalent circuit models of multiple components in the motor system with EMC. Based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model, the motor system is integrated for simulation to obtain the integrated shaft voltage simulation model of the motor system. Based on the shaft voltage simulation integration model, multiple shaft voltage suppression strategies in the preset shaft voltage suppression strategy set are screened to obtain the target shaft voltage suppression strategy, wherein the target shaft voltage suppression strategy is used to guide the shaft voltage suppression of the motor system.

2. The shaft voltage suppression method for a motor system according to claim 1, characterized in that, Obtain the simulation model of the motor shaft voltage of the vehicle's motor system, including: Using preset simulation software, the motor structure of the motor system is simulated to obtain the parasitic capacitance, wherein the parasitic capacitance includes at least one of the following: the capacitance between the stator coil and the stator in the motor system, the capacitance between the stator coil and the rotor, the capacitance between the stator and the rotor, and the capacitance between the bearing and the rotor; Based on the parasitic capacitance and its location data, a simulation model of the motor shaft voltage is constructed, wherein the location data is used to characterize the relative position of the parasitic capacitance in the motor system.

3. The shaft voltage suppression method for a motor system according to claim 1 or 2, characterized in that, Obtain the electromagnetic compatibility simulation analysis model of the vehicle's motor system, including: Obtain the equivalent circuit model of the plurality of components in the motor system, wherein the plurality of components include at least two of the following: shielded cable, DC bus capacitor, power module, inverter housing and motor in the motor system; Electromagnetic compatibility (EMC) integration is performed on the equivalent circuit models of the multiple components to obtain the EMC simulation analysis model.

4. The shaft voltage suppression method for a motor system according to claim 3, characterized in that, Obtaining the equivalent circuit model of the shielded cable in the motor system includes: Obtain the dimensional parameters of the shielded cable; Parasitic parameters are extracted from the shielded cable to obtain the parasitic parameters of the shielded cable. The parasitic capacitance of the shielded cable includes at least one of the following: equivalent resistance parameter, capacitance parameter, self-inductance parameter, and mutual inductance parameter. Based on the dimensional parameters and the parasitic parameters of the shielded cable, an equivalent circuit model of the shielded cable is constructed.

5. The shaft voltage suppression method for a motor system according to claim 3, characterized in that, Obtaining the equivalent circuit model of the power module in the motor system includes: The module manual data and double-pulse test data of the power module are obtained, wherein the module manual data is used to represent the product data recorded in the product manual of the power module, and the double-pulse test data is used to represent the test data obtained by performing a pulse test on the power module based on two consecutive pulse signals. Based on the module manual data and the dual-pulse test data, an equivalent circuit model of the power module is constructed.

6. The shaft voltage suppression method for a motor system according to claim 3, characterized in that, Obtaining the equivalent circuit model of the inverter housing in the motor system includes: Obtain a three-dimensional simulation model of the inverter housing; Based on the three-dimensional simulation model, the passive linear component parameters between different metals of the inverter housing and the port parasitic parameters between different ports are determined. The passive linear component parameters include at least one of the following: resistance parameters, inductance parameters, and capacitance parameters. Based on the passive linear element parameters and the port parasitic parameters, an equivalent circuit model of the inverter housing is constructed.

7. The shaft voltage suppression method for a motor system according to claim 1, characterized in that, Based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model, an integrated simulation is performed to obtain the integrated shaft voltage simulation model of the motor system, including: Based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model, an integrated simulation is performed to obtain the initial shaft voltage simulation integrated model; The motor system was tested to obtain the actual shaft voltage parameters of the motor system; Based on the initial shaft voltage simulation integrated model, the motor system was simulated and tested to obtain the simulated shaft voltage parameters; Based on the initial shaft voltage simulation integrated model, the actual shaft voltage parameters, and the simulated shaft voltage parameters, the shaft voltage simulation integrated model is obtained.

8. The shaft voltage suppression method for a motor system according to claim 7, characterized in that, Based on the initial shaft voltage simulation integrated model, the actual shaft voltage parameters, and the simulated shaft voltage parameters, the shaft voltage simulation integrated model is obtained, including: Determine the parameter deviation between the actual axis voltage parameters and the simulated axis voltage parameters; If the parameter deviation is less than the preset deviation, the initial shaft voltage simulation integrated model is determined as the shaft voltage simulation integrated model; If the parameter deviation is greater than or equal to the preset deviation, the model parameters of the initial shaft voltage simulation integrated model are adjusted to obtain the shaft voltage simulation integrated model.

9. A shaft voltage suppression device for a motor system, characterized in that, include: The acquisition module is used to acquire the motor shaft voltage simulation model and electromagnetic compatibility simulation analysis model of the vehicle's motor system. The motor shaft voltage simulation model is used to represent the equivalent circuit model of the parasitic capacitance that generates the shaft voltage in the motor system. The shaft voltage is used to represent the voltage between the bearing and the rotor in the motor system. The electromagnetic compatibility simulation analysis model is used to represent the simulation analysis model obtained by electromagnetic compatibility integration of the equivalent circuit models of multiple components in the motor system. The simulation module is used to perform integrated simulation of the motor system based on the motor shaft voltage simulation model and the electromagnetic compatibility simulation analysis model, so as to obtain the integrated simulation model of the motor system shaft voltage. The filtering module is used to filter multiple shaft voltage suppression strategies in a preset shaft voltage suppression strategy set based on the shaft voltage simulation integrated model to obtain a target shaft voltage suppression strategy, wherein the target shaft voltage suppression strategy is used to guide the shaft voltage suppression of the motor system.

10. An electronic device, characterized in that, include: Memory, which stores executable programs; A processor for running the program, wherein the program, when running, executes the shaft voltage suppression method for the motor system according to any one of claims 1 to 8.

11. 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 shaft voltage suppression method for the motor system according to any one of claims 1 to 8.

12. A computer program product, characterized in that, It includes computer instructions that, when executed by a processor, implement the shaft voltage suppression method for a motor system according to any one of claims 1 to 8.

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