A method and system for motor single-stage noise target formulation based on simulation

Abstract

The application relates to a kind of motor single body order noise target formulation method and system based on simulation, including establishing motor electromagnetic model, obtaining the radial three-dimensional electromagnetic force under the main order of motor;Establishing electric drive assembly finite element model and motor test box assembly finite element model and carrying out modal analysis, obtain the modal shape under each frequency distribution of electric drive assembly and motor test box assembly;Based on modal shape, obtain the surface vibration response result of electric drive assembly and test box assembly surface vibration response result;Vibration response result is used as excitation source to carry out sound radiation analysis, obtain the order noise curve of electric drive assembly and test box assembly order noise curve and line difference, obtain noise difference curve;The existing electric drive assembly order noise target curve is subtracted from noise difference curve, and the motor single body order noise target curve is obtained, the application can formulate reasonable motor single body order noise target in the early stage of electric drive assembly development to shorten development cycle and reduce development cost.

Description

Technical Field

[0001] This invention relates to the field of NVH technology for new energy vehicles, specifically to a simulation-based method and system for setting target noise levels for individual motor units. Background Technology

[0002] As the core of new energy vehicles, the electric drive system assembly's NVH characteristics determine the driver's driving comfort experience. When the vehicle is driving in pure electric mode, the NVH problem caused by the motor's whistling is particularly prominent.

[0003] Motor whistling noise is mainly generated by the alternating electromagnetic force produced by the air gap magnetic field acting on the stator and rotor of the motor, and it exhibits obvious order characteristics. Order refers to the number of times a certain phenomenon occurs during one revolution of rotating machinery or an integer multiple of a reference frequency. The motor order refers to the response of vibration and noise caused by motor rotation. This motor order response is a multiple of the rotational speed or frequency, remaining constant with respect to the rotational speed. The order is independent of the actual rotational speed of the shaft and is a multiple or fraction of the reference shaft speed. The motor order can be calculated by the ratio of the number of pole pairs to the number of slots. Controlling the order noise of individual motors is a crucial step in the early stages of electric drive assembly development, specifically in motor selection and matching. Developing reasonable order noise targets for individual motors based on the overall electric drive assembly's order noise goals can ensure good NVH performance of the electric drive assembly while reducing motor assembly development costs, shortening the development cycle, and ultimately improving the customer's driving experience.

[0004] Patent document CN111933178A discloses a method for setting motor order noise targets based on forward development. This method includes collecting in-vehicle noise data of a target vehicle model to obtain background noise, correcting the rotational speed to obtain the correct relationship between vehicle speed and rotational speed, constructing the main order noise of the motor using scheduling indicators, evaluating and modifying the order noise through filtering and playback, until the order noise meets subjective evaluation requirements, measuring the noise transfer function from the front compartment to the vehicle interior, and dividing the edited motor order noise by the measured transfer function to obtain the target near-field order noise of the motor. However, this application is based on the motor order noise target under the assembled state of the electric drive assembly during whole-vehicle testing, rather than the order noise target of a single motor unit. Therefore, it is not suitable for selecting motor products and developing the NVH (Noise, Vibration, and Harshness) of individual motor units in the early stages of development. Summary of the Invention

[0005] One objective of this invention is to provide a simulation-based method for setting individual motor noise targets, which can set reasonable individual motor noise targets in the early stages of electric drive assembly development to shorten the development cycle and reduce development costs. Another objective is to provide a system for implementing the simulation-based method for setting individual motor noise targets.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A simulation-based method for determining the order noise target of a single motor unit, comprising:

[0008] S1. Establish the electromagnetic model of the motor and calculate the radial two-dimensional electromagnetic force on the stator tooth surface at each speed based on the external characteristic parameters of the motor.

[0009] S2. The radial two-dimensional electromagnetic force on the stator tooth surface is stretched to obtain the three-dimensional electromagnetic force, and the radial three-dimensional electromagnetic force under the main order of the motor is extracted.

[0010] S3. Establish finite element models of the electric drive assembly and the motor test box assembly, and perform modal analysis on the electric drive assembly and the motor test box assembly respectively to obtain the mode shapes of the electric drive assembly and the motor test box assembly under each frequency distribution.

[0011] S4. Map the radial three-dimensional electromagnetic force of the motor under the main order onto the finite element model of the electric drive assembly and the motor test box assembly. Based on the mode shape, perform vibration response analysis of the electric drive assembly and the test box assembly under the order radial electromagnetic excitation, and obtain the surface vibration response results of the electric drive assembly and the surface vibration response results of the test box assembly.

[0012] S5. Using the vibration response results as the excitation source, perform acoustic radiation analysis to obtain the order noise curves of the electric drive assembly and the test box assembly, and then calculate the difference between the two curves to obtain the noise difference curves at each order.

[0013] S6. Calculate the difference between the existing electric drive assembly order noise target curve and the noise difference curve at each order to obtain the motor unit order noise target curve.

[0014] Furthermore, in step S2, the radial two-dimensional electromagnetic force on the stator tooth surface is stretched to obtain a three-dimensional electromagnetic force, including:

[0015] The radial two-dimensional electromagnetic force on the stator tooth surface is extended axially according to the stator stack height to generate a three-dimensional electromagnetic force that fits against the inner surface of the stator.

[0016] The main order of the motor is the electromagnetic force frequency order corresponding to a motor spatial module of 0.

[0017] Furthermore, in S3, the electric drive assembly includes a motor stator, an electric drive assembly housing, and a controller housing, and the motor test box assembly includes a motor stator and a test box housing.

[0018] Furthermore, in S3, establishing a finite element model of the electric drive assembly includes:

[0019] The components of the electric drive assembly are divided into finite element meshes, and the finite element meshes of each component are assigned materials and properties.

[0020] The bolted connection between the motor stator and the electric drive assembly housing is simulated using three rigid elements and two beam elements with the same diameter as the bolts. The bolted connections between the electric drive assembly housings and the controller housing are simulated using rigid elements.

[0021] Add a centralized mass unit and adjust the mass and center of gravity of the electric drive assembly to match the actual design state.

[0022] Furthermore, in step S3, the finite element model of the motor test box is established, including:

[0023] The motor test box components are divided into finite element meshes, and the finite element meshes of each component are assigned material and properties.

[0024] The motor stator and the test box are connected according to the assembly. The bolt connection between the motor stator and the test box is simulated by three rigid elements and two beam elements with the same diameter as the bolts.

[0025] Add a centralized mass unit and adjust the mass and center of gravity of the motor test box assembly to match the actual design state.

[0026] Furthermore, in step S3, modal analysis is performed on the electric drive assembly and the motor test box assembly, including:

[0027] Both the modal analysis of the electric drive assembly and the modal analysis of the motor test box assembly are constrained modal analyses. The constraint of the electric drive assembly model is the bolt connection of the large end flange, and the constraint of the motor test box model is the bolt connection of the flange connecting to the test bench. All bolt connections are defined with full constraints of 6 degrees of freedom.

[0028] Furthermore, in step S5, the vibration response result is used as an excitation source for acoustic radiation analysis, including:

[0029] A cuboid sound field was established 1 meter away from the outermost edge of the electric drive assembly and the motor test box assembly. The radiated noise curves of the top center point, the front center point, and the rear center point were averaged to obtain the order noise curves of the electric drive assembly and the test box assembly.

[0030] Furthermore, in step S5, the order noise curves of the electric drive assembly and the test box assembly are obtained respectively, and the difference between the two curves is calculated to obtain the noise difference curves at each order, including:

[0031] At each frequency point, the order noise of the electric drive assembly is subtracted from the order noise of the test box assembly, and the resulting fluctuating order noise difference curve is fitted to establish a function related to the frequency of the difference noise, so as to obtain a smooth noise difference curve for each order that can reflect the changing trend of the difference curve.

[0032] Furthermore, in S6, the existing electric drive assembly order noise target curve is based on benchmark testing or on the sound insulation and absorption of the whole vehicle and the order background noise of the whole vehicle.

[0033] A system for executing the simulation-based method for determining the order noise target of a single motor unit as described above, comprising:

[0034] The first calculation module is used to establish the electromagnetic model of the motor and obtain the three-dimensional radial electromagnetic force on the stator tooth surface at various speeds of the motor.

[0035] The first analysis module is used to perform finite element analysis on the electric drive assembly and the motor test box assembly. Based on the radial three-dimensional electromagnetic force of the stator tooth surface at various motor speeds, the surface vibration response results of the electric drive assembly and the test box assembly are obtained.

[0036] The second analysis module is used to perform acoustic finite element analysis on the motor. Based on the surface vibration response results of the electric drive assembly and the test box assembly, the order noise curves of the electric drive assembly and the test box assembly are obtained. The difference between the order noise curves of the electric drive assembly and the test box assembly is obtained to obtain the noise difference curves at each order. Finally, the difference between the existing order noise target curve of the electric drive assembly and the noise difference curves at each order is obtained to obtain the order noise target curve of the motor unit.

[0037] The beneficial effects of this invention are:

[0038] 1. By establishing simulation analysis models of the order noise of the electric drive assembly under electromagnetic excitation and the order noise of the test box motor under electromagnetic excitation, the difference between the order sound pressure level of the motor in the electric drive assembly state and the test box state is calculated. This difference represents the noise in the electric drive assembly excluding the individual motor units. This difference is calculated by subtracting the order noise target of the electric drive assembly, and finally the order noise performance target of the individual motor units is obtained. This invention is a target setting method based on forward development, which establishes the correlation between the order noise of the individual motor units and the order noise of the electric drive assembly, and the target setting is more reasonable and accurate.

[0039] 2. Because this invention can set reasonable motor unit noise targets in the early stages of electric drive product development, compared to traditional methods that set motor noise targets based on the electric drive assembly assembly status during later vehicle testing, this invention allows for earlier selection of motor products and NVH development of individual motor units based on their noise targets. It enables rectification and optimization of motor whine issues in the early stages of development, mitigating the risk of substandard motor noise after the electric drive assembly prototype undergoes bench testing and acceptance. This eliminates the difficulty in controlling motor whine noise risks in the later stages of project development. While ensuring good NVH quality of the electric drive assembly, this invention significantly reduces development costs, shortens the development cycle, and improves the NVH quality of the entire vehicle, making it valuable for widespread application in the automotive NVH technology field. Attached Figure Description

[0040] Figure 1 This is a flowchart of a simulation-based method for determining the order noise target of a single motor unit;

[0041] Figure 2 This is a schematic diagram of a simulation-based system for determining the order noise target of a single motor unit.

[0042] Figure 3 This is a schematic diagram of the three-dimensional electromagnetic force distribution;

[0043] Figure 4 This is a schematic diagram illustrating the definition of modal analysis in sound field modeling;

[0044] Figure 5 This is a schematic diagram of the order noise curves of the electric drive assembly and the test box assembly;

[0045] Figure 6 This is a schematic diagram of the fitted noise difference curve;

[0046] Figure 7 This is a schematic diagram of the target noise curve for a single motor unit.

[0047] Markings and technical features in the diagram:

[0048] 1. First calculation module; 2. First analysis module; 3. First analysis module. Detailed Implementation

[0049] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0050] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0051] This embodiment proposes a simulation-based method for setting target order noise for individual motor units, such as... Figures 1-6 As shown, it includes:

[0052] S1. Establish the electromagnetic model of the motor and calculate the radial two-dimensional electromagnetic force on the stator tooth surface at each speed based on the external characteristic parameters of the motor; the electromagnetic model of the motor is the electromagnetic model of the target motor for selection.

[0053] S2. The radial two-dimensional electromagnetic force on the stator tooth surface is stretched to obtain the three-dimensional electromagnetic force, and the radial three-dimensional electromagnetic force under the main order of the motor is extracted.

[0054] In this embodiment, as Figure 3 As shown, the radial two-dimensional electromagnetic force on the stator tooth surface is stretched to obtain a three-dimensional electromagnetic force, including:

[0055] The radial two-dimensional electromagnetic force on the stator tooth surface is extended axially according to the stator stack height to generate a three-dimensional electromagnetic force that fits against the inner surface of the stator.

[0056] The primary order of the motor is the electromagnetic force frequency order corresponding to a spatial module of 0. The electromagnetic force frequency corresponding to a spatial module of 0 refers to the electromagnetic force time frequency corresponding to a breathing waveform in the spatial force wave after performing a spacetime Fourier transform on the electromagnetic force. The electromagnetic force frequency order corresponding to a spatial module of 0 can be calculated from the number of pole pairs and slots of the motor.

[0057] S3. Establish finite element models of the electric drive assembly and the motor test box assembly, and perform modal analysis on the electric drive assembly and the motor test box assembly respectively to obtain the mode shapes of the electric drive assembly and the motor test box assembly under each frequency distribution.

[0058] In this embodiment, the electric drive assembly includes a motor stator, an electric drive assembly housing, and a controller housing, and the motor test box assembly includes a motor stator and a test box housing. The electric drive assembly is obtained by the OEM integrating the electric drive assembly housing and controller onto a motor provided by the motor supplier. The motor test box refers to the motor housing provided by the motor supplier for individual motor bench testing and acceptance.

[0059] In this embodiment, a finite element model of the electric drive assembly is established, including:

[0060] S311. Divide each component of the electric drive assembly into a finite element mesh and assign material and properties to the finite element mesh of each component; wherein the material of the motor stator is an anisotropic material, and the assigned material is the material and properties of the motor stator after modal calibration.

[0061] S312. The bolted connection between the motor stator and the electric drive assembly housing is simulated using three rigid elements and two beam elements with the same diameter as the bolts. The bolted connections between the electric drive assembly housings and the controller housing are simulated using rigid elements.

[0062] S313. Add lumped mass elements to adjust the mass and center of gravity of the electric drive assembly to match the actual design state. Adding lumped mass elements can replace the influence of the motor rotor on the simulation results, thereby simplifying the model and improving modeling efficiency.

[0063] In this embodiment, a finite element model of the motor test box is established, including:

[0064] S321. Divide each component of the motor test box into a finite element mesh and assign material and properties to the finite element mesh of each component.

[0065] S322. The connection between the motor stator and the test box is established according to the assembly. The bolt connection between the motor stator and the test box is simulated by three rigid elements plus two beam elements with the same diameter as the bolts.

[0066] S323. Add lumped mass elements and adjust the mass and center of gravity of the motor test box assembly to match the actual design state. Adding lumped mass elements can replace the influence of the motor rotor on the simulation results, thereby simplifying the model and improving modeling efficiency.

[0067] In this embodiment, modal analysis is performed on the electric drive assembly and the motor test box assembly, including:

[0068] Both the modal analysis of the electric drive assembly and the modal analysis of the motor test box assembly are constrained modal analyses. The constraint of the electric drive assembly model is the bolt connection of the large end flange, and the constraint of the motor test box model is the bolt connection of the flange connecting to the test bench. All bolt connections are defined with full constraints of 6 degrees of freedom.

[0069] S4. Map the radial three-dimensional electromagnetic force of the motor under the main order onto the finite element model of the electric drive assembly and the motor test box assembly. Based on the mode shape, perform vibration response analysis of the electric drive assembly and the test box assembly under the order radial electromagnetic excitation, and obtain the surface vibration response results of the electric drive assembly and the surface vibration response results of the test box assembly.

[0070] S5, such as Figure 5As shown, the vibration response results are used as the excitation source for acoustic radiation analysis. The order noise curves of the electric drive assembly and the test box assembly are obtained respectively. The difference between the two curves is then calculated to obtain the noise difference curves at each order.

[0071] In this embodiment, the vibration response result is used as the excitation source for acoustic radiation analysis, including:

[0072] A rectangular sound field was created using acoustic simulation software at a distance of 1 meter from the outermost edge of the electric drive assembly and motor test box assembly. Figure 4 As shown, the radiated noise curves of the top center point, front center point, and rear center point are averaged to obtain the order noise curves of the electric drive assembly and the test box assembly.

[0073] In this embodiment, as Figure 6 As shown, the order noise curves of the electric drive assembly and the test box assembly were obtained respectively. The difference between the two curves was calculated to obtain the noise difference curves at each order, including:

[0074] At each frequency point, the order noise of the electric drive assembly is subtracted from the order noise of the test box assembly. The resulting fluctuating order noise difference curve is then fitted to establish a function relating the difference noise to the frequency, resulting in smooth difference curves for each order noise level that reflect the trend of the difference curve. The fitting process provides the goodness-of-fit R² value. An R² close to 1 indicates that the trend of the fitted curve is consistent with the difference curve obtained in S8, generating a smooth curve that reflects the trend of the difference curve.

[0075] S6, such as Figure 7 As shown, the difference between the existing electric drive assembly order noise target curve and the noise difference curve at each order is calculated to obtain the motor unit order noise target curve.

[0076] In this embodiment, the existing electric drive assembly order noise target curve is based on benchmarking tests or on the sound insulation and absorption of the whole vehicle and the order background sound of the whole vehicle.

[0077] This embodiment also provides a system for executing the simulation-based method for determining the order noise target of a single motor unit, such as... Figure 2 As shown, it includes:

[0078] The first calculation module 1 is used to establish the electromagnetic model of the motor and obtain the three-dimensional radial electromagnetic force of the stator tooth surface at each speed of the motor.

[0079] The first analysis module 2 is used to perform finite element analysis on the electric drive assembly and the motor test box assembly. Based on the radial three-dimensional electromagnetic force of the stator tooth surface at various motor speeds, the surface vibration response results of the electric drive assembly and the surface vibration response results of the test box assembly are obtained.

[0080] The second analysis module 3 is used to perform acoustic finite element analysis on the motor. Based on the surface vibration response results of the electric drive assembly and the test box assembly, the order noise curves of the electric drive assembly and the test box assembly are obtained. The difference between the order noise curves of the electric drive assembly and the test box assembly is obtained to obtain the noise difference curves at each order. Finally, the difference between the existing order noise target curve of the electric drive assembly and the noise difference curves at each order is obtained to obtain the order noise target curve of the motor unit.

[0081] As can be seen from the detailed description of the above embodiments, the present invention establishes simulation analysis models of the order noise of the electric drive assembly under electromagnetic excitation and the order noise of the test box motor under electromagnetic excitation, respectively, and calculates the difference in the order sound pressure level of the motor under the electric drive assembly state and the test box state. This difference represents the noise in the electric drive assembly excluding the individual motor units. This difference is calculated by subtracting the order noise target of the electric drive assembly, and finally obtaining the order noise performance target of the individual motor units. The present invention is a target setting method based on forward development, which establishes the correlation between the order noise of the individual motor units and the order noise of the electric drive assembly, and the target setting is more reasonable and accurate.

[0082] Furthermore, because this invention can set reasonable motor unit noise targets in the early stages of electric drive product development, compared to traditional methods that set motor noise targets based on the electric drive assembly assembly status during later vehicle testing, it allows for earlier selection of motor products and NVH development of individual motor units based on their noise targets. This enables rectification and optimization of motor whine issues in the early stages of development, mitigating the risk of substandard motor noise after the electric drive assembly prototype undergoes bench testing and acceptance. It also eliminates the difficulty in controlling motor whine noise risks in the later stages of project development. While ensuring good NVH quality of the electric drive assembly, this invention significantly reduces development costs, shortens the development cycle, and improves the NVH quality of the entire vehicle, making it valuable for widespread application in the automotive NVH technology field.

[0083] The above embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention.

Claims

1. A simulation-based method for determining the order noise target of a single motor unit, characterized in that, include: S1. Establish the electromagnetic model of the motor and calculate the radial two-dimensional electromagnetic force on the stator tooth surface at each speed based on the external characteristic parameters of the motor. S2. The radial two-dimensional electromagnetic force on the stator tooth surface is stretched to obtain the three-dimensional electromagnetic force, and the radial three-dimensional electromagnetic force under the main order of the motor is extracted. S3. Establish finite element models of the electric drive assembly and the motor test box assembly, and perform modal analysis on the electric drive assembly and the motor test box assembly respectively to obtain the mode shapes of the electric drive assembly and the motor test box assembly under each frequency distribution. S4. Map the radial three-dimensional electromagnetic force of the motor under the main order onto the finite element model of the electric drive assembly and the motor test box assembly. Based on the mode shape, perform vibration response analysis of the electric drive assembly and the test box assembly under the order radial electromagnetic excitation, and obtain the surface vibration response results of the electric drive assembly and the surface vibration response results of the test box assembly. S5. Using the vibration response results as the excitation source, perform acoustic radiation analysis to obtain the order noise curves of the electric drive assembly and the test box assembly, and then calculate the difference between the two curves to obtain the noise difference curves at each order. S6. Calculate the difference between the existing electric drive assembly order noise target curve and the noise difference curve at each order to obtain the motor unit order noise target curve.

2. The simulation-based method for determining the order noise target of a single motor unit according to claim 1, characterized in that, In step S2, the radial two-dimensional electromagnetic force on the stator tooth surface is stretched to obtain a three-dimensional electromagnetic force, including: The radial two-dimensional electromagnetic force on the stator tooth surface is extended axially according to the stator stack height to generate a three-dimensional electromagnetic force that fits against the inner surface of the stator. The main order of the motor is the electromagnetic force frequency order corresponding to a motor spatial module of 0.

3. The simulation-based method for determining the order noise target of a single motor unit according to claim 1, characterized in that, In S3, the electric drive assembly includes a motor stator, an electric drive assembly housing, and a controller housing, and the motor test box assembly includes a motor stator and a test box housing.

4. The simulation-based method for determining the order noise target of a single motor unit according to claim 3, characterized in that, In S3, a finite element model of the electric drive assembly is established, including: The components of the electric drive assembly are divided into finite element meshes, and the finite element meshes of each component are assigned materials and properties. The bolted connection between the motor stator and the electric drive assembly housing is simulated using three rigid elements and two beam elements with the same diameter as the bolts. The bolted connections between the electric drive assembly housings and the controller housing are simulated using rigid elements. Add a centralized mass unit and adjust the mass and center of gravity of the electric drive assembly to match the actual design state.

5. The simulation-based method for determining the order noise target of a single motor unit according to claim 3, characterized in that, In S3, a finite element model of the motor test box is established, including: The motor test box components are divided into finite element meshes, and the finite element meshes of each component are assigned material and properties. The motor stator and the test box are connected according to the assembly. The bolt connection between the motor stator and the test box is simulated by three rigid elements and two beam elements with the same diameter as the bolts. Add a centralized mass unit and adjust the mass and center of gravity of the motor test box assembly to match the actual design state.

6. The simulation-based method for determining the order noise target of a single motor unit according to claim 1, characterized in that, In step S3, modal analysis is performed on the electric drive assembly and the motor test box assembly, including: Both the modal analysis of the electric drive assembly and the modal analysis of the motor test box assembly are constrained modal analyses. The constraint of the electric drive assembly model is the bolt connection of the large end flange, and the constraint of the motor test box model is the bolt connection of the flange connecting to the test bench. All bolt connections are defined with full constraints of 6 degrees of freedom.

7. The simulation-based method for determining the order noise target of a single motor unit according to claim 1, characterized in that, In step S5, the vibration response result is used as the excitation source for acoustic radiation analysis, including: A cuboid sound field was established 1 meter away from the outermost edge of the electric drive assembly and the motor test box assembly. The radiated noise curves of the top center point, the front center point, and the rear center point were averaged to obtain the order noise curves of the electric drive assembly and the test box assembly.

8. The simulation-based method for determining the order noise target of a single motor unit according to claim 1, characterized in that, In step S5, the order noise curves of the electric drive assembly and the test box assembly are obtained respectively, and the difference between the two curves is calculated to obtain the noise difference curves at each order, including: At each frequency point, the order noise of the electric drive assembly is subtracted from the order noise of the test box assembly, and the resulting fluctuating order noise difference curve is fitted to establish a function related to the frequency of the difference noise, so as to obtain a smooth noise difference curve for each order that can reflect the changing trend of the difference curve.

9. The simulation-based method for determining the order noise target of a single motor unit according to claim 1, characterized in that, In S6, the existing electric drive assembly order noise target curve is based on benchmark testing or on the sound insulation and absorption of the whole vehicle and the order background sound of the whole vehicle.

10. A system for executing the simulation-based method for determining the order noise target of a single motor unit according to any one of claims 1-9, characterized in that, include: The first calculation module is used to establish the electromagnetic model of the motor and obtain the three-dimensional radial electromagnetic force on the stator tooth surface at various speeds of the motor. The first analysis module is used to perform finite element analysis on the electric drive assembly and the motor test box assembly. Based on the radial three-dimensional electromagnetic force of the stator tooth surface at various motor speeds, the surface vibration response results of the electric drive assembly and the test box assembly are obtained. The second analysis module is used to perform acoustic finite element analysis on the motor. Based on the surface vibration response results of the electric drive assembly and the test box assembly, the order noise curves of the electric drive assembly and the test box assembly are obtained. The difference between the order noise curves of the electric drive assembly and the test box assembly is obtained to obtain the noise difference curves at each order. Finally, the difference between the existing order noise target curve of the electric drive assembly and the noise difference curves at each order is obtained to obtain the order noise target curve of the motor unit.

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