Noise optimization method and device for motor rotor, equipment and storage medium

Abstract

The invention discloses a noise optimization method and device for a motor rotor, equipment and a storage medium, and relates to the technical field of driving motors, and the method comprises the steps: determining the sine of the air gap flux density according to the analysis relation between the low noise of the motor rotor and the flux density; building an analytic relationship between the air gap length and the magnetomotive force through the sinusoidal property of the air gap flux density; the motor rotor is optimized according to the air gap industrialization requirement through the analytic relationship between the air gap length and the magnetomotive force to obtain a low-noise rotor structure so as to optimize the noise of the motor rotor. According to the invention, the sinusoidal property of the air gap flux density is determined as a key path through the analytic relationship between the low noise and the flux density of the motor rotor, so that the air gap length and the magnetomotive force of the motor rotor are reasonably matched, and the low-noise rotor structure is obtained through optimization. According to the motor rotor, the situation that noise is high due to the fact that a traditional motor rotor generates large vibration in the operation process is avoided, the vibration noise of the motor is reduced, and the user experience is improved.

Description

Technical Field

[0001] The present application relates to the technical field of drive motors, and in particular to a noise optimization method, device, equipment and storage medium for a motor rotor. Background Art

[0002] For users, the sound feedback during driving is one of the factors that has the greatest impact on the overall driving experience. Positive sound feedback, such as the startup sound, the sound of acceleration, and the deceleration prompt sound, can clearly tell users the status of the car, letting users know clearly that the car has indeed generated feedback on their operations. However, abnormal sounds generated by the car, especially the high-frequency noise of the motor, will cause strong discomfort to users.

[0003] Among them, the noise generated by the motor when working is the superposition of pneumatic noise, electromagnetic noise and mechanical noise. The traditional motor rotor will produce large vibrations during operation, resulting in higher noise, which seriously affects the user experience. Summary of the invention

[0004] The main purpose of this application is to provide a noise optimization method, device, equipment and storage medium for a motor rotor, aiming to solve the technical problem that a traditional motor rotor will generate large vibrations during operation, resulting in high noise, which seriously affects the user experience.

[0005] To achieve the above objectives, the present application proposes a method for optimizing the noise of a motor rotor, the method comprising:

[0006] According to the analytical relationship between the low noise of the motor rotor and the magnetic flux density, the sinusoidal nature of the air gap magnetic flux density is determined;

[0007] By using the sinusoidal property of the air gap magnetic flux density, an analytical relationship between the air gap length and the magnetomotive force is constructed;

[0008] By means of the analytical relationship between the air gap length and the magnetomotive force, the motor rotor is optimized according to the industrial requirements of the air gap to obtain a low-noise rotor structure, thereby optimizing the noise of the motor rotor.

[0009] In one embodiment, the step of determining the sinusoidality of the air gap magnetic flux density according to the analytical relationship between the low noise and magnetic flux density of the motor rotor comprises:

[0010] According to the radial electromagnetic force density, the non-zero-order spatial force wave stator displacement of the motor rotor is determined;

[0011] By means of the non-zero-order spatial force wave stator displacement, an analytical relationship between low noise and magnetic flux density is constructed;

[0012] According to the analytical relationship between the low noise and the magnetic flux density, the sinusoidality of the air gap magnetic flux density of the motor rotor is determined.

[0013] In one embodiment, the step of constructing an analytical relationship between air gap length and magnetomotive force by using the sinusoidality of the air gap magnetic flux density comprises:

[0014] Determining an analytical relationship for the total air gap magnetomotive force of the motor rotor when under load;

[0015] When the requirement of the sinusoidality of the air gap magnetic flux density is met, an analytical relationship between the air gap length and the magnetomotive force is constructed according to the analytical relationship of the total air gap magnetomotive force.

[0016] In one embodiment, the step of constructing an analytical relationship between air gap length and magnetomotive force according to the analytical relationship of the total air gap magnetomotive force comprises:

[0017] Determine the expression relationship between the air gap magnetomotive force and the air gap magnetic flux density according to the analytical relationship of the air gap magnetomotive force;

[0018] The air gap length that does not change with the electrical angle is designed to be an air gap length value that changes with the electrical angle, and based on the expression relationship between the air gap magnetomotive force and the air gap magnetic flux density, the sinusoidal property of the air gap magnetic flux density is obtained;

[0019] According to the sinusoidality of the air gap magnetic flux density, an analytical relationship between the change of the air gap length value and the electrical angle is determined.

[0020] In one embodiment, after the step of determining the analytical relationship between the air gap length value and the electrical angle according to the sinusoidality of the air gap magnetic flux density, the method further includes:

[0021] According to the ratio of the magnetomotive force of the armature winding of the motor rotor to the magnetomotive force generated by the permanent magnet, the analytical relationship between the change of the air gap length value with the electrical angle is simplified to obtain a simplified relationship between the change of the air gap length value with the electrical angle;

[0022] Accordingly, the step of optimizing the motor rotor according to the air gap industrialization requirements through the analytical relationship between the air gap length and the magnetomotive force to obtain a low-noise rotor structure includes:

[0023] According to the requirements of air gap industrialization, the motor rotor is optimized through the simplified relationship between the air gap length value and the electrical angle, so as to obtain a low-noise rotor structure.

[0024] In one embodiment, the step of optimizing the motor rotor according to the industrial requirements of the air gap through the simplified relationship between the air gap length value and the electrical angle to obtain a low-noise rotor structure includes:

[0025] According to the requirements of air gap industrialization, the air gap compensation value of the motor rotor under load is determined through the simplified relationship between the air gap length value and the electrical angle;

[0026] Determine the stator-rotor air gap by asymmetrically cutting the original rotor structure and the air gap compensation value;

[0027] Based on the stator-rotor air gap, a low-noise rotor structure is obtained.

[0028] In addition, to achieve the above-mentioned purpose, the present application also proposes a noise optimization device for a motor rotor, the device comprising:

[0029] The sinusoidal module is used to determine the sinusoidal nature of the air gap flux density based on the analytical relationship between the low noise and flux density of the motor rotor;

[0030] An air gap length module, used to construct an analytical relationship between air gap length and magnetomotive force through the sinusoidal nature of the air gap magnetic flux density;

[0031] The rotor optimization module is used to optimize the motor rotor according to the air gap industrialization requirements through the analytical relationship between the air gap length and the magnetomotive force, so as to obtain a low-noise rotor structure.

[0032] In addition, to achieve the above-mentioned purpose, the present application also proposes a noise optimization device for a motor rotor, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the noise optimization method for a motor rotor as described above.

[0033] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the noise optimization method of the motor rotor as described above are implemented.

[0034] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, the steps of the noise optimization method of the motor rotor as described above are implemented.

[0035] One or more technical solutions proposed in this application have at least the following technical effects: This application first determines the sinusoidal nature of the air gap magnetic density based on the analytical relationship between the low noise and magnetic density of the motor rotor; then, through the sinusoidal nature of the air gap magnetic density, the analytical relationship between the air gap length and the magnetomotive force is constructed; finally, through the analytical relationship between the air gap length and the magnetomotive force, the motor rotor is optimized according to the requirements of air gap industrialization to obtain a low-noise rotor structure to optimize the noise of the motor rotor. Since this application determines the sinusoidal nature of the air gap magnetic density as the key path through the analytical relationship between the low noise and magnetic density of the motor rotor, the air gap length and the magnetomotive force of the motor rotor are reasonably matched to optimize the low-noise rotor structure, which avoids the situation in which the traditional motor rotor will generate large vibrations during operation, resulting in high noise, thereby reducing the motor vibration noise and improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0037] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0038] Figure 1 A schematic diagram of a flow chart provided for Embodiment 1 of the method for optimizing noise of a motor rotor of the present application;

[0039] Figure 2 A schematic diagram of the optimization analysis ideas and implementation process provided in Example 1;

[0040] Figure 3 A schematic diagram of a flow chart provided for Embodiment 2 of the method for optimizing noise of a motor rotor of the present application;

[0041] Figure 4 A schematic diagram of the waveforms of the magnetic potential generated by the winding, the magnetic potential generated by the rotor and the total air gap magnetomotive force when loaded provided in the second embodiment;

[0042] Figure 5 A schematic diagram of the results of optimizing the air gap length through the rotor when under load provided in the second embodiment;

[0043] Figure 6 This is a schematic diagram of the module structure of the noise optimization device for the motor rotor according to an embodiment of the present application;

[0044] Figure 7Schematic diagram of the equipment structure of the hardware operating environment involved in the noise optimization method of the motor rotor in the embodiment of the present application.

[0045] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0046] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0047] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0048] It should be noted that the execution subject of this embodiment can be a computing service device with data processing and rotor structure optimization functions, such as a personal computer, a server, etc., or an electronic device capable of realizing the above functions, a noise optimization device for a motor rotor that executes the noise optimization method for a motor rotor of this application (hereinafter referred to as an optimization device), etc., and this embodiment does not limit this. The following takes the optimization device as an example to illustrate this embodiment and the following embodiments.

[0049] Based on this, the embodiment of the present application provides a noise optimization method for a motor rotor, referring to Figure 1 , Figure 1 A schematic diagram of a flow chart of a first embodiment of a method for optimizing noise of a motor rotor according to the present application.

[0050] In this embodiment, the noise optimization method of the motor rotor includes steps S10 to S30:

[0051] Step S10: Determine the sinusoidality of the air gap magnetic flux according to the analytical relationship between the low noise of the motor rotor and the magnetic flux.

[0052] It should be noted that there is a certain correlation and mutual influence between the noise of the motor rotor and the magnetic flux density (such as radial electromagnetic force density and air gap magnetic flux density). The distribution and change of magnetic flux density will affect the electromagnetic force when the motor is running, and the fluctuation of these electromagnetic forces may cause the vibration displacement of the motor rotor, thereby generating noise.

[0053] When the distribution of magnetic flux density is more reasonable and uniform, and the change of magnetic flux density is relatively stable, the electromagnetic force fluctuation is smaller, which helps to reduce the noise during motor operation. Therefore, optimization design based on the correlation and mutual influence between noise and magnetic flux density (i.e., analytical relationship) can better achieve the low-noise performance of the motor rotor.

[0054] It should be noted that the sinusoidal nature of the air gap magnetic flux density is the characteristic that the change pattern of the magnetic flux density in the air gap of the motor is close to a sine wave.

[0055] Ideally, the sinusoidal distribution of the air gap flux density of the motor can make the motor run more smoothly and reduce adverse effects such as torque pulsation and vibration noise. If the air gap flux density deviates greatly from the sinusoidal property, it may cause the motor performance to deteriorate, such as generating large harmonics, reducing efficiency, and increasing noise. Therefore, the motor rotor structure can be optimized by maintaining a good sinusoidal property of the air gap flux density as the key path.

[0056] Step S20: constructing an analytical relationship between the air gap length and the magnetomotive force through the sinusoidal property of the air gap magnetic flux density.

[0057] It should be noted that the air gap is the gap between the stator and the rotor in the motor, and the air gap length is the size of this gap.

[0058] Magnetomotive force is the force of magnetic flux generated in the magnetic circuit of the motor. The size and distribution of magnetomotive force will affect the strength and distribution of the magnetic field. Magnetomotive force can include magnetomotive force generated by the rotor permanent magnet and air gap magnetomotive force generated by the armature winding.

[0059] There is a certain correlation (i.e., analytical relationship) between the air gap length and the magnetomotive force. The change of the air gap length will affect the magnetic resistance of the magnetic circuit, and thus affect the relationship between the magnetomotive force and the magnetic flux. When the magnetomotive force is constant, the change of the air gap length will lead to the change of the magnetic flux density in the air gap; conversely, to obtain the required magnetic flux density at a certain air gap length, the corresponding magnetomotive force is required. This quantitative relationship and change law between them is their analytical relationship.

[0060] Step S30: optimizing the motor rotor according to the air gap industrialization requirements through the analytical relationship between the air gap length and the magnetomotive force, and obtaining a low-noise rotor structure to optimize the noise of the motor rotor.

[0061] It should be noted that the air gap industrialization requirements are standard requirements that must be met for air gap-related designs in motor rotors in industrial production environments, for example, they may include precise control requirements for air gap length, uniformity and other parameters.

[0062] It should be noted that the low-noise rotor structure is designed to reduce the noise generated during operation. That is, according to the requirements of air gap industrialization, under the premise of considering the design tolerance and manufacturing stability, the sinusoidal nature of the motor air gap magnetic flux density can be ensured through the analytical relationship between the air gap length and the magnetomotive force, thereby designing a motor rotor with low vibration noise, so that the rotor can effectively reduce the generation and propagation of noise during operation.

[0063] In this embodiment, firstly, according to the analytical relationship between the low noise and magnetic flux density of the motor rotor, the sinusoidal nature of the air gap magnetic flux density can be determined as the key path of the rotor design, because the sinusoidal distribution of the air gap magnetic flux density of the motor can make the motor run more smoothly and reduce the adverse effects such as torque pulsation and vibration noise. Then, the analytical relationship between the air gap length and the magnetomotive force when the sinusoidal requirements of the air gap magnetic flux density are met is established, that is, by reasonably matching the air gap magnetomotive force and the air gap length under the load condition, the analytical result of the air gap that meets the low noise rotor can be determined. Finally, the industrialization requirements of the air gap are further clarified, and the motor rotor is optimized according to the analytical results of the air gap to obtain a low noise rotor structure to reduce the noise of the motor rotor. Therefore, under the premise of considering the design tolerance and manufacturing stability, the sinusoidal nature of the motor air gap magnetic flux density is guaranteed by the above analytical relationship, thereby ensuring the low vibration noise of the motor rotor.

[0064] For easier understanding, please refer to Figure 2 , Figure 2 The following is a flow chart of the optimization analysis ideas and implementation process provided in Example 1. The noise optimization of the motor rotor structure is divided into three steps:

[0065] Step 1, first of all, is to establish an analytical relationship between noise and magnetic flux density, which can determine that the sinusoidal nature of the air gap magnetic flux density is the key path for rotor design. The key to designing a low-noise rotor is the low vibration displacement of the rotor, and the low vibration displacement of the rotor requires low electromagnetic force, which is determined by low spatial force wave number and low harmonic electromagnetic force. Therefore, by inverse reasoning, it can be seen that noise and magnetic flux density are interrelated and influence each other, and thus it can be seen that the sinusoidal nature of the air gap magnetic flux density is the key path for low-noise rotor design.

[0066] Step 2, then, based on the sinusoidality of the air gap magnetic density, establish an analytical relationship between the air gap length and the magnetomotive force when the sinusoidality requirement of the air gap magnetic density is met. The sinusoidal distribution of the air gap magnetic density can make the motor run more smoothly and reduce adverse effects such as torque pulsation and vibration noise. Therefore, the higher the sinusoidality of the air gap magnetic density, the smaller the rotor noise. The air gap magnetic density is determined by the air gap length and the magnetomotive force. Therefore, the calculation results of the air gap magnetomotive force can be used to reasonably match the air gap magnetomotive force and the air gap length of the load condition to determine the analytical results of the air gap.

[0067] Step 3, finally further clarify the industrial analytical requirements of the air gap, optimize the rotor according to the requirements, and obtain a low-noise rotor structure to reduce the noise of the motor rotor.

[0068] This embodiment provides a noise optimization of a motor rotor. First, according to the analytical relationship between the low noise and magnetic flux density of the motor rotor, the sinusoidal nature of the air gap magnetic flux density can be determined as the key path of the rotor design, because the sinusoidal distribution of the air gap magnetic flux density of the motor can make the motor run more smoothly and reduce the adverse effects such as torque pulsation and vibration noise. Then, the analytical relationship between the air gap length and the magnetomotive force when the sinusoidal requirements of the air gap magnetic flux density are met is established, that is, by reasonably matching the air gap magnetomotive force and the air gap length of the load condition, the analytical result of the air gap that meets the low-noise rotor can be determined. Finally, the industrialization requirements of the air gap are further clarified, and the motor rotor is optimized according to the analytical results of the air gap to obtain the low-noise rotor structure data to reduce the noise of the motor rotor. Since this embodiment determines the sinusoidal nature of the air gap magnetic flux density as the key path through the analytical relationship between the low noise and magnetic flux density of the motor rotor, the air gap length and the magnetomotive force of the motor rotor are reasonably matched to optimize the low-noise rotor structure, avoiding the situation that the traditional motor rotor will generate large vibrations during operation, resulting in high noise, thereby reducing the vibration noise of the motor and improving the user experience.

[0069] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be repeated in the following. Figure 1 and Figure 3 , Figure 3 A schematic diagram of the flow chart provided for Embodiment 2 of the method for optimizing noise of a motor rotor of the present application.

[0070] In this example, step S10 includes steps S11 to S13:

[0071] Step S11: Determine the non-zero-order spatial force wave stator displacement of the motor rotor according to the radial electromagnetic force density.

[0072] It should be noted that the radial electromagnetic force density is the magnitude of the electromagnetic force per unit volume in the radial direction of the motor. When the motor is running, the electromagnetic field between the stator and the rotor will generate electromagnetic force, among which the radial electromagnetic force has an important influence on the vibration and noise of the motor.

[0073] It should be noted that non-zero-order spatial force waves are force waves with specific spatial distribution patterns in the motor except for the fundamental wave (zero-order). Stator displacement refers to the position change of the stator part of the motor under the action of these non-zero-order spatial force waves.

[0074] Non-zero-order spatial force waves may cause the stator to move slightly or vibrate in a certain direction, which may cause noise, increase vibration, or affect the stability of the motor.

[0075] Step S12: constructing an analytical relationship between low noise and magnetic flux density through the non-zero-order spatial force wave stator displacement.

[0076] Step S13: Determine the sinusoidality of the air gap magnetic flux of the motor rotor according to the analytical relationship between the low noise and the magnetic flux.

[0077] In this embodiment, for ease of understanding, an analytical relationship between low noise and magnetic flux density is established, and the analysis process of determining the sinusoidality of air gap magnetic flux density as the key path is as follows:

[0078] According to the Maxwell tensor, the radial electromagnetic force density p can be constructed r The expression is:

[0079]

[0080] Among them, B r Indicates radial air gap flux density, B t Indicates the tangential air gap flux density, μ 0 is the magnetic permeability of vacuum.

[0081] Since the relative magnetic permeability of the magnetic steel is much greater than the air gap magnetic permeability, the tangential magnetic flux density B can be ignored. t , so formula (1) can be further expressed as:

[0082]

[0083] Among them, radial air gap magnetic flux B r It can be expressed as a function of the magnetomotive force f and the magnetic permeance Λ, both of which are functions of time t and space (electrical angle) θ:

[0084] B r (θ,t)=f g (θ,t).Λ(θ,t)(3)

[0085] The total magnetomotive force f in formula (3) is g (θ, t) also includes the magnetomotive force f generated by the permanent magnet pm and the magnetomotive force f generated by the winding arm Two parts:

[0086] f(θ,t)=f arm (θ,t)+f pm (θ,t)(4)

[0087] The radial electromagnetic force F of a single stator tooth r It can be expressed as:

[0088] F r =p r A s =p r r g θ s L stk (5)

[0089] Where As is the area of ​​the stator tooth, r g is the radius of the air gap, θ s is the electrical angle of the stator teeth, L stk is the stack length;

[0090] Instead of the zero-order subspace force wave stator displacement d m≠0 for:

[0091]

[0092] Where R i is the inner diameter of the stator teeth, E is the elastic modulus of the stator material, R y is the average inner diameter of the gear yoke, T y is the stator thickness, M M≠0 is a non-zero order spatial force wave, M is the force wave order, m is a natural number, and d is the stator tooth yoke displacement.

[0093] In M M≠0 The maximum displacement d of the stator yoke under the action of the order force wave max It can be expressed as:

[0094]

[0095] From formula (7), it can be seen that the vibration displacement of the motor is inversely proportional to the fourth power of the electromagnetic force wave. Reducing vibration requires improving the electromagnetic force of low spatial order, and the sinusoidal performance of the air gap magnetic density effectively ensures that the low-order spatial force wave is as small as possible. At the same time, the low spatial force wave can also improve the high-order harmonics and improve the efficiency to a certain extent. Therefore, the sinusoidal nature of the air gap magnetic density is the key path for low-noise motors.

[0096] In a feasible implementation, step S20 of this embodiment may include the steps of: determining the analytical relationship of the total air gap magnetomotive force of the motor rotor when it is loaded; and constructing an analytical relationship between the air gap length and the magnetomotive force based on the analytical relationship of the total air gap magnetomotive force when the sinusoidal requirement of the air gap magnetic density is met.

[0097] It should be noted that the total air-gap magnetomotive force is the sum of the magnetomotive force generated by the rotor current and acting on the air-gap space when the motor is running under load. The total air-gap magnetomotive force can be composed of the magnetomotive force generated by the rotor permanent magnet and the air-gap magnetomotive force generated by the armature winding.

[0098] Specifically, in a feasible implementation manner, the step of constructing an analytical relationship between air gap length and magnetomotive force according to the analytical relationship of the total air gap magnetomotive force described in this embodiment includes: determining the representation relationship between air gap magnetomotive force and air gap magnetic flux density according to the analytical relationship of the air gap magnetomotive force; designing the air gap length that does not change with the electrical angle to be an air gap length value that changes with the electrical angle, and obtaining the sinusoidal of the air gap magnetic flux density based on the representation relationship between the air gap magnetomotive force and the air gap magnetic flux density; and determining the analytical relationship between the change of air gap length value with the electrical angle according to the sinusoidal of the air gap magnetic flux density.

[0099] It should be noted that there is a certain relationship between the air gap magnetic flux and the air gap magnetomotive force (F). Simply put, the air gap magnetomotive force can be regarded as the "source" of the air gap magnetic flux. According to Ampere's circuit law, the air gap magnetomotive force determines the magnetic field intensity distribution in the air gap to a certain extent, and the air gap magnetic flux is a description of this magnetic field intensity.

[0100] In this embodiment, for ease of understanding, the analysis process of determining the analytical relationship of the total air gap magnetomotive force of the motor rotor when loaded is as follows:

[0101] The total air gap magnetomotive force under load can be expressed as:

[0102] f g =f pn -f arm sin(θ+β) (8)

[0103] Among them, f pm is the magnetomotive force generated by the rotor permanent magnet, f arm is the air gap magnetomotive force generated by the armature winding, where θ is the electrical angle and β is the current angle.

[0104] refer to Figure 4 , Figure 4 The schematic diagram of the magnetic potential generated by the winding, the magnetic potential generated by the rotor and the total air gap magnetic potential waveform under load provided in the second embodiment. The horizontal axis represents the electrical angle θ, ranging from -90 to 270 degrees, and the vertical axis represents the magnetic potential, ranging from -0.4 to 0.4. The rotor magnetic potential f generated by the rotor permanent magnet shown in the figure pm It presents a rectangular distribution. The winding magnetomotive force only considers the fundamental wave component that produces torque, which is a sinusoidal distribution. When loaded, the air gap synthesizes the total magnetomotive force f g It is the result of the coupling between the two. In the figure, the electrical angle of 0° corresponds to the direct axis (i.e., the d-axis), and the electrical angle of ±90° corresponds to the quadrature axis (i.e., the q-axis).

[0105] Further arm and f pm It can be obtained through formula (9) and formula (10) respectively:

[0106] f pmIt can be calculated by Ampere's law:

[0107]

[0108] Where B g_pm is the remanence of the permanent magnet, A pm is the cross-sectional area of ​​the permanent magnet, l pm is the thickness of the permanent magnet, l g is the air gap length, A g is the cross-sectional area of ​​the air gap, μ rec is the magnetic permeability of the permanent magnet.

[0109] f arm It can be expressed as:

[0110]

[0111] Among them, k w is the winding coefficient, I rms is the effective value of current, N ph is the number of series turns per phase, and p is the number of pole pairs.

[0112] Furthermore, the analytical process of constructing the analytical relationship between the air gap length and the magnetomotive force according to the analytical relationship of the total air gap magnetomotive force is specifically as follows:

[0113] Formula (8) Air gap magnetomotive force f g and air gap magnetic flux B g The relationship can be expressed as:

[0114]

[0115] In formula (11), l g is the air gap length, and equation (11) expresses the air gap magnetic flux density B g With air gap l g The analytical relationship of B g The sinusoidal nature of g match Figure 4 The composite magnetomotive force f in the air gap g To guarantee.

[0116] Specifically, B g The sinusoidal nature of g_max Cosine distribution means B g =B g_max cosθ, the air gap value l that does not change with the electrical angle g The value l is designed to change with the electrical angle θ g (θ), for example, in the range of -90°<θ<90°, B g The sinusoidal property of can be guaranteed by equation (12):

[0117]

[0118] Among them B g_max is the amplitude of the sinusoidal distribution of the air gap magnetic flux, that is, B g_max For B g The maximum amplitude of

[0119] And l g The change of (θ) with the electrical angle θ can be expressed as:

[0120]

[0121] In another feasible implementation manner, after the step of determining the analytical relationship of the air gap length value changing with the electrical angle according to the sinusoidality of the air gap magnetic flux in this embodiment, it also includes: simplifying the analytical relationship of the air gap length value changing with the electrical angle according to the ratio of the magnetomotive force of the armature winding of the motor rotor to the magnetomotive force generated by the permanent magnet, and obtaining a simplified relationship of the air gap length value changing with the electrical angle;

[0122] Correspondingly, the step S30 includes: according to the industrial requirements of the air gap, optimizing the motor rotor through the simplified relationship between the air gap length value and the electrical angle, so as to obtain a low-noise rotor structure.

[0123] It should be noted that the magnetomotive force ratio is the ratio of the air gap magnetomotive force generated by the armature winding to the magnetomotive force generated by the rotor permanent magnet.

[0124] In this embodiment, for ease of understanding, the analysis process of the air gap length analytical relationship is further simplified as follows:

[0125] When there is no load, B g Symmetrical about the d axis, it is cosine distributed, so B g_max The air gap at corresponds to the air gap length of the d-axis, that is:

[0126]

[0127] The proportionality factor is defined represents the ratio of the armature winding magnetomotive force to the magnetomotive force generated by the permanent magnet. Equation (13) can be simplified as:

[0128]

[0129] In the formula, k ar, It can be obtained from equations (9) and (10) that the current angle range is -90°<θ<90°, and the current angle β is determined by the load. d is the d-axis air gap length when the rotor is not optimized. Therefore, the rotor can be designed and manufactured according to formula (15) to obtain a high sinusoidal air gap flux density B gThe sinusoidal performance of the air gap magnetic density ensures that the low-order spatial force waves are as small as possible, while also improving high-order harmonics, thereby obtaining a low-noise rotor.

[0130] In another feasible implementation manner, the present embodiment optimizes the motor rotor according to the industrial requirements of the air gap through the simplified relationship between the air gap length value and the electrical angle to obtain the step of obtaining a low-noise rotor structure, including: determining the air gap compensation value of the motor rotor under load according to the industrial requirements of the air gap through the simplified relationship between the air gap length value and the electrical angle; determining the stator-rotor air gap through asymmetric cutting of the original rotor structure and the air gap compensation value; and obtaining a low-noise rotor structure based on the stator-rotor air gap.

[0131] It should be noted that the air gap compensation value is a correction introduced to compensate for the change in the air gap magnetic field caused by load changes. When the motor is loaded, the magnetic field distribution in the air gap will be affected and change to a certain extent, and some unevenness or deviation from the ideal state may occur. The air gap compensation value is used to adjust and compensate for these changes, so as to keep the motor in a good performance and operating state under load.

[0132] It should be noted that the asymmetric cutting of the original rotor structure is to perform an asymmetric cutting process on the original rotor structure in the motor.

[0133] In this embodiment, for ease of understanding, the analysis process of optimizing the rotor according to the air gap industrialization requirements is as follows:

[0134] Figure 4 The solid grey line is the air gap value l between the stator and rotor before the optimized design. normal , its value is a constant, and the radial air gap value remains unchanged at different circumferential angles. After optimizing the rotor, you can refer to Figure 5 , Figure 5 This is a schematic diagram of the results of optimizing the air gap length through the rotor under load provided in Example 2, wherein the horizontal axis represents the electrical angle, ranging from -90 to 90 degrees, and the vertical axis represents the air gap length, ranging from 0 to 1.4. According to formula (15), the rotor design is optimized by the method of this application. When there is no load, the air gap value obtained by the method of this application is correspond Figure 5 The solid grey line in the g_noload ), its distribution is still symmetrical about the d axis, and l can be obtained by symmetrical cutting of the rotor. g (θ). Under load, due to f arm Due to the influence of the current angle β, the symmetry of the air gap between the stator and the rotor about the d-axis is destroyed. The air gap length is calculated using formula (15) as follows: Figure 5 The black dashed line (i.e. g_onload ), the minimum value of the air gap lg_min will be smaller than l normal , the maximum value of the air gap l g_max will be greater than l normal , too small an air gap value is not conducive to dimensional tolerance and manufacturing stability. In order to ensure l g_min With l normal It is necessary to compensate a certain air gap δ, so that the air gap length l g The analytical relationship between (θ) and θ can be expressed as:

[0135]

[0136] Corresponds to Figure 5 The black solid line in the figure, where the air gap compensation value δ is the l calculated in formula (15) g_min With l normal The difference is obtained by asymmetric cutting of the original rotor structure: Figure 5 The stator and rotor air gap is shown in the solid black line, thus obtaining a low-noise rotor structure.

[0137] This embodiment can obtain a sinusoidally distributed air gap magnetic flux under load conditions by reasonably matching the air gap length under load conditions and the total load magnetomotive force. The rotor structure with optimized air gap length not only reduces the vibration noise of the motor, but also improves the motor efficiency to a certain extent.

[0138] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the noise optimization method of the motor rotor of the present application. More simple transformations based on this technical concept are all within the scope of protection of the present application.

[0139] This application also provides a noise optimization device for a motor rotor, please refer to Figure 6 , Figure 6 This is a schematic diagram of the module structure of the noise optimization device for the motor rotor of the embodiment of the present application; the noise optimization device for the motor rotor includes:

[0140] The sinusoidal module 601 is used to determine the sinusoidal property of the air gap magnetic flux density according to the analytical relationship between the low noise and magnetic flux density of the motor rotor;

[0141] An air gap length module 602, used to construct an analytical relationship between air gap length and magnetomotive force through the sinusoidal property of the air gap magnetic flux density;

[0142] The rotor optimization module 603 is used to optimize the motor rotor according to the air gap industrialization requirements through the analytical relationship between the air gap length and the magnetomotive force, so as to obtain a low-noise rotor structure.

[0143] In this embodiment, the sinusoidal module 601 is also used to determine the non-zero-order spatial force wave stator displacement of the motor rotor based on the radial electromagnetic force density; construct an analytical relationship between low noise and magnetic flux density through the non-zero-order spatial force wave stator displacement; and determine the sinusoidal of the air gap magnetic flux density of the motor rotor based on the analytical relationship between low noise and magnetic flux density.

[0144] Furthermore, the air gap length module 602 is also used to determine the analytical relationship of the total air gap magnetomotive force of the motor rotor when it is loaded; when the sinusoidal requirement of the air gap magnetic density is met, the analytical relationship between the air gap length and the magnetomotive force is constructed according to the analytical relationship of the total air gap magnetomotive force.

[0145] Furthermore, the air gap length module 602 is also used to determine the representation relationship between the air gap magnetomotive force and the air gap magnetic density based on the analytical relationship of the air gap magnetomotive force; design the air gap length that does not change with the electrical angle as an air gap length value that changes with the electrical angle, and obtain the sinusoidal of the air gap magnetic density based on the representation relationship between the air gap magnetomotive force and the air gap magnetic density; and determine the analytical relationship between the change of the air gap length value with the electrical angle based on the sinusoidal nature of the air gap magnetic density.

[0146] Furthermore, the noise optimization device for the motor rotor also includes a simplification module 604, which is used to simplify the analytical relationship between the change of the air gap length value with the electrical angle according to the ratio of the magnetomotive force of the armature winding of the motor rotor to the magnetomotive force generated by the permanent magnet, so as to obtain a simplified relationship between the change of the air gap length value with the electrical angle; accordingly, the rotor optimization module 603 is also used to optimize the motor rotor according to the industrialization requirements of the air gap through the simplified relationship between the change of the air gap length value with the electrical angle, so as to obtain a low-noise rotor structure.

[0147] Furthermore, the rotor optimization module 603 is also used to determine the air gap compensation value of the motor rotor under load according to the industrial requirements of the air gap through the simplified relationship between the air gap length value and the electrical angle; determine the stator and rotor air gap by asymmetric cutting of the original rotor structure and the air gap compensation value; and obtain a low-noise rotor structure based on the stator and rotor air gap.

[0148] Other embodiments or specific implementation methods of the noise optimization device for the motor rotor of the present application can refer to the above-mentioned method embodiments and will not be repeated here.

[0149] The noise optimization device for the motor rotor provided in the present application adopts the noise optimization method for the motor rotor in the above-mentioned embodiment, which can solve the technical problem that the conventional motor rotor will generate large vibrations during operation, resulting in high noise, which seriously affects the user experience. Compared with the prior art, the beneficial effects of the noise optimization device for the motor rotor provided in the present application are the same as the beneficial effects of the noise optimization method for the motor rotor provided in the above-mentioned embodiment, and the other technical features in the noise optimization device for the motor rotor are the same as the features disclosed in the above-mentioned embodiment method, which will not be repeated here.

[0150] The present application provides a noise optimization device for a motor rotor, and the noise optimization device for a motor rotor includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the noise optimization method for the motor rotor in the above-mentioned embodiment one.

[0151] Reference below Figure 7 , Figure 7 The device structure diagram of the hardware operating environment involved in the noise optimization method of the motor rotor in the embodiment of the present application shows a schematic diagram of the structure of the noise optimization device of the motor rotor suitable for implementing the embodiment of the present application. The noise optimization device of the motor rotor in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 7 The noise optimization device for the motor rotor shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0152] like Figure 7As shown, the noise optimization device for the motor rotor may include a processing device 1001 (such as a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. Various programs and data required for the operation of the noise optimization device for the motor rotor are also stored in the RAM 1004. The processing device 1001, the ROM 1002, and the RAM 1004 are connected to each other via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; storage devices 1003 including, for example, a magnetic tape, a hard disk, etc.; and communication devices 1009. The communication device 1009 can allow the noise optimization device for the motor rotor to communicate with other devices wirelessly or by wire to exchange data. Although the figure shows the noise optimization device for the motor rotor with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems may be implemented or have instead.

[0153] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0154] The noise optimization device for the motor rotor provided in the present application adopts the noise optimization method for the motor rotor in the above embodiment, which can solve the technical problem that the conventional motor rotor will generate large vibrations during operation, resulting in high noise, which seriously affects the user experience. Compared with the prior art, the beneficial effects of the noise optimization device for the motor rotor provided in the present application are the same as the beneficial effects of the noise optimization method for the motor rotor provided in the above embodiment, and the other technical features of the noise optimization device for the motor rotor are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0155] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0156] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0157] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the noise optimization method for the motor rotor in the above-mentioned embodiment.

[0158] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0159] The computer-readable storage medium may be included in the noise optimization device for the motor rotor; or may exist independently without being assembled into the noise optimization device for the motor rotor.

[0160] The computer-readable storage medium carries one or more programs. When the one or more programs are executed by the noise optimization device of the motor rotor, the noise optimization device of the motor rotor: determines the sinusoidality of the air gap magnetic density based on the analytical relationship between the low noise and magnetic density of the motor rotor; constructs the analytical relationship between the air gap length and the magnetomotive force through the sinusoidality of the air gap magnetic density; optimizes the motor rotor according to the industrialization requirements of the air gap through the analytical relationship between the air gap length and the magnetomotive force to obtain a low-noise rotor structure to optimize the noise of the motor rotor.

[0161] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0162] The flowchart and block diagram in the accompanying drawings illustrate the possible architecture, functions and operations of the system, method and computer program product according to various embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0163] The modules involved in the embodiments described in the present application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0164] The readable storage medium provided in the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the noise optimization method of the motor rotor described above, and can solve the technical problem that the conventional motor rotor generates large vibrations during operation, resulting in high noise, which seriously affects the user experience. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in the present application are the same as the beneficial effects of the noise optimization method of the motor rotor provided in the above embodiment, and will not be elaborated here.

[0165] The present application also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the steps of the noise optimization method for a motor rotor as described above are implemented.

[0166] The computer program product provided by the present application can solve the technical problem that the conventional motor rotor generates large vibrations during operation, resulting in high noise, which seriously affects the user experience. Compared with the prior art, the beneficial effects of the computer program product provided by the present application are the same as those of the noise optimization method for the motor rotor provided by the above embodiment, and will not be elaborated here.

[0167] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A method for optimizing the noise of a motor rotor, characterized in that: The method includes: According to the analytical relationship between the low noise of the motor rotor and the magnetic flux density, the sinusoidal nature of the air gap magnetic flux density is determined; By using the sinusoidal property of the air gap magnetic flux density, an analytical relationship between the air gap length and the magnetomotive force is constructed; By means of the analytical relationship between the air gap length and the magnetomotive force, the motor rotor is optimized according to the industrial requirements of the air gap to obtain a low-noise rotor structure, thereby optimizing the noise of the motor rotor.

2. The method according to claim 1, characterized in that The step of determining the sinusoidality of the air gap magnetic flux density according to the analytical relationship between the low noise and magnetic flux density of the motor rotor comprises: According to the radial electromagnetic force density, the non-zero-order spatial force wave stator displacement of the motor rotor is determined; By means of the non-zero-order spatial force wave stator displacement, an analytical relationship between low noise and magnetic flux density is constructed; According to the analytical relationship between the low noise and the magnetic flux density, the sinusoidality of the air gap magnetic flux density of the motor rotor is determined.

3. The method according to claim 1, characterized in that The step of constructing an analytical relationship between air gap length and magnetomotive force through the sinusoidality of the air gap magnetic flux density comprises: Determining an analytical relationship for the total air gap magnetomotive force of the motor rotor when under load; When the requirement of the sinusoidality of the air gap magnetic flux density is met, an analytical relationship between the air gap length and the magnetomotive force is constructed according to the analytical relationship of the total air gap magnetomotive force.

4. The method according to claim 3, characterized in that The step of constructing an analytical relationship between air gap length and magnetomotive force according to the analytical relationship of the total air gap magnetomotive force comprises: Determine the expression relationship between the air gap magnetomotive force and the air gap magnetic flux density according to the analytical relationship of the air gap magnetomotive force; The air gap length that does not change with the electrical angle is designed to be an air gap length value that changes with the electrical angle, and based on the expression relationship between the air gap magnetomotive force and the air gap magnetic flux density, the sinusoidal property of the air gap magnetic flux density is obtained; According to the sinusoidality of the air gap magnetic flux density, an analytical relationship between the change of the air gap length value and the electrical angle is determined.

5. The method according to claim 4, characterized in that After the step of determining the analytical relationship between the air gap length value and the electrical angle according to the sinusoidality of the air gap magnetic flux, the method further includes: According to the ratio of the magnetomotive force of the armature winding of the motor rotor to the magnetomotive force generated by the permanent magnet, the analytical relationship between the change of the air gap length value with the electrical angle is simplified to obtain a simplified relationship between the change of the air gap length value with the electrical angle; Accordingly, the step of optimizing the motor rotor according to the air gap industrialization requirements through the analytical relationship between the air gap length and the magnetomotive force to obtain a low-noise rotor structure includes: According to the requirements of air gap industrialization, the motor rotor is optimized through the simplified relationship between the air gap length value and the electrical angle, so as to obtain a low-noise rotor structure.

6. The method according to claim 5, characterized in that The step of optimizing the motor rotor according to the industrial requirements of the air gap through the simplified relationship between the air gap length value and the electrical angle to obtain a low-noise rotor structure includes: According to the requirements of air gap industrialization, the air gap compensation value of the motor rotor under load is determined through the simplified relationship between the air gap length value and the electrical angle; Determine the stator-rotor air gap by asymmetrically cutting the original rotor structure and the air gap compensation value; Based on the stator-rotor air gap, a low-noise rotor structure is obtained.

7. A noise optimization device for a motor rotor, characterized in that: The device comprises: The sinusoidal module is used to determine the sinusoidal nature of the air gap flux density based on the analytical relationship between the low noise and flux density of the motor rotor; An air gap length module, used to construct an analytical relationship between air gap length and magnetomotive force through the sinusoidal nature of the air gap magnetic flux density; The rotor optimization module is used to optimize the motor rotor according to the air gap industrialization requirements through the analytical relationship between the air gap length and the magnetomotive force, so as to obtain a low-noise rotor structure.

8. A noise optimization device for a motor rotor, characterized in that: The device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the noise optimization method for a motor rotor according to any one of claims 1 to 6.

9. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the noise optimization method for the motor rotor as described in any one of claims 1 to 6 are implemented.

10. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the steps of the noise optimization method for a motor rotor according to any one of claims 1 to 6 are implemented.

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