Method, device, equipment and medium for determining motor rotor structure

Abstract

The present invention discloses a method, device, equipment and medium for determining the structure of a motor rotor, and belongs to the technical field of motor design. The method includes: determining the first-order modal frequency and the first-order critical speed of the rotor in response to the modal analysis results of the motor rotor; determining the target frequency avoidance frequency that the rotor design needs to avoid according to the number of magnetic poles of the motor stator and the number of slots on the motor rotor; when the first-order modal frequency and the first-order critical speed meet the set requirements, output the current rotor structure; otherwise, adjust the structure of the rotor until the first-order modal frequency and the first-order critical speed meet the set requirements, and output the improved rotor structure; wherein the set requirements include: the first-order modal frequency is greater than the target frequency avoidance frequency, and the first-order critical speed is greater than the preset maximum design speed of the motor rotor. The use of this method can avoid the problem of rotor resonance in the design stage of the motor rotor, while ensuring that the rotor will not generate bending vibration during high-speed operation.

Description

Technical Field

[0001] The present invention relates to the technical field of motor design, and in particular to a method, device, equipment and medium for determining a motor rotor structure. Background Art

[0002] The rotor is an important part of the motor, which is mainly composed of the rotor punching assembly, the balance ring and the rotor shaft. Its characteristics have an important impact on the working stability of the motor. The vibration of the rotor will cause the motor to resonate or fail due to fatigue, thereby destroying the motor structure, affecting the air gap magnetic flux density of the motor, and causing the overall performance of the motor to deteriorate.

[0003] Therefore, how to avoid rotor resonance during the motor design stage is a technical problem that needs to be solved urgently. Summary of the invention

[0004] In view of the above problems, the present invention provides a method, device, equipment and medium for determining a motor rotor structure that overcomes the above problems or at least partially solves the above problems. The method can determine the operating frequency of the rotor according to the modal analysis results of the rotor, and determine the natural frequency of the motor structure as the target avoidance frequency according to the number of magnetic poles of the motor stator and the number of slots on the motor rotor, so as to avoid the problem of rotor resonance in the design stage of the motor rotor, and at the same time ensure that the rotor will not generate bending vibration during high-speed operation.

[0005] In a first aspect, the present invention provides a method for determining a motor rotor structure, the method comprising:

[0006] In response to the modal analysis results of the motor rotor, determining the first-order modal frequency and the first-order critical speed of the rotor;

[0007] According to the number of magnetic poles on the motor stator and the number of slots on the motor rotor, determine the target frequency that the rotor design needs to avoid;

[0008] When the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements, the current rotor structure is output; otherwise, the rotor structure is adjusted until the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements, and the improved rotor structure is output;

[0009] Wherein, the setting requirements include: the first-order modal frequency of the rotor is greater than the target frequency avoidance frequency, and the first-order critical speed of the rotor is greater than the preset maximum design speed of the motor rotor.

[0010] Optionally, determining the target avoidance frequency that the rotor design needs to avoid according to the number of magnetic poles of the motor stator and the number of slots on the motor rotor includes:

[0011] When the number of magnetic poles of the motor stator is n and the number of slots on the motor rotor is m, the target frequency avoidance frequencies to be avoided by the rotor design are determined to be nHz and mHz.

[0012] Optionally, the structure of the adjusting rotor includes:

[0013] The material parameters of each rotor component are adjusted, wherein the material parameters at least include density, Young's modulus, Poisson's ratio and mass.

[0014] Optionally, before determining the first-order modal frequency and the first-order critical speed of the rotor, the method further includes:

[0015] Based on a pre-established rotor assembly model, configuring simulation parameters of the rotor assembly model, wherein the simulation parameters at least include material parameters, contact conditions, and load conditions of various rotor components;

[0016] The rotor assembly model is divided into finite element grids, and finite element analysis calculations are performed on the rotor assembly model to output modal analysis results of the motor rotor, wherein the modal analysis results include the natural frequency and critical speed of the motor rotor in each order mode.

[0017] Optionally, the simulation parameters for configuring the rotor assembly model include:

[0018] In the axial direction of the rotor, the contact condition between the silicon steel sheets in the punching sheet assembly configured with the rotor is friction non-separation contact, and the contact condition between the balance ring configured with the rotor and the silicon steel sheets is binding contact;

[0019] In the radial direction of the rotor, the contact condition between the rotor shaft of the rotor and the balance ring, and between the rotor shaft and each silicon steel sheet is binding contact.

[0020] In a second aspect, the present invention provides a device for determining a motor rotor structure, the device comprising:

[0021] A first determination module, configured to determine a first-order modal frequency and a first-order critical speed of the rotor in response to a modal analysis result of the motor rotor;

[0022] The second determination module is used to determine the target avoidance frequency that the rotor needs to avoid according to the number of magnetic poles of the motor stator and the number of slots on the motor rotor;

[0023] An analysis module, configured to output a current rotor structure when the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements; otherwise, adjust the rotor structure until the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements, and output an improved rotor structure;

[0024] Wherein, the setting requirements include: the first-order modal frequency of the rotor is greater than the target frequency avoidance frequency, and the first-order critical speed of the rotor is greater than the preset maximum design speed of the motor rotor.

[0025] Optionally, the second determining module is used to:

[0026] When the number of magnetic poles of the motor stator is n and the number of slots on the motor rotor is m, the target frequency avoidance frequencies to be avoided by the rotor design are determined to be nHz and mHz.

[0027] Optionally, the analysis module is used to:

[0028] The material parameters of each rotor component are adjusted, wherein the material parameters at least include density, Young's modulus, Poisson's ratio and mass.

[0029] Optionally, the determining device further includes:

[0030] A model parameter configuration module, configured to configure simulation parameters of the rotor assembly model based on a pre-established rotor assembly model, wherein the simulation parameters at least include material parameters, contact conditions, and load conditions of various rotor components;

[0031] The simulation analysis module is used to divide the rotor assembly model into finite element grids, perform finite element analysis calculations on the rotor assembly model, and output modal analysis results of the motor rotor, wherein the modal analysis results include the natural frequency and critical speed of the motor rotor in each order mode.

[0032] Optionally, the model parameter configuration module is used to:

[0033] In the axial direction of the rotor, the contact condition between the silicon steel sheets in the punching sheet assembly configured with the rotor is friction non-separation contact, and the contact condition between the balance ring configured with the rotor and the silicon steel sheets is binding contact;

[0034] In the radial direction of the rotor, the contact condition between the rotor shaft of the rotor and the balance ring, and between the rotor shaft and each silicon steel sheet is binding contact.

[0035] In a third aspect, the present invention provides an electronic device comprising: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, computer instructions are stored in the memory, and the processor executes the determination method described in the first aspect by executing the computer instructions.

[0036] In a fourth aspect, the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable the computer to execute the determination method as described in the first aspect.

[0037] The technical solution provided in the embodiments of the present invention has at least the following technical effects or advantages:

[0038] The embodiment of the present invention provides a method, device, equipment and medium for determining the structure of a motor rotor. The method can determine the first-order modal frequency and the first-order critical speed of the rotor according to the modal analysis results of the rotor; determine the natural frequency of the motor structure according to the number of magnetic poles of the motor stator and the number of slots on the motor rotor, and use the natural frequency of the motor structure as the target frequency avoidance frequency to be avoided in the rotor design, so that the motor rotor can avoid the problem of rotor resonance in the design stage. The rotor structure is output only when the first-order critical speed of the rotor is greater than the preset maximum design speed of the motor rotor, which can ensure that the rotor will not generate bending vibration during high-speed operation.

[0039] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0041] Figure 1 is a flow chart of a method for determining a motor rotor structure provided by an embodiment of the present invention;

[0042] Figure 2 is a schematic diagram of a model of a rotor assembly provided by an embodiment of the present invention;

[0043] Figure 3 is a structural schematic diagram of a balancing ring provided by an embodiment of the present invention;

[0044] Figure 4 is a schematic structural diagram of a rotor shaft provided by an embodiment of the present invention;

[0045] Figure 5 is a schematic structural diagram of a rotor punching assembly provided by an embodiment of the present invention;

[0046] Figure 6 is a contact condition configuration schematic diagram provided by an embodiment of the present invention;

[0047] Figure 7 It is a structural block diagram of a device for determining a motor rotor structure provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0049] Various structural schematic diagrams according to embodiments of the present disclosure are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may further design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0050] Figure 1 is a flow chart of a method for determining a motor rotor structure provided by an embodiment of the present invention, such as Figure 1 As shown, the determination method includes:

[0051] Step S110 : In response to the modal analysis result of the motor rotor, determine the first-order modal frequency and the first-order critical speed of the rotor.

[0052] Optionally, before executing step S110, the method further includes:

[0053] Based on the pre-established rotor assembly model, configuring simulation parameters of the rotor assembly model, the simulation parameters at least including material parameters, contact conditions and load conditions of various rotor components;

[0054] The rotor assembly model is divided into finite element meshes, and the rotor assembly model is subjected to finite element analysis and calculation, and the modal analysis results of the motor rotor are output. The modal analysis results include the natural frequency and critical speed of the motor rotor in each mode.

[0055] Specifically, the rotor assembly model can be pre-established using three-dimensional modeling software, or the rotor assembly model can be directly established using finite element simulation analysis software. Then, the simulation parameters of the rotor assembly model are configured in the finite element simulation analysis software, and the rotor assembly model is meshed by finite elements, and then the rotor assembly model is subjected to finite element analysis calculation to output the modal analysis results of the motor rotor.

[0056] In this embodiment, when the rotor assembly model is meshed by finite element, the mesh size can be set to 6 mm in the finite element simulation analysis software. This mesh size can just mesh out each component of the rotor to ensure the accuracy of the simulation results.

[0057] In this embodiment, the first 20 frequencies of the rotor are calculated by finite element analysis, as shown in Table 1 below:

[0058] Mode Frequency[Hz] 1 1 97.336 2 2 155.82 3 3 1771.9 4 4 3284.8 5 5 4355.9 6 6 4357.2 7 7 4415.8 8 8 5160.6 9 9 5385.3 10 10 5386.7 11 11 5617 12 12 5873.8 13 13 5893.7 14 14 5952.3 15 15 6007.7 16 16 6385.1 17 17 6390.1 18 18 6557.6 19 19 6640.8 20 20 7422.5

[0059] Since the rotor structure is mainly affected by the modal analysis results at low order, the embodiment of the present invention mainly needs to determine the first-order modal frequency and the first-order critical speed of the rotor. As can be seen from Table 1 above, in this embodiment, the first-order modal frequency of the rotor is 97.336 Hz.

[0060] At the same time, in this embodiment, the global speed can be applied to the rotor assembly model in the finite element simulation analysis software, and the speed starts from 10000 rpm and gradually increases to 50000 rpm with a step size of 5000 rpm. Then, displacement support is added to the rotor bearing to release the rotational freedom and limit the axial and radial freedom. The critical speed of the rotor at each order can be obtained through the Campbell diagram. For example, in this embodiment, the first-order resonance critical speed of the rotor is 27500 rpm.

[0061] Figure 2 is a schematic diagram of a model of a rotor assembly provided by an embodiment of the present invention, Figure 3 is a schematic diagram of the structure of a balancing ring provided by an embodiment of the present invention, Figure 4 is a schematic structural diagram of a rotor shaft provided by an embodiment of the present invention, Figure 5 is a schematic diagram of the structure of a rotor punching assembly provided by an embodiment of the present invention, such as Figures 2 to 5 As shown, the rotor assembly 20 includes two balancing rings 21, a rotor shaft 22 and a rotor punching assembly 23. The balancing rings 21 and the rotor punching assembly 23 are both sleeved outside the rotor shaft 22, and the two balancing rings 21 are located at both ends of the rotor punching assembly 23. The rotor punching assembly 23 is composed of a plurality of silicon steel sheets 231.

[0062] In this embodiment, the rotor punching assembly 23 may include eight silicon steel sheets 231 , and the eight silicon steel sheets 231 are in frictional non-separation contact with each other.

[0063] Optionally, configure the contact conditions of the rotor assembly model to include:

[0064] In the axial direction of the rotor, the contact condition between the silicon steel sheets in the punching sheet assembly configured with the rotor is friction non-separation contact, and the contact condition between the balance ring configured with the rotor and the silicon steel sheet is binding contact;

[0065] In the radial direction of the rotor, the contact condition between the rotor shaft and the balance ring of the rotor, and between the rotor shaft and each silicon steel sheet is binding contact.

[0066] Figure 6 is a schematic diagram of a contact condition configuration provided by an embodiment of the present invention, such as Figure 6As shown, in the axial direction of the rotor, the contact condition between each silicon steel sheet 231 in the figure is configured as friction non-separation contact, and the contact condition between the two balancing rings 21 and the silicon steel sheet 231 is configured as binding contact. In the radial direction of the rotor, the contact condition between the rotor shaft 22 and the two balancing rings 21, and between the rotor shaft 22 and each silicon steel sheet 231 is configured as binding contact. This contact condition is more in line with the contact condition between the actual components of the rotor, which is conducive to improving the accuracy of the rotor modal analysis results.

[0067] Step S120: determining a target frequency that the rotor needs to avoid in design according to the number of magnetic poles of the motor stator and the number of slots on the motor rotor.

[0068] Optionally, step S120 includes:

[0069] When the number of magnetic poles of the motor stator is n and the number of slots on the motor rotor is m, the target avoidance frequencies that the rotor design needs to avoid are determined as nHz and mHz.

[0070] In one implementation of this embodiment, a 6-stage 48-slot motor is taken as an example. At this time, when the number of magnetic poles of the motor stator is n=6 and the number of slots on the motor rotor is m=48, it can be determined that the target frequency avoidance frequencies that the rotor design needs to avoid are 6 Hz and 48 Hz. In other implementations of this embodiment, motors with other numbers of stages or slots may also be used, and this embodiment does not limit this.

[0071] Step S130: When the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements, the current rotor structure is output; otherwise, the rotor structure is adjusted until the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements, and the improved rotor structure is output.

[0072] The setting requirements include: the first-order modal frequency of the rotor is greater than the target avoidance frequency, and the first-order critical speed of the rotor is greater than the preset maximum design speed of the motor rotor.

[0073] That is to say, when the first-order modal frequency of the rotor is less than or equal to the target avoidance frequency, or when the first-order critical speed of the rotor is less than or equal to the preset maximum design speed of the motor rotor, it is necessary to adjust the structure of the rotor until the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements.

[0074] For example, when the target frequency avoidance frequency in this embodiment is 6 Hz and 48 Hz, it can be seen from Table 1 above that when the first-order modal frequency of the rotor is 97.336 Hz, which is greater than the target frequency avoidance frequency, when the first-order critical speed of the rotor is less than or equal to the preset maximum design speed of the motor rotor, it can be determined that the current rotor structure is reasonable and can play a vibration avoidance role, and at this time, the current rotor structure can be output.

[0075] Optionally, in step S130, adjusting the structure of the rotor may specifically include:

[0076] The material parameters of each rotor component are adjusted, and the material parameters at least include density, Young's modulus, Poisson's ratio and mass.

[0077] Among them, Young's modulus is a physical quantity that characterizes the tensile or compressive resistance of a material within the elastic limit. It is the elastic modulus along the longitudinal direction. Poisson's ratio refers to the ratio of the transverse normal strain to the axial normal strain when the material is subjected to unidirectional tension or compression, also called the transverse deformation coefficient. It is an elastic constant that reflects the transverse deformation of the material. The rotor structure can be optimized by adjusting the above material parameters.

[0078] A method for determining a motor rotor structure provided by an embodiment of the present invention can determine the first-order modal frequency and the first-order critical speed of the rotor according to the modal analysis results of the rotor; determine the natural frequency of the motor structure according to the number of magnetic poles of the motor stator and the number of slots on the motor rotor, and use the natural frequency of the motor structure as the target frequency avoidance frequency to be avoided in the rotor design, so that the motor rotor can avoid the problem of rotor resonance during the design stage. The rotor structure is output only when the first-order critical speed of the rotor is greater than the preset maximum design speed of the motor rotor, which can ensure that the rotor will not generate bending vibration during high-speed operation.

[0079] Based on the same inventive concept, an embodiment of the present invention further provides a device for determining a motor rotor structure. Figure 7 is a structural block diagram of a device for determining a motor rotor structure provided by an embodiment of the present invention, such as Figure 7 As shown, the control device 700 includes a first determination module 710 , a second determination module 720 and an analysis module 730 .

[0080] The first determination module 710 is used to determine the first-order modal frequency and the first-order critical speed of the rotor in response to the modal analysis result of the motor rotor.

[0081] The second determination module 720 is used to determine a target avoidance frequency that the rotor needs to avoid according to the number of magnetic poles of the motor stator and the number of slots on the motor rotor.

[0082] The analysis module 730 is used to output the current rotor structure when the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements; otherwise, adjust the rotor structure until the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements, and output the improved rotor structure.

[0083] The setting requirements include: the first-order modal frequency of the rotor is greater than the target avoidance frequency, and the first-order critical speed of the rotor is greater than the preset maximum design speed of the motor rotor.

[0084] That is to say, when the first-order modal frequency of the rotor is less than or equal to the target avoidance frequency, or when the first-order critical speed of the rotor is less than or equal to the preset maximum design speed of the motor rotor, it is necessary to adjust the structure of the rotor until the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements.

[0085] For example, when the target frequency avoidance frequency in this embodiment is 6 Hz and 48 Hz, if the first-order modal frequency of the rotor is 97.336 Hz, which is greater than the target frequency avoidance frequency. At the same time, when the first-order critical speed of the rotor is less than or equal to the preset maximum design speed of the motor rotor, it can be determined that the current rotor structure is reasonable and can play a vibration avoidance role. At this time, the current rotor structure can be output.

[0086] Optionally, the second determining module 720 is used to:

[0087] When the number of magnetic poles of the motor stator is n and the number of slots on the motor rotor is m, the target avoidance frequencies that the rotor design needs to avoid are determined as nHz and mHz.

[0088] In one implementation of this embodiment, a 6-stage 48-slot motor is taken as an example. At this time, when the number of magnetic poles of the motor stator is n=6 and the number of slots on the motor rotor is m=48, it can be determined that the target frequency avoidance frequencies that the rotor design needs to avoid are 6 Hz and 48 Hz. In other implementations of this embodiment, motors with other numbers of stages or slots may also be used, and this embodiment does not limit this.

[0089] Optionally, the analysis module 730 is used to:

[0090] The material parameters of each rotor component are adjusted, and the material parameters at least include density, Young's modulus, Poisson's ratio and mass.

[0091] Among them, Young's modulus is a physical quantity that characterizes the tensile or compressive resistance of a material within the elastic limit. It is the elastic modulus along the longitudinal direction. Poisson's ratio refers to the ratio of the transverse normal strain to the axial normal strain when the material is subjected to unidirectional tension or compression, also called the transverse deformation coefficient. It is an elastic constant that reflects the transverse deformation of the material. The rotor structure can be optimized by adjusting the above material parameters.

[0092] Optionally, the determining device 700 further includes:

[0093] A model parameter configuration module, used to configure simulation parameters of the rotor assembly model based on a pre-established rotor assembly model, wherein the simulation parameters at least include material parameters, contact conditions and load conditions of various rotor components;

[0094] The simulation analysis module is used to divide the rotor assembly model into finite element meshes, perform finite element analysis calculations on the rotor assembly model, and output the modal analysis results of the motor rotor. The modal analysis results include the natural frequency and critical speed of the motor rotor in each mode.

[0095] Specifically, the rotor assembly model can be pre-established using three-dimensional modeling software, or the rotor assembly model can be directly established using finite element simulation analysis software. Then, the simulation parameters of the rotor assembly model are configured in the finite element simulation analysis software, and the rotor assembly model is meshed by finite elements, and then the rotor assembly model is subjected to finite element analysis calculation to output the modal analysis results of the motor rotor.

[0096] In this embodiment, when the rotor assembly model is meshed by finite element, the mesh size can be set to 6 mm in the finite element simulation analysis software. This mesh size can just mesh out each component of the rotor to ensure the accuracy of the simulation results.

[0097] In this embodiment, the first 20 frequencies of the rotor can be obtained through finite element analysis. At the same time, in this embodiment, the global speed can be applied to the rotor assembly model in the finite element simulation analysis software, and the speed starts from 10000 rpm and gradually increases to 50000 rpm with a step size of 5000 rpm. Then, displacement support is added to the rotor bearing to release the rotational freedom and limit the axial and radial freedom. The critical speed of the rotor at each order can be obtained through the Campbell diagram.

[0098] Optionally, the model parameter configuration module is used to:

[0099] In the axial direction of the rotor, the contact condition between the silicon steel sheets in the punching sheet assembly configured with the rotor is friction non-separation contact, and the contact condition between the balance ring configured with the rotor and the silicon steel sheet is binding contact;

[0100] In the radial direction of the rotor, the contact condition between the rotor shaft and the balance ring of the rotor, and between the rotor shaft and each silicon steel sheet is binding contact.

[0101] It can be understood that the determination device provided in the above embodiment is only illustrated by the division of the above functional modules. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the determination device is divided into different functional modules to complete all or part of the functions described above.

[0102] An embodiment of the present invention further provides an electronic device, which may include a processor and a memory, wherein the processor and the memory may be communicatively connected to each other via a bus or other means.

[0103] The processor may be a central processing unit (CPU) or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0104] The memory may include a large capacity memory for data or instructions. By way of example and not limitation, the memory may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive or a combination of two or more of these. Where appropriate, the memory may include a removable or non-removable (or fixed) medium. Where appropriate, the memory may be inside or outside the electronic device. In a particular embodiment, the memory may be a non-volatile solid-state memory.

[0105] In one example, the memory may be a read-only memory (ROM). In one example, the ROM may be a mask-programmed ROM, a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), an electrically rewritable ROM (EAROM), or a flash memory, or a combination of two or more of these.

[0106] The processor implements any one of the determination methods in the above embodiments by reading and executing computer program instructions stored in the memory.

[0107] In one example, the electronic device may include a communication interface and a bus. Among them, the processor, memory, and communication interface are connected through the bus and communicate with each other. The communication interface is mainly used to realize the communication between the modules, devices, units and / or devices in the embodiments of the present application. Where appropriate, the bus may include one or more buses.

[0108] In addition, in combination with the determination method in the above embodiment, the embodiment of the present invention can provide a computer-readable storage medium for implementation. The computer-readable storage medium stores computer program instructions; when the computer program instructions are executed by a processor, any one of the determination methods in the above embodiment is implemented.

[0109] The technical solutions in the above embodiments of the present application have at least the following technical effects or advantages:

[0110] The embodiment of the present invention provides a method, device, equipment and medium for determining the structure of a motor rotor. The method can determine the first-order modal frequency and the first-order critical speed of the rotor according to the modal analysis results of the rotor; determine the natural frequency of the motor structure according to the number of magnetic poles of the motor stator and the number of slots on the motor rotor, and use the natural frequency of the motor structure as the target frequency avoidance frequency to be avoided in the rotor design, so that the motor rotor can avoid the problem of rotor resonance in the design stage. The rotor structure is output only when the first-order critical speed of the rotor is greater than the preset maximum design speed of the motor rotor, which can ensure that the rotor will not generate bending vibration during high-speed operation.

[0111] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0112] Similarly, it should be understood that in order to streamline the present disclosure and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, this disclosed method should not be interpreted as reflecting the intention that the claimed invention requires more features than those explicitly recited in each claim. More specifically, as reflected in the claims below, inventive aspects lie in less than all the features of the individual embodiments disclosed above. Therefore, the claims that follow the specific embodiment are hereby expressly incorporated into the specific embodiment, with each claim itself serving as a separate embodiment of the present invention.

[0113] It should be noted that the above embodiments illustrate the present invention rather than limit it, and that those skilled in the art may devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets shall not be construed as a limitation on the claims. The word "comprising" does not exclude the presence of components or steps not listed in the claims. The word "one" or "an" preceding a component does not exclude the presence of a plurality of such components. The present invention may be implemented by means of hardware comprising a number of different components and by means of a suitably programmed computer. In a unit claim enumerating a number of devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third, etc., does not indicate any order. These words may be interpreted as names.

Claims

1. A method for determining a motor rotor structure, characterized in that: The determination method comprises: In response to the modal analysis results of the motor rotor, determining the first-order modal frequency and the first-order critical speed of the rotor; According to the number of magnetic poles on the motor stator and the number of slots on the motor rotor, determine the target frequency that the rotor design needs to avoid; When the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements, the current rotor structure is output; otherwise, the rotor structure is adjusted until the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements, and the improved rotor structure is output; Wherein, the setting requirements include: the first-order modal frequency of the rotor is greater than the target frequency avoidance frequency, and the first-order critical speed of the rotor is greater than the preset maximum design speed of the motor rotor; Determining the target frequency avoidance frequency to be avoided by the rotor design according to the number of magnetic poles of the motor stator and the number of slots on the motor rotor includes: When the number of magnetic poles of the motor stator is n and the number of slots on the motor rotor is m, the target frequency avoidance frequencies to be avoided by the rotor design are determined to be nHz and mHz; Before determining the first-order modal frequency and the first-order critical speed of the rotor, the method further includes: Based on a pre-established rotor assembly model, configuring simulation parameters of the rotor assembly model, wherein the simulation parameters at least include material parameters, contact conditions, and load conditions of various rotor components; Performing finite element meshing on the rotor assembly model, and performing finite element analysis calculation on the rotor assembly model, and outputting modal analysis results of the motor rotor, wherein the modal analysis results include the natural frequency and critical speed of the motor rotor in each order mode; The simulation parameters for configuring the rotor assembly model include: In the axial direction of the rotor, the contact condition between the silicon steel sheets in the punching sheet assembly configured with the rotor is friction non-separation contact, and the contact condition between the balance ring configured with the rotor and the silicon steel sheets is binding contact; In the radial direction of the rotor, the contact condition between the rotor shaft of the rotor and the balance ring, and between the rotor shaft and each silicon steel sheet is binding contact.

2. The determination method according to claim 1, characterized in that: The structure of the adjusting rotor comprises: The material parameters of each rotor component are adjusted, wherein the material parameters at least include density, Young's modulus, Poisson's ratio and mass.

3. A device for determining a motor rotor structure, characterized in that: The determining device comprises: A first determination module, configured to determine a first-order modal frequency and a first-order critical speed of the rotor in response to a modal analysis result of the motor rotor; The second determination module is used to determine the target avoidance frequency that the rotor needs to avoid according to the number of magnetic poles of the motor stator and the number of slots on the motor rotor; An analysis module, configured to output a current rotor structure when the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements; otherwise, adjust the rotor structure until the first-order modal frequency and the first-order critical speed of the rotor meet the set requirements, and output an improved rotor structure; Wherein, the setting requirements include: the first-order modal frequency of the rotor is greater than the target frequency avoidance frequency, and the first-order critical speed of the rotor is greater than the preset maximum design speed of the motor rotor; The second determining module is used for: When the number of magnetic poles of the motor stator is n and the number of slots on the motor rotor is m, the target frequency avoidance frequencies to be avoided by the rotor design are determined to be nHz and mHz. The determining device also includes: A model parameter configuration module, configured to configure simulation parameters of the rotor assembly model based on a pre-established rotor assembly model, wherein the simulation parameters at least include material parameters, contact conditions, and load conditions of various rotor components; A simulation analysis module, used for performing finite element meshing on the rotor assembly model, performing finite element analysis calculation on the rotor assembly model, and outputting modal analysis results of the motor rotor, wherein the modal analysis results include the natural frequency and critical speed of the motor rotor in each order mode; The model parameter configuration module is also used for: In the axial direction of the rotor, the contact condition between the silicon steel sheets in the punching sheet assembly configured with the rotor is friction non-separation contact, and the contact condition between the balance ring configured with the rotor and the silicon steel sheets is binding contact; In the radial direction of the rotor, the contact condition between the rotor shaft of the rotor and the balance ring, and between the rotor shaft and each silicon steel sheet is binding contact.

4. An electronic device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the determination method described in claim 1 or 2 by executing the computer instructions.

5. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable the computer to execute the determination method according to claim 1 or 2.

Images