Simulation method of comprehensive environmental reliability of motor working state based on ANSYS

Abstract

The present application provides a motor operating state comprehensive environmental reliability simulation method based on ANSYS, comprising the following steps: establishing a geometric model of the motor stator and rotor assembly based on ANSYS; determining the materials of the stator and rotor assemblies and meshing the stator and rotor assemblies respectively, loading and setting the piezoelectric properties of the piezoelectric ceramics and applying constraint boundaries to obtain the motor electromechanical model; obtaining the temperature field, random vibration field, and centrifugal force field of the motor; selecting three data modules to read the temperature field, random vibration field, and centrifugal force field respectively, and using the three data modules as parameter setting options for the motor electromechanical model; inserting the frequency response curve function, impedance curve function, and node force function to obtain the operating frequency and operating amplitude, voltage component impedance, and stall torque under the actual operation of the motor. The motor operating state comprehensive environmental reliability simulation method based on ANSYS provided in the present application can obtain more comprehensive motor output characteristics under a comprehensive environment.

Description

Technical Field

[0001] The present disclosure generally relates to the technical fields of electromechanical simulation and multi-stress coupling simulation, and in particular to an ANSYS-based simulation method for comprehensive environmental reliability of motor working conditions. Background Art

[0002] Ultrasonic motors have the advantages of high positioning and speed control accuracy, flexible structural design, easy miniaturization and lightweighting, and immunity to and non-inducing electromagnetic interference. They are widely used in related fields such as precision drives. As the technology matures, ultrasonic motors are also very suitable for drive and private service systems of various types of weapons and spacecraft. Unlike civilian ultrasonic motors, ultrasonic motors used in missiles or spacecraft will experience harsh comprehensive launch environments along with the aircraft, and may even need to operate in some comprehensive flight environments. In this case, the probability of ultrasonic motors experiencing various types of performance deviations or failures will be significantly increased. In order to ensure the high reliability of ultrasonic motors in weapons and spacecraft, it is of great significance to study the impact of the harsh comprehensive environment during the launch phase on the operating characteristics of ultrasonic motors.

[0003] Regarding the impact of the environment on ultrasonic motors, many researchers abroad have pioneered research on the motor's performance in abnormal and vacuum environments, particularly under ultra-high and low temperatures, and conducted related exploratory work. However, these efforts have largely focused on reporting only experimental conclusions, with much key data remaining undisclosed. Domestically, while some research institutes and universities with considerable technical expertise and experience in ultrasonic motor development have focused their research on civilian applications and single environmental stresses, such as high and low temperatures. Consequently, there are few reports on the impact of specialized, combined environmental stresses on ultrasonic motor performance. Research on combined environmental reliability can be conducted through testing and analysis of actual mission data. However, combined environmental testing is often limited by the capabilities of existing test equipment, and data on ultrasonic motor applications in weapons and spacecraft is scarce or unavailable. Therefore, this paper utilizes simulation software to conduct reliability simulations based on a typical launch environment characterized by temperature, random vibration, and centrifugal forces. This model, modified and validated through single-stress testing, provides a promising technical solution for studying the impact of combined environmental stresses on the output characteristics of ultrasonic motors. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, it is desired to provide an ANSYS-based motor operating state comprehensive environmental reliability simulation method to solve the above-mentioned problems.

[0005] The present application provides a motor operating state comprehensive environmental reliability simulation method based on ANSYS, comprising the following steps:

[0006] S100, establish the geometric model of the motor stator assembly and rotor assembly based on ANSYS;

[0007] S200, determining the materials of the stator assembly and the rotor assembly based on ANSYS, meshing the stator assembly and the rotor assembly respectively, loading and setting the piezoelectric properties of the piezoelectric ceramics and applying constraint boundaries to obtain an electromechanical model of the motor;

[0008] S300, obtaining a temperature field, a random vibration field, and a centrifugal force field of the motor through the electromechanical model of the motor based on ANSYS, wherein the temperature field is used to characterize the temperature stress distribution of the motor, the random vibration field is used to characterize the random vibration distribution of the motor, and the centrifugal force field is used to characterize the centrifugal stress distribution of the motor;

[0009] S400, selecting three data modules based on ANSYS to read the temperature field, random vibration field, and centrifugal force field respectively, and adding the three data modules to the motor electromechanical model as parameter setting options of the model to obtain the motor electromechanical model under a comprehensive environment;

[0010] S500 , based on the electromechanical model of the motor in the comprehensive environment of ANSYS, insert a frequency response curve function to obtain the operating frequency and operating amplitude of the motor, insert an impedance curve function to obtain the voltage component impedance, and insert a node force function to obtain the stall torque.

[0011] According to the technical solution provided in the embodiment of the present application, the method for obtaining the temperature field is:

[0012] Calculating the heat loss of the motor in a working state based on the motor electromechanical model;

[0013] Obtaining a heat load at each position of the motor according to the heat loss, and applying the heat load to a steady-state thermal analysis module;

[0014] Setting a thermal boundary in the steady-state thermal analysis module;

[0015] The steady-state thermal analysis module is solved and the results are added to the static analysis module, where a preload is applied and the temperature field is solved.

[0016] According to the technical solution provided in the embodiment of the present application, the formula for calculating the heat loss is as follows:

[0017]

[0018] T y =F n μ,

[0019] Among them, U is the motor input voltage, I is the motor input current, n is the motor speed, T2 is the output torque, Ty is the preload torque, F n is the applied preload, μ is the friction coefficient between the stator tooth surface and the rotor, P R is the structural loss and dielectric loss of the piezoelectric ceramic, P f is the friction loss between the stator and rotor contact surface, P s is the loss within the structure caused by stator vibration.

[0020] According to the technical solution provided in the embodiment of the present application, the method of applying the heat load is:

[0021] In the steady-state analysis module, P f As a load applied to the surface of the friction material, P R The first heat generation rate q R The load is added to the entire piezoelectric ceramic body, R The second heat generation rate q s The load form is added to the stator as a whole, the first heat generation rate q R The calculation formula is as follows:

[0022]

[0023] Among them, V R is the volume of piezoelectric ceramics;

[0024] The second heat generation rate q s The calculation formula is as follows:

[0025]

[0026] Among them, V s Stator volume.

[0027] According to the technical solution provided in the embodiment of the present application, the method for obtaining the random vibration field is:

[0028] Applying a preload force in a static analysis module based on the motor electromechanical model, and solving the static analysis module to obtain a first prestress field caused by the preload force;

[0029] adding the first prestressed field to a modal analysis module and solving the modal analysis module;

[0030] The results of the modal analysis are added to a random vibration analysis module, and the vibration conditions of the motor when it is actually working are added to the random vibration analysis module, and the random vibration analysis module is solved to obtain the random vibration field.

[0031] According to the technical solution provided in the embodiment of the present application, the method for obtaining the centrifugal force field is:

[0032] Based on the electromechanical model of the motor, the centrifugal force during actual operation of the motor is added to the static analysis module, and the static analysis module is solved to obtain the centrifugal force field.

[0033] According to the technical solution provided in the embodiment of the present application, step S500 includes:

[0034] Based on the electromechanical model of the motor in the comprehensive environment, the frequency response curve function of ANSYS is inserted into a certain stator tooth surface in the harmonic response analysis module to obtain the operating frequency and operating amplitude of the motor in the comprehensive environment, the impedance curve function of ANSYS is inserted into the piezoelectric ceramic to obtain the voltage component impedance of the motor, and the node force function of ANSYS is inserted into the contact pair of a certain stator tooth surface and the rotor to obtain the stall torque of the motor.

[0035] According to the technical solution provided in the embodiment of the present application, the calculation formula of the stall torque T is as follows:

[0036] T=krμF max ,

[0037] Among them, k is the working wave number, r is the rotor radius, F max is the maximum normal contact force on the target stator tooth surface.

[0038] Compared with the prior art, the beneficial effect of the present application is that: by setting the motor electromechanical model and setting the temperature parameters, random vibration parameters and centrifugal force parameters of the motor electromechanical model respectively, the motor temperature field, random vibration field and centrifugal stress field are simulated respectively, and three data modules are selected to read the temperature field, random vibration field and centrifugal force field respectively and add the data modules to the motor electromechanical model as parameter setting options of the model, which is equivalent to adding three restrictive conditions in different environments that can affect the model output to the motor electromechanical model, so that the model can obtain output characteristics under the influence of more environmental factors; inserting the frequency response curve function into the motor electromechanical model under the comprehensive environment can obtain the operating frequency and operating amplitude of the motor under actual operation, by inserting the impedance curve function, the voltage component impedance of the motor under actual operation can be obtained, and by inserting the node force function, the stall torque of the motor under actual operation can be obtained. By inserting the three functions, the motor electromechanical model under the comprehensive environment has more comprehensive output characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0040] Figure 1 The application provides a flowchart of the steps of the motor working state comprehensive environmental reliability simulation method based on ANSYS:

[0041] Figure 2 The geometric model of the stator assembly and the rotor assembly in this application;

[0042] Figure 3 for Figure 2 Exploded views of the stator and rotor assembly geometric models are shown;

[0043] Figure 4 Schematic diagram of the partitioning of piezoelectric ceramics in this application. DETAILED DESCRIPTION

[0044] The present application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the relevant invention and are not intended to limit the invention. It should also be noted that, for ease of description, only portions relevant to the invention are shown in the accompanying drawings.

[0045] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0046] Please refer to Figure 1 The present application provides a motor working state comprehensive environment reliability simulation method based on ANSYS, comprising the following steps:

[0047] S100, establish the geometric model of the motor stator assembly and rotor assembly based on ANSYS;

[0048] S200, determining the materials of the stator assembly and the rotor assembly based on ANSYS, meshing the stator assembly and the rotor assembly respectively, loading and setting the piezoelectric properties of the piezoelectric ceramics and applying constraint boundaries to obtain an electromechanical model of the motor;

[0049] S300, obtaining a temperature field, a random vibration field, and a centrifugal force field of the motor using an electromechanical model of the motor based on ANSYS, wherein the temperature field is used to characterize the temperature stress distribution of the motor, the random vibration field is used to characterize the random vibration distribution of the motor, and the centrifugal force field is used to characterize the centrifugal stress distribution of the motor;

[0050] S400, selecting three data modules based on ANSYS to read the temperature field, random vibration field, and centrifugal force field respectively, and adding the three data modules to the motor electromechanical model as parameter setting options of the model to obtain the motor electromechanical model under a comprehensive environment;

[0051] S500 , based on the electromechanical model of the motor in the comprehensive environment of ANSYS, insert a frequency response curve function to obtain the operating frequency and operating amplitude of the motor, insert an impedance curve function to obtain the voltage component impedance, and insert a node force function to obtain the stall torque.

[0052] Specifically, step S100 is as follows: in the Geometry function module, the motor housing and the stator assembly and rotor assembly inside the housing are established, and they are assembled according to the actual assembly method, such as Figure 2 and Figure 3 As shown, the stator assembly includes an elastic pad and piezoelectric ceramics, the rotor assembly includes a rotor disk and a friction material, and the teeth of the elastic pad are in contact with the friction material;

[0053] Step S200 specifically includes adding the materials and material properties required for the geometric model in the Engineering Data function module of ANSYS. For models to be used for thermal and mechanical analysis, the material properties should include density, elastic modulus, Poisson's ratio, thermal conductivity, and thermal expansion coefficient. The material property tables are shown in Tables 1 and 2:

[0054]

[0055] Table 1 Geometric model material properties

[0056]

[0057] Table 2 Anisotropic elastic constants of piezoelectric ceramics

[0058] Load the material properties of each part of the geometric model and the piezoelectric properties of the piezoelectric ceramics in the Model function module, and set the piezoelectric constant according to Table 3.

[0059]

[0060] Table 3 Piezoelectric parameters of piezoelectric ceramics

[0061] like Figure 4 As shown, the piezoelectric ceramics A and B respectively represent the positive and negative polarization regions in the z direction, and the positive polarization region and the negative polarization region of the piezoelectric ceramic are set in opposite directions;

[0062] The stator assembly and the rotor assembly are meshed, and constraint boundaries are set according to the actual installation method of the stator to complete the electromechanical model of the motor, which is used to output the working characteristics of the motor under actual conditions.

[0063] Step S300 specifically includes setting temperature parameters, random vibration parameters and centrifugal force parameters in ANSYS based on the motor electromechanical model, and outputting the temperature field, random vibration field and centrifugal force field of the motor during actual operation through the motor electromechanical model, wherein the temperature field includes coordinate data for characterizing the temperature distribution of the motor during operation and stress data for characterizing the temperature at each coordinate position, the random vibration field includes coordinate data for characterizing the vibration distribution of the motor during operation and stress data for characterizing the vibration at each coordinate position, and the centrifugal force field includes coordinate data for characterizing the centrifugal force distribution of the motor during operation and stress data for characterizing the centrifugal force at each coordinate position.

[0064] Step S400 is specifically as follows: outputting the temperature field, random vibration field and centrifugal force field in the form of Excel documents, selecting three data modules External Data based on ANSYS to read three Excel documents respectively, identifying the coordinate data and stress data of the temperature field, random vibration field and centrifugal force field in the three data modules respectively, adding the three data modules to the static analysis module of the motor electromechanical model, and using ANSYS's own function to load and update the static analysis module to realize the linear superposition of the temperature field, random vibration field and centrifugal force field, so that temperature, random vibration, and centrifugal force can be used as three different supplementary input parameters of the motor electromechanical model to obtain the motor electromechanical model under a comprehensive environment; by setting three different parameters, the input parameters of the motor electromechanical model are closer to the actual use scenario, thereby making the setting conditions of the input part more specific, and ensuring that the output characteristics are more in line with the actual use environment of the motor.

[0065] Step S500 is specifically as follows: in the electromechanical model of the motor under the comprehensive environment, adding the preload force under the actual working environment of the motor to the static analysis module, solving the static analysis module to obtain a second prestressed field caused by the preload force, adding the second prestressed field to the modal analysis module, solving the modal analysis module to obtain the modal vibration shape corresponding to the actual working state of the motor, adding the modal vibration shape to the harmonic response analysis module, inserting the frequency response curve function into a certain stator tooth surface in the harmonic response analysis module, and finding the first resonant frequency point with the same frequency as the modal vibration shape in the frequency response curve. The first resonant frequency point is a peak of the frequency response curve, and the frequency of the first resonant frequency point is the operating frequency of the motor. , which corresponds to the abscissa of the first resonant frequency point in the frequency response curve. At this time, the ordinate of the first resonant frequency point is the amplitude of the motor when it is actually working; in the harmonic response analysis module, insert the impedance curve function to the piezoelectric ceramic, and in the impedance curve, find the second resonant frequency point with the same operating frequency. The second resonant frequency point is a trough in the impedance curve, and the impedance corresponding to the second resonant frequency point is the voltage component impedance; in the harmonic response analysis module, insert the node force function to the contact pair of a stator tooth surface and the rotor. At the operating frequency, check the normal contact force result, adjust the phase angle, so that the target tooth surface is at the peak position. At this time, the normal contact force is the maximum, and calculate the stall torque T according to the following formula:

[0066] T=krμF max ,

[0067] Among them, k is the working wave number, r is the rotor radius, F max is the maximum normal contact force on the target stator tooth surface; thus, the complete output characteristics of the motor under comprehensive environment are obtained.

[0068] Working principle: by setting the motor electromechanical model, and setting the temperature parameters, random vibration parameters and centrifugal force parameters of the motor electromechanical model respectively, the motor temperature field, random vibration field and centrifugal stress field are simulated respectively, and three data modules are selected to read the temperature field, random vibration field and centrifugal force field respectively and add the data modules to the motor electromechanical model as parameter setting options of the model, which is equivalent to adding three restrictive conditions in different environments that can affect the output of the model to the motor electromechanical model, so that the model can obtain output characteristics under the influence of more environmental factors; inserting the frequency response curve function into the motor electromechanical model under the comprehensive environment can obtain the operating frequency and operating amplitude of the motor under actual operation, by inserting the impedance curve function, the voltage component impedance of the motor under actual operation can be obtained, and by inserting the node force function, the stall torque of the motor under actual operation can be obtained. By inserting the three functions, the motor electromechanical model under the comprehensive environment has more comprehensive output characteristics.

[0069] Furthermore, the method for obtaining the temperature field is:

[0070] Based on the electromechanical model of the motor, the heat loss of the motor in the working state is calculated. Specifically, the heat loss includes the structural loss of the piezoelectric ceramic and the dielectric loss P R , friction loss P at the contact surface between stator and rotor f , the structural loss P caused by stator vibration s , the heat loss is calculated by the following formula:

[0071]

[0072] T y =F n μ,

[0073] Among them, U is the motor input voltage, I is the motor input current, n is the motor speed, T2 is the output torque, T y is the preload torque, F n is the applied preload force, μ is the friction coefficient between the stator tooth surface and the rotor;

[0074] In the modal thermal analysis module of the motor electromechanical model, the P f The load of friction loss between the stator and rotor contact surface is directly applied to the friction material surface, and P R The first heat generation rate q R The load is added to the entire piezoelectric ceramic body, R The second heat generation rate q s The load is added to the stator as a whole, and the first heat generation rate q is calculated by the following formula R :

[0075] Among them, V R is the volume of piezoelectric ceramics;

[0076] The second heat generation rate q is calculated by the following formula s :

[0077] Among them, V s stator volume;

[0078] Complete the thermal boundary setting and solve the steady-state thermal analysis module, add the solution results to the static analysis module of the motor electromechanical model, apply the preload force during actual operation of the motor in the static analysis module, and solve the static analysis module to obtain the temperature field.

[0079] Furthermore, the steady-state thermal analysis module is modified through a temperature cycling test, specifically by:

[0080] A temperature cycling test is carried out on the motor in a temperature cycling chamber. The ambient temperature in the test chamber is set according to the actual operating temperature conditions of the motor. During the test, the motor is powered on and operates. After the temperature stabilizes, a first temperature of the motor housing, a second temperature of the internal environment of the housing, and an average temperature of three randomly selected test points on the side surface of the stator are obtained. The first temperature, the second temperature, and the average temperature are used to correct the steady-state thermal analysis module.

[0081] Furthermore, the method for obtaining the random vibration field is:

[0082] Based on the conditions of the motor electromechanical model, a preload force during actual operation of the motor is applied to a static analysis module of the motor electromechanical model, the static analysis module is solved to obtain a first prestress field caused by the preload force, the first prestress field is added to a modal analysis module of the motor electromechanical model, the modal analysis module is solved, the result of the modal analysis module is added to a random vibration analysis module of the motor electromechanical model, the vibration conditions during actual operation of the motor are added to the random vibration analysis module, and the random vibration analysis module is solved to obtain the random vibration field.

[0083] Furthermore, the method for obtaining the centrifugal force field is:

[0084] Based on the electromechanical model of the motor, the centrifugal force during actual operation of the motor is added to the static analysis module of the electromechanical model of the motor, and the centrifugal force field is obtained by solving the static analysis module.

[0085] The above description is merely a preferred embodiment of the present application and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of the invention herein is not limited to the technical solutions formed by the specific combination of the above-mentioned technical features, but also encompasses other technical solutions formed by any combination of the above-mentioned technical features or their equivalents without departing from the inventive concept. For example, a technical solution formed by replacing the above-mentioned features with (but not limited to) technical features having similar functions disclosed in this application.

Claims

1. The motor working state comprehensive environment reliability simulation method based on ANSYS is characterized by: The following steps are involved: S100, establish the geometric model of the motor stator assembly and rotor assembly based on ANSYS; S200, determining the materials of the stator assembly and the rotor assembly based on ANSYS, meshing the stator assembly and the rotor assembly respectively, loading and setting the piezoelectric properties of the piezoelectric ceramics and applying constraint boundaries to obtain an electromechanical model of the motor; S300, obtaining a temperature field, a random vibration field, and a centrifugal force field of the motor through the electromechanical model of the motor based on ANSYS, wherein the temperature field is used to characterize the temperature stress distribution of the motor, the random vibration field is used to characterize the random vibration distribution of the motor, and the centrifugal force field is used to characterize the centrifugal stress distribution of the motor; The method for obtaining the temperature field is: Calculating the heat loss of the motor in a working state based on the motor electromechanical model; Obtaining a thermal load at each position of the motor according to the heat loss, and applying the thermal load to a steady-state thermal analysis module of the motor electromechanical model; Setting a thermal boundary in the steady-state thermal analysis module; Solving the steady-state thermal analysis module and adding the results to the static analysis module, applying a preload in the static analysis module and solving to obtain the temperature field; The method for obtaining the random vibration field is: Applying a preload force in a static analysis module based on the motor electromechanical model, and solving the static analysis module to obtain a first prestress field caused by the preload force; Adding the first prestressed field to a modal analysis module and solving the modal analysis module; Adding the results of the modal analysis to a random vibration analysis module, and adding the vibration conditions of the motor during actual operation to the random vibration analysis module, solving the random vibration analysis module to obtain the random vibration field; The method for obtaining the centrifugal force field is: Based on the electromechanical model of the motor, the centrifugal force of the motor when actually working is added to the static analysis module, and the centrifugal force field is obtained by solving the static analysis module; S400, selecting three data modules based on ANSYS to read the temperature field, random vibration field, and centrifugal force field respectively, and adding the three data modules to the motor electromechanical model as parameter setting options of the model to obtain the motor electromechanical model under a comprehensive environment; S500 , based on the electromechanical model of the motor in the comprehensive environment of ANSYS, insert a frequency response curve function to obtain the operating frequency and operating amplitude of the motor, insert an impedance curve function to obtain the voltage component impedance, and insert a node force function to obtain the stall torque.

2. The motor working state comprehensive environment reliability simulation method based on ANSYS according to claim 1 is characterized in that: The formula for calculating the heat loss is as follows: T y =F n ·m, Among them, U is the motor input voltage, I is the motor input current, n is the motor speed, T2 is the output torque, T y is the preload torque, F n is the applied preload, μ is the friction coefficient between the stator tooth surface and the rotor, P R is the structural loss and dielectric loss of the piezoelectric ceramic, P f is the friction loss between the stator and rotor contact surface, P s is the loss within the structure caused by stator vibration.

3. The motor working state comprehensive environment reliability simulation method based on ANSYS according to claim 2 is characterized in that: The method of applying the thermal load is: In the steady-state analysis module, P f As a load applied to the surface of the friction material, P R The first heat generation rate q R The load is added to the entire piezoelectric ceramic body, R The second heat generation rate q s The load form is added to the stator as a whole, the first heat generation rate q R The calculation formula is as follows: Among them, V R is the volume of piezoelectric ceramics; The second heat generation rate q s The calculation formula is as follows: Among them, V s Stator volume.

4. The motor working state comprehensive environment reliability simulation method based on ANSYS according to claim 1 is characterized in that: Step S500 includes: Based on the electromechanical model of the motor in the comprehensive environment, the frequency response curve function of ANSYS is inserted into a certain stator tooth surface in the harmonic response analysis module to obtain the operating frequency and operating amplitude of the motor in the comprehensive environment, the impedance curve function of ANSYS is inserted into the piezoelectric ceramic to obtain the voltage component impedance of the motor, and the node force function of ANSYS is inserted into the contact pair of a certain stator tooth surface and the rotor to obtain the stall torque of the motor.

5. According to the ANSYS-based motor working state comprehensive environmental reliability simulation method according to claim 4, the calculation formula of the stall torque T is as follows: T=krμF max , in, k is the working wave number, r is the rotor radius, F max is the maximum normal contact force on the target stator tooth surface.

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