Torque pulsation optimization method and system of motor, electronic equipment and storage medium

Abstract

The invention provides a torque pulsation optimization method and system of a motor, electronic equipment and a storage medium, the motor comprises a rotor and a stator, and the torque pulsation optimization method is characterized in that the torque pulsation optimization method is used for simulation calculation of motor performance, and the torque pulsation optimization method comprises the following steps: adjusting a first geometric parameter of the rotor, the harmonic distortion rate of the no-load back electromotive force of the motor is smaller than a first distortion rate threshold value; adjusting a second geometric parameter of the stator to enable the phase and amplitude of the cogging torque of the motor to meet optimization conditions; and when the torque pulsating of the motor is smaller than a torque pulsating threshold value, taking the adjusted first geometric parameter and the adjusted second geometric parameter as target design parameters of the motor. According to the invention, the torque pulsating of the single-phase consequent-pole permanent magnet motor in the grid-connected state can be effectively suppressed, and the vibration and noise of the single-phase consequent-pole permanent magnet motor are reduced.

Description

Technical Field

[0001] The present disclosure relates to the field of motors, and in particular to a method, system, electronic device and storage medium for optimizing torque pulsation of a motor. Background Art

[0002] In order to improve the efficiency of the refrigerator compressor drive motor system, a single-phase permanent magnet motor system is applied to the refrigerator compressor motor system. However, when the single-phase permanent magnet motor is directly powered by a single-phase AC grid and runs in a grid-connected state, the motor speed is the synchronous speed, and the motor torque pulsation is usually greater than 200%. The torque pulsation is too large, which leads to greater vibration and noise in the motor. This will cause a bad experience during the use of the refrigerator. Summary of the invention

[0003] The problem to be solved by the present disclosure is to overcome the defect in the prior art that the torque pulsation of a single-phase permanent magnet motor is too large when the motor is directly powered by a single-phase AC power grid, and to provide a method, system, electronic device and storage medium for optimizing the torque pulsation of a motor.

[0004] The present invention solves the above technical problems through the following technical solutions:

[0005] The present disclosure provides a method for optimizing torque pulsation of a motor, wherein the motor includes a rotor and a stator. The method for optimizing torque pulsation is used for simulating and calculating motor performance. The method for optimizing torque pulsation includes:

[0006] Adjusting a first geometric parameter of the rotor so that a harmonic distortion rate of a no-load back electromotive force of the motor is less than a first distortion rate threshold;

[0007] Adjusting the second geometric parameter of the stator so that the phase and amplitude of the cogging torque of the motor meet the optimization condition;

[0008] When the torque pulsation of the motor is less than a torque pulsation threshold, the adjusted first geometric parameter and the adjusted second geometric parameter are used as target design parameters of the motor.

[0009] Preferably, after the step of adjusting the second geometric parameter of the stator so that the phase and amplitude of the cogging torque of the motor meet the optimization condition, the method further comprises:

[0010] The first geometric parameter of the rotor is adjusted so that the harmonic distortion rate of the no-load back electromotive force of the motor is less than a second distortion rate threshold.

[0011] Preferably, the optimization condition includes at least one of the following:

[0012] The peak value of the cogging torque is less than or equal to a torque threshold; the torque threshold is determined by the electromagnetic torque of the motor in the current optimization stage;

[0013] The phase difference between the crest of the cogging torque and the trough of the current electromagnetic torque of the motor is less than a first phase difference threshold, or the phase difference between the trough of the cogging torque and the crest of the current electromagnetic torque of the motor is less than a second phase difference threshold.

[0014] Preferably, the rotor comprises an iron core and a permanent magnet, the iron core and the permanent magnet form a protrusion on the outer edge of the rotor, and the outer edge of the section of the protrusion is an arc; the first geometric parameter of the rotor is adjusted so that the harmonic distortion rate of the no-load back electromotive force of the motor is less than a first distortion rate threshold, comprising:

[0015] By adjusting the curvature of the outer edge of the iron core, the eccentricity of the iron core is changed;

[0016] By adjusting the curvature of the outer edge of the permanent magnet, the eccentricity of the permanent magnet is changed;

[0017] Determining the harmonic distortion rate of the current no-load back electromotive force of the motor;

[0018] If the harmonic distortion rate is less than a first distortion rate threshold, the current first geometric parameter is used as a first target design parameter of the rotor.

[0019] Preferably, the stator includes a tooth tip portion; the second geometric parameter includes an inner diameter of the tooth tip; and adjusting the second geometric parameter of the stator so that the phase and amplitude of the cogging torque of the motor meet the optimization condition comprises:

[0020] The phase and amplitude of the cogging torque of the motor are changed by adjusting the inner diameter of the tooth tip of the tooth tip portion; the inner diameter of the tooth tip is the distance from the tooth tip portion to the center of the rotating shaft of the rotor;

[0021] If the phase and amplitude of the cogging torque of the motor meet the optimization conditions, the current second geometric parameter is used as the second target design parameter of the stator.

[0022] Preferably, the step of adjusting the inner diameter of the tooth tip of the tooth tip portion to change the phase and amplitude of the cogging torque of the motor comprises:

[0023] If the rotation direction of the rotor is clockwise, the inner diameter of the tooth tip is gradually reduced in the clockwise direction;

[0024] If the rotation direction of the rotor is counterclockwise, the inner diameter of the tooth tip is gradually reduced in the counterclockwise direction.

[0025] The present disclosure also provides a torque pulsation optimization system for a motor, wherein the motor includes a rotor and a stator, and is characterized in that the torque pulsation optimization system is used for simulation calculation of motor performance, and the torque pulsation optimization system includes:

[0026] An adjustment module, used for adjusting a first geometric parameter of the rotor so that a harmonic distortion rate of a no-load back electromotive force of the motor is less than a first distortion rate threshold;

[0027] The adjustment module is further used to adjust the second geometric parameter of the stator so that the phase and amplitude of the cogging torque of the motor meet the optimization conditions;

[0028] The parameter determination module is used to use the adjusted first geometric parameter and the adjusted second geometric parameter as target design parameters of the motor when the torque pulsation of the motor is less than a torque pulsation threshold.

[0029] Preferably, the adjustment module is further used to adjust the first geometric parameter of the rotor so that the harmonic distortion rate of the no-load back electromotive force of the motor is less than a second distortion rate threshold.

[0030] Preferably, the optimization condition includes at least one of the following:

[0031] The peak value of the cogging torque is less than or equal to a torque threshold; the torque threshold is determined by the electromagnetic torque of the motor in the current optimization stage;

[0032] The phase difference between the crest of the cogging torque and the trough of the current electromagnetic torque of the motor is less than a first phase difference threshold, or the phase difference between the trough of the cogging torque and the crest of the current electromagnetic torque of the motor is less than a second phase difference threshold.

[0033] Preferably, the rotor comprises an iron core and a permanent magnet, the iron core and the permanent magnet form a protrusion on the outer edge of the rotor, and the outer edge of the section of the protrusion is an arc; the adjustment module comprises:

[0034] A first adjustment unit, used to change the eccentricity of the iron core by adjusting the curvature of the outer edge of the iron core;

[0035] The first adjustment unit is further used to change the eccentricity of the permanent magnet by adjusting the curvature of the outer edge of the permanent magnet;

[0036] A first determining unit, used to determine the harmonic distortion rate of the current no-load back electromotive force of the motor;

[0037] The first parameter determination unit is used to use the current first geometric parameter as the first target design parameter of the rotor if the harmonic distortion rate is less than a first distortion rate threshold.

[0038] Preferably, the stator includes a tooth tip portion; the second geometric parameter includes an inner diameter of the tooth tip; and the adjustment module includes:

[0039] a second adjustment unit, configured to change the phase and amplitude of the cogging torque of the motor by adjusting the inner diameter of the tooth tip of the tooth tip portion; the inner diameter of the tooth tip being the distance from the tooth tip portion to the center of the rotating shaft of the rotor;

[0040] The second parameter determination unit is used to use the current second geometric parameter as the second target design parameter of the stator if the phase and amplitude of the cogging torque of the motor meet the optimization conditions.

[0041] Preferably, the second adjustment unit is specifically configured to include:

[0042] If the rotation direction of the rotor is clockwise, the inner diameter of the tooth tip is gradually reduced in the clockwise direction;

[0043] If the rotation direction of the rotor is counterclockwise, the inner diameter of the tooth tip is gradually reduced in the counterclockwise direction.

[0044] The present disclosure also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and used to run on the processor, and the processor implements the aforementioned torque pulsation optimization method of the motor when executing the computer program.

[0045] The present disclosure also provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the aforementioned method for optimizing the torque pulsation of the motor is implemented.

[0046] On the basis of being in accordance with the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present disclosure.

[0047] The positive and progressive effect of the present disclosure is that: by adjusting the first geometric parameter of the rotor so that the harmonic distortion rate of the no-load back electromotive force of the motor is less than the first distortion rate threshold; and adjusting the second geometric parameter of the stator so that the phase and amplitude of the cogging torque of the motor meet the optimization conditions; finally, the first geometric parameter and the second geometric parameter of the motor whose torque pulsation is less than the torque pulsation threshold are used as the target design parameters for torque pulsation optimization. The torque pulsation of the single-phase alternating pole permanent magnet motor in the grid-connected state can be effectively suppressed, and the vibration and noise of the single-phase alternating pole permanent magnet motor can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 A flowchart of a method for optimizing torque pulsation of a motor provided by an exemplary embodiment of the present disclosure.

[0049] Figure 2A schematic diagram of the structure of a motor provided by an exemplary embodiment of the present disclosure.

[0050] Figure 3 A flowchart of step 101 is provided for an exemplary embodiment of the present disclosure.

[0051] Figure 4 A schematic diagram of a rotor structure of a motor provided by an exemplary embodiment of the present disclosure

[0052] Figure 5 A torque waveform schematic diagram provided for an exemplary embodiment of the present disclosure.

[0053] Figure 6 A flowchart of step 102 is provided for an exemplary embodiment of the present disclosure.

[0054] Figure 7 A schematic diagram of the structure of another motor provided by an exemplary embodiment of the present disclosure.

[0055] Figure 8 A schematic diagram of a tooth tip portion of a stator provided according to an exemplary embodiment of the present disclosure.

[0056] Fig. 9 A flowchart of another method for optimizing torque pulsation of a motor provided by an exemplary embodiment of the present disclosure.

[0057] Fig.10 A waveform diagram of a no-load back electromotive force is provided for an exemplary embodiment of the present disclosure.

[0058] Fig.11 Another torque waveform schematic diagram provided for an exemplary embodiment of the present disclosure.

[0059] Fig.12 A waveform diagram of a cogging torque provided for an exemplary embodiment of the present disclosure.

[0060] Fig.13 A waveform diagram of another no-load back electromotive force provided for an exemplary embodiment of the present disclosure.

[0061] Fig.14 A waveform diagram of another no-load back electromotive force provided for an exemplary embodiment of the present disclosure.

[0062] Fig.15 , which is a module schematic diagram of a torque pulsation optimization system for a motor provided by an exemplary embodiment of the present disclosure.

[0063] Fig.16 The present invention provides a schematic structural diagram of an electronic device according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0064] The present disclosure is further described below by way of examples, but the present disclosure is not limited to the scope of the examples.

[0065] The embodiments involved in the present disclosure are used for optimizing the performance of motors, and in particular, for optimizing the torque pulsation of motors. Specifically, the present disclosure is dedicated to minimizing the torque pulsation of motors when they are connected to the grid, and avoiding the negative effects caused by excessive torque pulsation. For example, in the field of household appliances, the single-phase permanent magnet motors that drive the compressors in some refrigerators can be switched to the grid-connected state, that is, when they are directly powered by a single-phase AC grid, the motor speed is the synchronous speed, and the torque pulsation of the motor is usually greater than 200%. Since the torque pulsation is too large, the motor will have greater vibration and noise. Among them, the specific technical means for optimizing the torque pulsation can be iteratively optimized through the computer simulation software used in existing industrial design, or calculated and optimized through other automated tools that can perform theoretical calculations.

[0066] It should be understood that the technical means involved in the present disclosure can be applicable to single-phase permanent magnet motors, and can also involve single-phase permanent magnet motors with other different rotor topologies (for example, single-phase permanent magnet motors such as surface-mounted / alternating pole / Halbach array). Any motor that meets the implementation requirements of the present disclosure in terms of mechanical structure and / or working principle can implement the embodiments involved in the present disclosure.

[0067] Example 1

[0068] Figure 1 A flowchart of a method for optimizing torque pulsation of a motor provided by an exemplary embodiment of the present disclosure, wherein the motor includes a rotor and a stator, for example, see Figure 2 A schematic diagram of the structure of a motor provided for an exemplary embodiment of the present disclosure, from which it can be known that the motor includes: a stator core 11, a rotor core 12, a permanent magnet 13, a winding 14 and a rotating shaft 15, wherein the stator core 11 is a part of the stator, and the rotor core 12, the permanent magnet 13 and the rotating shaft 15 are a part of the rotor. The torque pulsation optimization method is used for simulation calculation of motor performance. Therefore, it should be understood that the motor involved in the embodiment and the components included in the motor (such as the stator and the rotor) can be a digital model constructed for simulation calculation. The torque pulsation optimization method of the motor includes the following steps:

[0069] Step 101: Adjust a first geometric parameter of the rotor so that the harmonic distortion rate of the no-load back electromotive force of the motor is less than a first distortion rate threshold.

[0070] Among them, the first geometric parameters are design parameters for the rotor, including but not limited to the following: eccentricity, pole arc coefficient, thickness, width, magnetization method, magnetization angle of the permanent magnet and the eccentricity, pole arc coefficient, thickness, width of the ferromagnetic pole and auxiliary grooves on the surface of the rotor core, construction of uneven air gap, etc.

[0071] Optionally, the calculation method of the harmonic distortion rate of the no-load back electromotive force can be calculated by the following formula:

[0072]

[0073] Where THD is the harmonic distortion rate of the no-load back EMF, V1 is the fundamental amplitude of the no-load back EMF, V n is the amplitude of the nth harmonic of the no-load back EMF, where n is a positive integer greater than or equal to 1.

[0074] The basic basis of this step is to make the no-load potential waveform of the motor close to sine without considering the starting ability of the motor. For example, the eccentricity of the permanent magnet poles and the ferromagnetic poles of the motor is optimized to make the no-load back EMF of the motor as close to sine as possible, and the smaller the harmonic distortion rate, the better; and the cogging torque is zero at the dead point of the motor (when the axis of the magnetic pole is aligned with the center line of the stator teeth), and the period of the cogging torque is the time corresponding to the rotor rotating one stator tooth pitch.

[0075] Optionally, the rotor includes an iron core and a permanent magnet, the iron core and the permanent magnet form a protrusion on the outer edge of the rotor, and the outer edge of the section of the protrusion is an arc. Figure 3 Step 101 includes:

[0076] Step 1011: Change the eccentricity of the iron core by adjusting the curvature of the outer edge of the iron core.

[0077] Step 1012: Change the eccentricity of the permanent magnet by adjusting the outer edge curvature of the permanent magnet.

[0078] Step 1013: Determine the harmonic distortion rate of the current no-load back electromotive force of the motor.

[0079] Step 1014: If the harmonic distortion rate is less than the first distortion rate threshold, the current first geometric parameter is used as the first target design parameter of the rotor.

[0080] See also Figure 4 This is a schematic diagram of the structure of a rotor of a motor provided by an exemplary embodiment of the present disclosure, from which it can be known that the rotor includes a permanent magnet 13 and a ferromagnetic pole 16. Among them, the center O1 corresponding to the outer arc of the permanent magnet shown in the figure is not at the center of the rotor, and the distance O1O is called the eccentricity of the permanent magnet, represented by h1, and the center O2 corresponding to the outer arc of the ferromagnetic pole is not at the rotor origin O, and the distance O2O is called the eccentricity of the ferromagnetic pole, represented by h2.

[0081] Step 102: Adjust the second geometric parameter of the stator so that the phase and amplitude of the cogging torque of the motor meet the optimization conditions.

[0082] Among them, the second geometric parameters are design parameters for the stator, including but not limited to the following: tooth tip inner diameter, tooth tip chamfer, stator auxiliary slots, stator auxiliary teeth, length, diameter, radius, width, eccentricity, etc.

[0083] Optionally, the optimization condition includes at least one of the following:

[0084] Condition 1: The peak value of the cogging torque is less than or equal to the torque threshold; the torque threshold is determined by the electromagnetic torque of the motor in the current optimization stage.

[0085] Optionally, in a specific implementation, the torque threshold may be determined based on the average value of the electromagnetic torque, for example, the average value of the electromagnetic torque is multiplied by a% to obtain the torque threshold, where a is a value preset by the designer, and 0≤a≤100. The specific value of a may be adjusted according to actual needs.

[0086] Condition 2: the phase difference between the crest of the cogging torque and the trough of the current electromagnetic torque of the motor is less than the first phase difference threshold, or the phase difference between the trough of the cogging torque and the crest of the current electromagnetic torque of the motor is less than the second phase difference threshold.

[0087] For condition 2, optionally, in a specific implementation, the first phase difference threshold is 45 degrees (electrical angle), and the second phase difference threshold is 45 degrees (electrical angle). Figure 5 It can be seen that T3 is the torque of the motor (represented by a solid line in the figure), Tem3 is the electromagnetic torque (represented by a short dashed line in the figure), and Tc3 is the cogging torque (represented by a dotted line in the figure). It can be seen that the phase between the peak of the electromagnetic torque and the trough of the cogging torque does not exceed 45 degrees, and the waveform of the torque of the motor generated by the superposition of the two is relatively stable. Therefore, the torque pulsation at this time is small. Among them, the first phase difference threshold and the second phase difference threshold can be adjusted according to actual needs. Preferably, the smaller the first phase difference threshold and the second phase difference threshold, the better.

[0088] It should be understood that, in theory, in order to minimize the waveform of the torque pulsation, the phase difference between the electromagnetic torque and the cogging torque can be made 90 degrees, that is, the peak of the cogging torque corresponds to the trough of the current electromagnetic torque of the motor, or the trough of the cogging torque corresponds to the peak of the current electromagnetic torque of the motor. This will better offset the two waveforms to achieve a relatively smooth waveform of the torque of the motor resulting from the superposition of the two waveforms.

[0089] Optionally, the stator includes a tooth tip portion; the second geometric parameter includes an inner diameter of the tooth tip; see Figure 6 Step 102 includes:

[0090] Step 1021, changing the phase and amplitude of the cogging torque of the motor by adjusting the inner diameter of the tooth tip; the inner diameter of the tooth tip is the distance from the tooth tip part to the center of the rotating shaft of the rotor.

[0091] Optionally, step 1021 specifically includes at least the following two situations:

[0092] Case 1: If the rotor rotates clockwise, the inner diameter of the tooth tip is gradually reduced in the clockwise direction.

[0093] Case 2: If the rotor rotates counterclockwise, the inner diameter of the tooth tip is gradually reduced in the counterclockwise direction.

[0094] It should be understood that the above situations 1 and 2 are only representative examples. When the motor is working, the rotor generally has two running directions, clockwise and counterclockwise. The present disclosure is set specifically for different application scenarios. For example, Figure 7 As shown in the figure, when the motor is set to rotate counterclockwise, the inner diameter of the tooth tip is gradually reduced in the counterclockwise direction. It can be seen from the figure that the central angle θ AB Tooth tip inner diameter R A to R B gradually decreases during the process.

[0095] In a specific embodiment, see Figure 8 It can be seen that arc DE is the edge of the stator tooth tip facing the rotor. Taking case 2 as an example, if the rotor rotates counterclockwise, the inner diameter of the tooth tip is gradually reduced in the counterclockwise direction. The specific method is to use point D as the center of the circle and rotate arc DE counterclockwise by a certain angle (the angle adjustment step can be set according to actual needs, for example, the step is 0.01 degrees) to rotate to arc DF ( Figure 8 After confirming the arc DE and the arc DF, the part between the arc DE and the arc DF is deleted, and the remaining part is the adjusted tooth tip part, which will form a shape in which the inner diameter of the tooth tip gradually decreases in the counterclockwise direction. Similarly, case 1 can also refer to the above steps. With point E as the center of the circle, after rotating the arc DE clockwise for a certain angle, the part between the two arcs is deleted, and no further details are given here. It should be understood that the arc DF is not necessarily generated based on the arc DE, and any arc DF can be generated according to actual needs.

[0096] Step 1022: If the phase and amplitude of the cogging torque of the motor meet the optimization conditions, the current second geometric parameter is used as the second target design parameter of the stator.

[0097] Step 103: When the torque pulsation of the motor is less than the torque pulsation threshold, the adjusted first geometric parameter and the adjusted second geometric parameter are used as target design parameters of the motor.

[0098] In this step, if the conditions required in this step are met through steps 101 and 102: when the torque pulsation of the motor is less than the torque pulsation threshold, the adjusted first geometric parameter and the adjusted second geometric parameter are used as the target design parameters of the motor. It should be understood that before executing step 103, steps 101 and 102 can be repeatedly executed according to actual needs to achieve iterative optimization and finally complete step 103.

[0099] Optionally, refer to Fig. 9 It can be seen that after step 102, the following steps are also included:

[0100] Step 104: Adjust the first geometric parameter of the rotor so that the harmonic distortion rate of the no-load back electromotive force of the motor is less than a second distortion rate threshold.

[0101] In this step, it is a supplementary step after step 102, and its purpose is to repair the waveform of the no-load back electromotive force that has changed in step 102. Specifically, since the second geometric parameter of the stator is adjusted in step 102 (for example, the inner diameter of the tooth tip of the tooth tip part of the stator is adjusted), the waveform of the no-load back electromotive force will change, that is, the original waveform that is close to sine is destroyed (the harmonic distortion rate of the no-load back electromotive force becomes larger), so in this step, the first geometric parameter of the rotor is re-adjusted to make the harmonic distortion rate of the no-load back electromotive force of the motor less than the second distortion rate threshold, so as to achieve the harmonic distortion rate of the no-load back electromotive force close to sine again. This is conducive to making the optimization result more in line with expectations.

[0102] Then, if the condition required in step 103 is met through steps 101, 102 and 104: when the torque pulsation of the motor is less than the torque pulsation threshold, the adjusted first geometric parameter and the adjusted second geometric parameter are used as the target design parameters of the motor. It should be understood that before executing step 103, steps 101, 102 and step 104 can be repeatedly executed according to actual needs to achieve iterative optimization and finally complete step 103.

[0103] To further illustrate the above embodiment, a specific example is given here:

[0104] In this example, a single-phase alternating-pole permanent magnet motor used in a refrigerator compressor is used as an example. Figure 2As shown. Among them, the protruding part of the rotor core is the equivalent ferromagnetic pole. The permanent magnet is installed on the surface of the rotor core, the magnetization direction of the permanent magnet is radial magnetization, the number of stator slots is 6, and the grid-connected speed is 1000rpm. The frequency of the single-phase AC power grid is 50Hz, and the effective value of the voltage is 220V. Without considering the starting performance of the motor, when the eccentricity of the permanent magnet and the ferromagnetic pole is zero, the no-load back EMF of the motor contains large 3rd, 5th, 7th and other harmonics.

[0105] First, the permanent magnet eccentricity h1 and the ferromagnetic pole eccentricity h2 are optimized to make the no-load back EMF of the motor sinusoidal and its harmonic distortion rate minimum. After optimization, h1 is 6mm and h2 is 14mm. The optimized no-load back EMF E1 is as follows: Fig.10 As shown in the figure, its harmonic distortion rate is 2.4%. When the single-phase AC power grid is used for power supply, the motor torque T1 (indicated by the solid line in the figure), the electromagnetic torque Te1 (indicated by the short dashed line in the figure), and the cogging torque Tc1 (indicated by the dotted line in the figure) are as follows: Fig.11 As shown, the average value of the grid-connected torque is 150 mNm, the peak-to-peak value is 284 mNm, and the pulsation is 189%.

[0106] Then, the tooth tip of the motor stator is processed so that the center angle θ corresponding to the tooth tip is AB The inner diameter of the motor in the range gradually decreases in the counterclockwise direction, such as Figure 7 As shown, the inner diameter of the stator at point A is R A The inner diameter of the motor at point B is 58.2 mm. B The inner diameter of the motor stator is 55 mm. The inner diameter of the motor stator gradually decreases from point A to point B. All stator tooth tips are treated in the same way. The toothing torque Tc2 and the no-load back EMF E2 are as follows: Fig.12 , Fig.13 As shown. The cogging torque is close to the maximum value at the motor dead point, and its value is 101mNm, R A and R B The greater the difference, the greater the maximum value of the motor's cogging torque. The harmonic distortion rate of the no-load back EMF E2 is 10.5%, which is a relatively large value.

[0107] Next, keep the stator side size unchanged and re-optimize the permanent magnet eccentricity h1 and the ferromagnetic pole eccentricity h2 to make the no-load back EMF of the motor as close to sine as possible. After optimization, h1 is 6mm and h2 is 5.9mm. The optimized no-load back EMF E3 is as follows: Fig.14 As shown, its harmonic distortion rate is 4.5%.

[0108] When the single-phase AC power grid is used for power supply, the torque T3, electromagnetic torque Tem3 and cogging torque Tc3 of the single-phase alternating pole permanent magnet motor are as follows: Figure 5As shown. The maximum value of the cogging torque corresponds to the minimum value of the electromagnetic torque, and the minimum value of the cogging torque corresponds to the maximum value of the electromagnetic torque. The maximum value of the cogging torque is 120mNm, the average value of the grid-connected torque is 151mNm, the peak-to-peak value is 85mNm, and the pulsation is 56%. The minimum value of the motor torque is 121mNm, and the motor starting ability is enhanced.

[0109] The torque pulsation optimization method can effectively suppress the torque pulsation of the single-phase alternating-pole permanent magnet motor in the grid-connected state, and reduce the vibration and noise of the single-phase alternating-pole permanent magnet motor.

[0110] Example 2

[0111] Reference Fig.15 , is a schematic diagram of a module of a torque pulsation optimization system for a motor provided by an exemplary embodiment of the present disclosure, wherein the torque pulsation optimization system for the motor corresponds to a torque pulsation optimization method for the motor. The motor includes a rotor and a stator, and is characterized in that the torque pulsation optimization system is used for simulation calculation of motor performance, and the torque pulsation optimization system includes:

[0112] An adjustment module 21, used for adjusting a first geometric parameter of the rotor so that a harmonic distortion rate of a no-load back electromotive force of the motor is less than a first distortion rate threshold;

[0113] The adjustment module 21 is further used to adjust the second geometric parameter of the stator so that the phase and amplitude of the cogging torque of the motor meet the optimization conditions;

[0114] The parameter determination module 22 is used to use the adjusted first geometric parameter and the adjusted second geometric parameter as target design parameters of the motor when the torque pulsation of the motor is less than the torque pulsation threshold.

[0115] Optionally, the adjustment module 21 is further configured to adjust a first geometric parameter of the rotor so that a harmonic distortion rate of a no-load back electromotive force of the motor is less than a second distortion rate threshold.

[0116] Optionally, the optimization condition includes at least one of the following:

[0117] The peak value of the cogging torque is less than or equal to the torque threshold; the torque threshold is determined by the electromagnetic torque of the motor in the current optimization stage;

[0118] The phase difference between the crest of the cogging torque and the trough of the current electromagnetic torque of the motor is less than the first phase difference threshold, or the phase difference between the trough of the cogging torque and the crest of the current electromagnetic torque of the motor is less than the second phase difference threshold.

[0119] Optionally, the rotor includes an iron core and a permanent magnet, the iron core and the permanent magnet form a protrusion on the outer edge of the rotor, and the outer edge of the section of the protrusion is an arc; the adjustment module 21 includes:

[0120] A first adjustment unit is used to change the eccentricity of the iron core by adjusting the curvature of the outer edge of the iron core;

[0121] The first adjustment unit is further used to change the eccentricity of the permanent magnet by adjusting the curvature of the outer edge of the permanent magnet;

[0122] A first determining unit, used to determine the harmonic distortion rate of the current no-load back electromotive force of the motor;

[0123] The first parameter determination unit is used to use the current first geometric parameter as the first target design parameter of the rotor if the harmonic distortion rate is less than a first distortion rate threshold.

[0124] Optionally, the stator includes a tooth tip portion; the second geometric parameter includes an inner diameter of the tooth tip; and the adjustment module 21 includes:

[0125] The second adjustment unit is used to change the phase and amplitude of the cogging torque of the motor by adjusting the inner diameter of the tooth tip of the tooth tip part; the inner diameter of the tooth tip is the distance from the tooth tip part to the center of the rotating shaft of the rotor;

[0126] The second parameter determination unit is used to use the current second geometric parameter as the second target design parameter of the stator if the phase and amplitude of the cogging torque of the motor meet the optimization conditions.

[0127] Optionally, the second adjustment unit is specifically configured to include:

[0128] If the rotor rotates clockwise, the inner diameter of the tooth tip is gradually reduced in the clockwise direction;

[0129] If the rotation direction of the rotor is counterclockwise, the inner diameter of the tooth tip is gradually reduced in the counterclockwise direction.

[0130] The torque pulsation optimization system can effectively suppress the torque pulsation of the single-phase alternating-pole permanent magnet motor in the grid-connected state, and reduce the vibration and noise of the single-phase alternating-pole permanent magnet motor.

[0131] Example 3

[0132] Fig.16 The present invention provides a schematic diagram of the structure of an electronic device provided in this embodiment. The electronic device includes a memory, a processor, and a computer program stored in the memory and used to run on the processor, and when the processor executes the program, the torque pulsation optimization method of the motor provided in any of the above embodiments is implemented. Fig.16 The electronic device 300 shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present disclosure.

[0133] Reference Fig.16The electronic device 300 may be in the form of a general-purpose computing device, for example, it may be a server device. The components of the electronic device 300 may include, but are not limited to: at least one processor 301, at least one memory 302, and a bus 303 connecting different system components (including the memory 302 and the processor 301).

[0134] The bus 303 includes a data bus, an address bus, and a control bus.

[0135] The memory 302 may include a volatile memory, such as a random access memory (RAM) 321 and / or a cache memory 322 , and may further include a read-only memory (ROM) 323 .

[0136] Memory 302 may also include a program / utility 325 having a set (at least one) of program modules 324, such program modules 324 including but not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment.

[0137] The processor 301 executes various functional applications and data processing by running the computer program stored in the memory 302, such as the torque pulsation optimization method of the motor according to the embodiment of the present disclosure.

[0138] The electronic device 300 may also communicate with one or more external devices 304 (e.g., keyboards, pointing devices, etc.). Such communication may be performed via an input / output (I / O) interface 305. Furthermore, the model-generated device 300 may also communicate with one or more networks (e.g., a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) via a network adapter 306. As shown, the network adapter 306 communicates with other modules of the model-generated device 300 via a bus 303. It should be understood that, although not shown in the figure, other hardware and / or software modules may be used in conjunction with the model-generated device 300, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID (RAID) systems, tape drives, and data backup storage systems, etc.

[0139] It should be noted that although several units / modules or sub-units / modules of the electronic device are mentioned in the above detailed description, this division is merely exemplary and not mandatory. In fact, according to the embodiments of the present disclosure, the features and functions of two or more units / modules described above can be embodied in one unit / module. Conversely, the features and functions of one unit / module described above can be further divided into multiple units / modules to be embodied.

[0140] Example 4

[0141] This embodiment further provides a computer-readable storage medium having a computer program stored thereon, and when the program is executed by a processor, the method for optimizing the torque pulsation of a motor provided in any of the above embodiments is implemented.

[0142] The readable storage medium may include but is not limited to: a portable disk, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory, an optical storage device, a magnetic storage device or any suitable combination of the above.

[0143] In a possible implementation, the present disclosure may also be implemented in the form of a program product, which includes a program code. When the program product is run on a terminal device, the program code is used to enable the terminal device to execute the torque pulsation optimization method for the motor provided in any of the above embodiments.

[0144] Among them, the program code for executing the present disclosure can be written in any combination of one or more programming languages, and the program code can be executed completely on the user device, partially on the user device, as an independent software package, partially on the user device and partially on a remote device, or completely on the remote device.

[0145] Although the specific embodiments of the present disclosure are described above, those skilled in the art should understand that this is only an example, and the protection scope of the present disclosure is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present disclosure, but these changes and modifications all fall within the protection scope of the present disclosure.

Claims

1. A method for optimizing torque pulsation of a motor, the motor comprising a rotor and a stator, characterized in that: The torque pulsation optimization method is used for simulation calculation of motor performance, and the torque pulsation optimization method includes: Adjusting a first geometric parameter of the rotor so that a harmonic distortion rate of a no-load back electromotive force of the motor is less than a first distortion rate threshold; Adjusting the second geometric parameter of the stator so that the phase and amplitude of the cogging torque of the motor meet the optimization condition; When the torque pulsation of the motor is less than a torque pulsation threshold, the adjusted first geometric parameter and the adjusted second geometric parameter are used as target design parameters of the motor.

2. The method for optimizing the torque pulsation of a motor according to claim 1, characterized in that: After the step of adjusting the second geometric parameter of the stator so that the phase and amplitude of the cogging torque of the motor meet the optimization condition, the method further includes: The first geometric parameter of the rotor is adjusted so that the harmonic distortion rate of the no-load back electromotive force of the motor is less than a second distortion rate threshold.

3. The method for optimizing the torque pulsation of a motor according to claim 1, characterized in that: The optimization condition includes at least one of the following: The peak value of the cogging torque is less than or equal to a torque threshold; the torque threshold is determined by the electromagnetic torque of the motor in the current optimization stage; The phase difference between the crest of the cogging torque and the trough of the current electromagnetic torque of the motor is less than a first phase difference threshold, or the phase difference between the trough of the cogging torque and the crest of the current electromagnetic torque of the motor is less than a second phase difference threshold.

4. The method for optimizing the torque pulsation of a motor according to any one of claims 1 to 3, characterized in that: The rotor includes an iron core and a permanent magnet, the iron core and the permanent magnet form a protrusion on the outer edge of the rotor, and the outer edge of the section of the protrusion is an arc; the first geometric parameter of the rotor is adjusted so that the harmonic distortion rate of the no-load back electromotive force of the motor is less than a first distortion rate threshold, including: By adjusting the curvature of the outer edge of the iron core, the eccentricity of the iron core is changed; By adjusting the curvature of the outer edge of the permanent magnet, the eccentricity of the permanent magnet is changed; Determining the harmonic distortion rate of the current no-load back electromotive force of the motor; If the harmonic distortion rate is less than a first distortion rate threshold, the current first geometric parameter is used as a first target design parameter of the rotor.

5. The method for optimizing the torque pulsation of a motor according to any one of claims 1 to 3, characterized in that: The stator includes a tooth tip portion; the second geometric parameter includes an inner diameter of the tooth tip; and the second geometric parameter of the stator is adjusted so that the phase and amplitude of the cogging torque of the motor meet the optimization condition, including: The phase and amplitude of the cogging torque of the motor are changed by adjusting the inner diameter of the tooth tip of the tooth tip portion; the inner diameter of the tooth tip is the distance from the tooth tip portion to the center of the rotating shaft of the rotor; If the phase and amplitude of the cogging torque of the motor meet the optimization conditions, the current second geometric parameter is used as the second target design parameter of the stator.

6. The method for optimizing the torque pulsation of a motor according to claim 5, characterized in that: The method of changing the phase and amplitude of the cogging torque of the motor by adjusting the inner diameter of the tooth tip of the tooth tip portion comprises: If the rotation direction of the rotor is clockwise, the inner diameter of the tooth tip is gradually reduced in the clockwise direction; If the rotation direction of the rotor is counterclockwise, the inner diameter of the tooth tip is gradually reduced in the counterclockwise direction.

7. A torque pulsation optimization system for a motor, the motor comprising a rotor and a stator, characterized in that: The torque pulsation optimization system is used for simulation calculation of motor performance, and the torque pulsation optimization system includes: An adjustment module, used for adjusting a first geometric parameter of the rotor so that a harmonic distortion rate of a no-load back electromotive force of the motor is less than a first distortion rate threshold; The adjustment module is further used to adjust the second geometric parameter of the stator so that the phase and amplitude of the cogging torque of the motor meet the optimization conditions; The parameter determination module is used to use the adjusted first geometric parameter and the adjusted second geometric parameter as target design parameters of the motor when the torque pulsation of the motor is less than a torque pulsation threshold.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and used to run on the processor, characterized in that: When the processor executes the computer program, the torque pulsation optimization method of the motor according to any one of claims 1 to 6 is implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the torque pulsation optimization method of the motor according to any one of claims 1 to 6 is implemented.

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