Method and device for improving output linearity of permanent magnet motor, computer and medium

Abstract

The application provides a method and device for improving the linearity of a permanent magnet motor, a computer and a medium, which comprises inputting a preset current value into the permanent magnet motor; measuring the displacement information of the mover of the permanent magnet motor; substituting the preset current value and the displacement information into a preset motor dynamics model to obtain a corrected electromagnetic force coefficient; substituting the corrected electromagnetic force coefficient and a target output power into the preset motor dynamics model to calculate an output current value; and inputting the output current value into the permanent magnet motor. The preset current value input into the permanent magnet motor and the displacement information of the mover measured in real time are input into the preset motor dynamics model to correct the electromagnetic force coefficient, so that an accurate electromagnetic force coefficient is obtained. The corrected electromagnetic force coefficient and the target output power are input into the motor dynamics model, so that the output power generated by the output current value is more linear, and the control accuracy of the permanent magnet motor is improved.

Description

Technical Field

[0001] This invention relates to the field of motor drive technology, and in particular to a method, apparatus, computer, and medium for improving the output linearity of a permanent magnet motor. Background Technology

[0002] Permanent magnet synchronous rotary motors, linear motors, and planar motors all utilize the electromagnetic force generated between permanent magnets and energized coils for driving, and can be collectively classified as permanent magnet motors. Permanent magnet motors use permanent magnets for excitation and have advantages such as simple structure, high power density, high positioning accuracy, fast response speed, and safety and reliability, making them widely used in various electromechanical systems.

[0003] For general motion systems, the torque and drive current of a single-phase permanent magnet rotary motor can be approximated as linear, meaning the motor torque increases or decreases linearly with the drive current. However, for precision and ultra-precision motion system applications, due to spatial variations in the motor armature coil and magnetic field, as well as manufacturing errors, the relationship between motor torque and drive current exhibits significant nonlinearity. This poses challenges to the design of system motion control algorithms and will significantly affect the system's motion accuracy.

[0004] The typical driving principle of a permanent magnet motor involves passing a three-phase current with a 120° phase difference into the coil, perpendicular to the phase of the electromagnetic field distribution. Ideally, the resultant force or torque of the electromagnetic interaction between the energized coil and the permanent magnet is proportional to the amplitude of the three-phase current. However, because the magnetic field strength of the permanent magnet does not exhibit an ideal sinusoidal variation in spatial distribution, the resultant electromagnetic force acting on the energized coil deviates from the ideal value. This causes the actual output motor thrust or torque to deviate from a linear relationship with the current amplitude and the target output force, resulting in reduced motor output linearity. This significantly increases the difficulty of motor control, making it difficult for the motor to meet targets such as high response speed and high positioning accuracy. For example, thrust fluctuations exist in linear motors. Current research typically attributes these thrust fluctuations to factors such as cogging effect, end effect, and ripple thrust. Thrust fluctuations reduce the thrust linearity of the linear motor, meaning the relationship between the motor current and the actual output thrust deviates from linearity, leading to strong nonlinearity in motor drive and posing significant challenges to precise motor control.

[0005] To improve the linearity of motor output, a common solution is to optimize the motor structure design to minimize the nonlinearity of output force, see patents CN113054762 and CN213547339. However, structural optimization not only increases manufacturing costs, but can only reduce, not completely eliminate, the nonlinearity of motor output force.

[0006] In addition, another type of method to improve the linearity of motor output involves accurately modeling the motor to calculate the distribution of the electromagnetic field within the motor in order to accurately calculate the actual output force or torque of the motor. See Shen Haitao, Wang Qi, Ji Xiaokai, Zhang Kai, Zhou Yuan. Thrust fluctuation compensation technology for linear motors. Electrical Machines and Control Applications, 2022, 49(09):44-49+56. and Liu Chengying, Wang Hao, Zhang Zhijing, Shen Xiangming. Research on electromagnetic thrust characteristics of permanent magnet linear synchronous motor based on nonlinear inductance analysis. Proceedings of the CSEE, 2011, 31(30):69-76. However, whether using analytical methods or finite element simulation methods to calculate the electromagnetic field distribution, the calculation is carried out using the established motor structure model. In reality, the actual values ​​of structural parameters of the motor during component processing and installation are inconsistent with the theoretical model values. For example, the spacing, size, shape and polarization intensity of permanent magnets in the model, and the relative position of the coil and permanent magnets deviate from the actual situation. This leads to deviations between the electromagnetic field calculation results and the corresponding actual values, and the linearity of the motor output is still limited.

[0007] In summary, improving the linearity of motor output is of great significance for improving the response speed, positioning accuracy, and other performance characteristics of permanent magnet motors. Existing methods for compensating for the nonlinearity of motor output force start by establishing an electromagnetic field model that approximates the actual motor structure as closely as possible. The coil current input is determined by model calculation. However, the calculation results will inevitably contain errors caused by inaccurate models. Therefore, the improvement in linearity is limited and still cannot meet the high requirements for motor output linearity in precision and ultra-precision motion applications. Summary of the Invention

[0008] Therefore, it is necessary to provide a method, apparatus, computer, and medium for improving the output linearity of a permanent magnet motor to address the aforementioned technical problems.

[0009] A method for improving the output linearity of a permanent magnet motor includes:

[0010] Obtain a preset current value, and apply current to the permanent magnet motor according to the preset current value;

[0011] The displacement information of the mover of the permanent magnet motor is obtained by measurement;

[0012] The preset current value and the displacement information are substituted into the preset motor dynamics model for solution to obtain the corrected electromagnetic force coefficient;

[0013] Obtain the target output power;

[0014] The corrected electromagnetic force coefficient and the target output power are substituted into the preset motor dynamics model to calculate the output current value.

[0015] In one embodiment, the step of obtaining a preset current value and applying current to the permanent magnet motor according to the preset current value includes:

[0016] Obtain the preset current value based on a preset pattern of change, and apply current to the permanent magnet motor according to the preset current value.

[0017] In one embodiment, the step of measuring the displacement information of the mover of the permanent magnet motor includes:

[0018] The displacement information is obtained by measuring the displacement of the mover of the permanent magnet motor as a function of the preset current value.

[0019] In one embodiment, in the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor is equal to the output power of the permanent magnet motor, wherein the electromagnetic results of each phase is the product of the electromagnetic force coefficient of the phase coil and the current of the phase coil.

[0020] In one embodiment, in the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor minus the frictional force of the mover of the permanent magnet motor equals the output power of the permanent magnet motor, wherein the electromagnetic results of each phase is the product of the electromagnetic force coefficient of the phase coil and the current of the phase coil.

[0021] In one embodiment, the step of substituting the corrected electromagnetic force coefficient and the target output power into the preset motor dynamics model to calculate the output current value includes:

[0022] The corrected electromagnetic force coefficient and the target output power are substituted into the nonlinear equation set, which is constructed by the preset motor dynamics model, the current relationship of the three-phase coil, and the total power calculation formula of the motor coil.

[0023] The output current value is calculated by solving the nonlinear equations.

[0024] A device for improving the output linearity of a permanent magnet motor, comprising:

[0025] A preset current value acquisition module is used to acquire a preset current value and apply current to the permanent magnet motor according to the preset current value.

[0026] The displacement information measurement module is used to measure and obtain the displacement information of the mover of the permanent magnet motor;

[0027] The electromagnetic force coefficient correction module is used to substitute the preset current value and the displacement information into the preset motor dynamics model to solve for the corrected electromagnetic force coefficient.

[0028] The target output power acquisition module is used to acquire the target output power.

[0029] The output current value calculation module is used to substitute the corrected electromagnetic force coefficient and the target output power into the preset motor dynamics model to calculate the output current value.

[0030] A computer device includes a memory and a processor, the memory storing a computer program, characterized in that the processor executes the computer program to implement the steps of any of the above embodiments of the method for improving the output linearity of a permanent magnet motor.

[0031] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in any embodiment of the method for improving the output linearity of a permanent magnet motor described above. A computer program, when executed by a processor, implements the steps in any embodiment of the method for improving the output linearity of a permanent magnet motor described above.

[0032] The aforementioned method, device, computer, and medium for improving the output linearity of a permanent magnet motor input the preset current value and the displacement information of the mover obtained in real time into a preset motor dynamics model to correct the electromagnetic force coefficient, thereby obtaining an accurate electromagnetic force coefficient. Based on the corrected electromagnetic force coefficient and the target output power, the output current value is calculated by inputting it into the motor dynamics model. Through the above process, the output power generated by the output current value can be made more linear, thereby effectively improving the control accuracy of the permanent magnet motor. Attached Figure Description

[0033] Figure 1 This is a flowchart illustrating a method for improving the output linearity of a permanent magnet motor in one embodiment;

[0034] Figure 2 This is a structural block diagram of a device for improving the output linearity of a permanent magnet motor in one embodiment;

[0035] Figure 3 This is an internal structural diagram of a computer device in one embodiment.

[0036] Figure 4 A schematic diagram illustrating the logical relationship between the drive current and electromagnetic force of a permanent magnet motor, provided as an embodiment.

[0037] Figure 5 A flowchart illustrating a method for improving the output linearity of a permanent magnet motor, provided in one embodiment;

[0038] Figure 6 This is a schematic diagram of a three-phase coil linear motor in one embodiment;

[0039] Figure 7 This is a schematic diagram of a three-phase coil structure permanent magnet synchronous rotating motor in one embodiment. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0041] Example 1

[0042] In this embodiment, as Figure 1 As shown, a method for improving the output linearity of a permanent magnet motor is provided, which includes:

[0043] Step 110: Obtain a preset current value and apply current to the permanent magnet motor according to the preset current value.

[0044] In this embodiment, the preset current value is the value of the driving current. In this embodiment, a circuit with a current value of the preset current value is supplied to the coil of the permanent magnet motor to drive the permanent magnet motor to work. When current is supplied to the coil of the permanent magnet motor, the generated magnetic field will drive the mover of the permanent magnet motor to move.

[0045] In one embodiment, a preset current value that changes according to a preset pattern is obtained, and current is supplied to the permanent magnet motor according to the preset current value. In this embodiment, the preset current value changes according to a preset pattern, so that the current input to the coil of the permanent magnet motor is variable. In this embodiment, the preset current value is different at different times t, and the preset current value can be expressed as I. (t) .

[0046] Step 120: Measure and obtain the displacement information of the mover of the permanent magnet motor.

[0047] In this embodiment, the displacement distance of the mover, generated by the current input to the coil of the permanent magnet motor, is measured, and this displacement distance is the displacement information. It is worth mentioning that the displacement information can be linear displacement or circular displacement. In one embodiment, the permanent magnet motor is a permanent magnet linear motor, and the displacement information is the displacement distance. In another embodiment, the permanent magnet motor is a permanent magnet rotary motor, and the displacement information is the rotation angle.

[0048] In one embodiment, the displacement information is obtained by measuring the change in displacement of the permanent magnet motor's mover as a preset current value changes. In this embodiment, since the current input to the permanent magnet motor's coil changes, the displacement of the permanent magnet motor's mover also changes. Therefore, by measuring the change in displacement of the permanent magnet motor as a function of the preset current value in real time, the time-varying displacement x is obtained. (t), where t is time and x is displacement.

[0049] Step 130: Substitute the preset current value and the displacement information into the preset motor dynamics model to solve for the corrected electromagnetic force coefficient.

[0050] It is worth mentioning that the electromagnetic force coefficient can also be the electromagnetic torque coefficient. In some embodiments, when the permanent magnet motor is a permanent magnet rotary motor, the electromagnetic force coefficient is the electromagnetic torque coefficient.

[0051] In one embodiment, in the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor is equal to the output power of the permanent magnet motor, wherein the electromagnetic results of each phase is the product of the electromagnetic force coefficient of the phase coil and the current of the phase coil.

[0052] In one embodiment, in the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor minus the frictional force of the permanent magnet motor's mover equals the output power of the permanent magnet motor, wherein the electromagnetic results of each phase is the product of the electromagnetic force coefficient of that phase coil and the current of that phase coil.

[0053] In this embodiment, a three-phase coil structure permanent magnet linear motor is used as an example, and a preset current is applied.

[0054]

[0055] Where A,ω are constants and t is time.

[0056] Record the current data {I1(t)} obtained by sampling at equal time intervals during the process of applying a preset current and the motor generating motion. n )},{I2(t n )},{I3(t n )}, n=1,2,...,N and displacement data {x(t n )}, n=1,2,...,N.

[0057] The pre-defined motor dynamics model is as follows:

[0058]

[0059] Where x is the displacement of the mover, t is time, K1(x), K2(x), and K3(x) are the electromagnetic force coefficients of the A, B, and C phase coils, respectively, I1, I2, and I3 are the current values ​​flowing through the A, B, and C phase coils, respectively. The product of the electromagnetic force coefficient of each phase coil and the current flowing through it is the resultant electromagnetic force on the coil, f(x,t) is the frictional force exerted by the motor guide rail on the mover, and m is the mass of the mover. Let x be the second derivative of x with respect to time t, i.e., the motioner acceleration, and m be the second derivative of x with respect to time t. The product of represents the power output of the motor.

[0060] The models for the electromagnetic force coefficients K1(x), K2(x), and K3(x) are as follows:

[0061]

[0062] Where {x(k)}, k = 1, 2, ... is a sequence with equal step size, and {L1(k)}, {L2(k)}, {L3(k)}, k = 1, 2, ... is a sequence of constants to be determined.

[0063] The model for frictional force f(x,t) is f(x,t)=0.

[0064] The sampled N sets of current data {I1(t) n )},{I2(t n )},{I3(t n )}, n=1,2,...,N and displacement data {x(t n Substituting n = 1, 2, ..., N into the pre-established motor dynamics model, we obtain a system of nonlinear equations containing N equations.

[0065]

[0066] Among them, the motioner acceleration sequence From the displacement data sequence {x(t n The second difference of )} is obtained, i.e.

[0067]

[0068] Among them, T s This represents the sampling time interval.

[0069] The solution to the above equation system is obtained by using a numerical solution algorithm for nonlinear equation systems. The solution results are the correction values ​​of the undetermined constants {L1(k)}, {L2(k)}, {L3(k)}, k = 1, 2, ... Substituting them back into the electromagnetic force coefficient model yields the corrected electromagnetic force coefficients K1(x), K2(x), and K3(x).

[0070] In this embodiment, the preset current value that changes according to a preset rule and the displacement information of the mover that changes accordingly are substituted into the preset motor dynamics model mentioned above to solve the problem, so as to obtain the electromagnetic force coefficient of each phase of the permanent magnet motor. Since the electromagnetic force coefficient is calculated based on the real-time changing coil current and the mover displacement, the electromagnetic force coefficient is corrected and more accurate.

[0071] Step 140: Obtain the target output power.

[0072] In this embodiment, the target output power is the power that needs to be output by the permanent magnet motor.

[0073] Step 150: Substitute the corrected electromagnetic force coefficient and the target output power into the preset motor dynamics model to calculate the output current value.

[0074] In this embodiment, the corrected electromagnetic force coefficient and the target output power are substituted into the preset motor dynamics model as known values ​​to calculate the output current value required for the target output power. In some embodiments, the target output power changes linearly along the time axis; therefore, the output point distance calculated based on this also changes linearly, thereby effectively improving the linearity of the power output of the permanent magnet motor.

[0075] Step 160: Apply current to the permanent magnet motor according to the output current value.

[0076] In this embodiment, based on the output current value calculated from the target output power, the current corresponding to the output current value is input to the coil of the permanent magnet motor, thereby driving the permanent magnet motor to work and enabling the permanent magnet motor to output the target output power.

[0077] In one embodiment, the step of substituting the corrected electromagnetic force coefficient and the target output power into the preset motor dynamics model to calculate the output current value includes: substituting the corrected electromagnetic force coefficient into the preset motor dynamics model to obtain a motor power correction model; and calculating the output current value based on the target output power and the motor power correction model.

[0078] In this embodiment, the corrected electromagnetic force coefficient is substituted into the preset motor dynamics model to obtain a motor dynamics model with the electromagnetic force coefficient determined. This motor dynamics model is the motor power correction model. The output current value can be calculated by substituting the target output power into the motor power correction model.

[0079] In one embodiment, the step of substituting the corrected electromagnetic force coefficient and the target output power into the preset motor dynamics model to calculate the output current value includes: substituting the corrected electromagnetic force coefficient and the target output power into a nonlinear equation set, wherein the nonlinear equation set is constructed by the preset motor dynamics model, the current relationship of the three-phase coil, and the total power calculation formula of the motor coil; solving the nonlinear equation set to calculate the output current value.

[0080] In this embodiment, the real-time displacement x(t) is substituted into the corrected electromagnetic force coefficient model K1(x), K2(x), K3(x) to calculate the real-time electromagnetic force coefficients K1[x(t)], K2[x(t)], K3[x(t)]. These coefficients, along with the target output power F(t) of the motor, are then substituted into the aforementioned motor dynamics model to obtain...

[0081] K1[x(t)]I1+K2[x(t)]I2+K3[x(t)]I3=F(t)

[0082] For a three-phase coil in a linear motor with a star connection, the sum of the currents will be zero. Therefore, the current relationship of the three-phase coil is:

[0083] I1+I2+I3=0

[0084] By constraining the total power of the motor coil current, the formula for calculating the total power of the motor coil is obtained as follows:

[0085]

[0086] Where P is a constant.

[0087] Based on the aforementioned preset motor dynamics model, the current relationship of the three-phase coils, and the formula for calculating the total power of the motor coils, a set of nonlinear equations is constructed. The corrected electromagnetic force coefficient and the target output power are substituted into the preset motor dynamics model of the nonlinear equations, and the output current value of each phase coil is obtained by solving the set of nonlinear equations.

[0088] It should be understood that, although Figure 1 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0089] Example 2

[0090] For example Figure 6 The permanent magnet motor with the functional structure shown is as follows: Figure 5 As shown, the present invention provides a method for improving the output linearity of a permanent magnet motor, comprising:

[0091] Step 1: Use an algorithm to automatically correct the electromagnetic force coefficient of the motor.

[0092] In this embodiment, for example, Figure 6 The three-phase coil structure linear motor shown is... Figure 6 In the middle, a preset current is applied to phase A coil 301, phase B coil 302, phase C coil 303, permanent magnet array A 311, and permanent magnet array B 312.

[0093]

[0094] Where A,ω are constants and t is time.

[0095] Record the current data {I1(t)} obtained by sampling at equal time intervals during the process of applying a preset current and the motor generating motion. n )},{I2(t n )},{I3(t n )}, n=1,2,...,N and displacement data {x(t n )}, n=1,2,...,N.

[0096] Figure 6 The dynamic model of the electric motor can be based on Figure 4 Based on the established logical relationships, the motor dynamics model is thus established as follows:

[0097]

[0098] Where x is the displacement of the mover, t is time, K1(x), K2(x), K3(x) and I1, I2, I3 are the electromagnetic force coefficients and currents flowing through the coils of phases A, B, and C, respectively. The product of the electromagnetic force coefficient and the current flowing through each phase coil is the resultant electromagnetic force on the coil, f(x,t) is the frictional force exerted by the motor guide rails on the mover, and m is the mass of the mover. Let x be the second derivative of x with respect to time t, which is the motioner acceleration.

[0099] The models for the electromagnetic force coefficients K1(x), K2(x), and K3(x) are as follows:

[0100]

[0101] Where {x(k)}, k = 1, 2, ... is a sequence with equal step size, and {L1(k)}, {L2(k)}, {L3(k)}, k = 1, 2, ... is a sequence of constants to be determined.

[0102] The model for frictional force f(x,t) is f(x,t)=0.

[0103] The sampled N sets of current data {I1(t) n)},{I2(t n )},{I3(t n )}, n=1,2,...,N and displacement data {x(t n Substituting the values ​​of n = 1, 2, ..., N into the established motor dynamics model yields a system of N nonlinear equations.

[0104]

[0105] Among them, the motioner acceleration sequence From the displacement data sequence {x(t n The second difference of )} is obtained, i.e.

[0106]

[0107] Among them, T s This represents the sampling time interval.

[0108] The solutions to the above equations are obtained using a numerical algorithm for solving nonlinear equations. The solutions are the correction values ​​for the undetermined constants {L1(k)}, {L2(k)}, {L3(k)}, k = 1, 2, ... Substituting these values ​​back into the electromagnetic force coefficient model yields the corrected electromagnetic force coefficients K1(x), K2(x), and K3(x).

[0109] Step 2: Calculate the coil input current in real time using the electromagnetic force coefficient correction result, and input the current result to the motor coil.

[0110] In one implementation,

[0111] Substituting the real-time displacement x(t) into the corrected electromagnetic force coefficient model K1(x), K2(x), K3(x), the real-time electromagnetic force coefficients K1[x(t)], K2[x(t)], and K3[x(t)] are calculated. These, along with the target output thrust F(t) of the motor, are then substituted into the aforementioned motor dynamics model to obtain...

[0112] K1[x(t)]I1+K2[x(t)]I2+K3[x(t)]I3=F(t)

[0113] For a three-phase coil in a linear motor with a star connection, the sum of the currents will be zero, i.e.

[0114] I1+I2+I3=0

[0115] Constrain the total power of the motor coil current, i.e.

[0116]

[0117] Where P is a constant.

[0118] By combining the above three equations, we obtain a set of nonlinear equations concerning the coil currents I1, I2, and I3. Solving this set of nonlinear equations yields the coil currents I1, I2, and I3.

[0119] By using hardware circuitry to pass currents of the calculated values ​​of I1, I2, and I3 into the coil, a high-linearity motor thrust output can be achieved.

[0120] Example 3

[0121] For example Figure 7 The permanent magnet motor with the functional structure shown is as follows: Figure 5 As shown, the present invention provides a method for improving the output linearity of a permanent magnet motor, comprising:

[0122] Step 1: Use an algorithm to automatically correct the electromagnetic torque coefficient of the motor.

[0123] In this embodiment, for example, Figure 7 The three-phase coil structure permanent magnet synchronous rotating motor shown is... Figure 7 In this three-phase coil structure permanent magnet synchronous rotating motor, there are phase A coil 401, phase B coil 402, phase C coil 403, phase A coil 404, phase B coil 405, phase C coil 406, and a moving permanent magnet 411 (the moving permanent magnet 411 is the mover). A preset current is applied.

[0124]

[0125] Where A,ω are constants and t is time.

[0126] Record the current data {I1(t)} obtained by sampling at equal time intervals during the process of applying a preset current and the motor generating motion. n )},{I2(t n )},{I3(t n )}, n=1,2,...,N and angular displacement data {θ(t n )}, n=1,2,...,N.

[0127] like Figure 7 The motor dynamics model shown can be based on Figure 4 Based on the established logical relationships, the motor dynamics model is thus established as follows:

[0128]

[0129] Where θ is the motor rotation angle, t is time, K1(θ), K2(θ), K3(θ) and I1, I2, I3 are the electromagnetic torque coefficients and currents of the A, B, and C phase coils, respectively. The product of the electromagnetic torque coefficient and the current of each phase coil is the resultant electromagnetic torque on the coil. R(θ,t) is the motor friction torque, and J is the moment of inertia of the mover. Let θ be the second derivative of θ with respect to time t, which is the rotational acceleration.

[0130] The electromagnetic torque coefficients K1(θ), K2(θ), and K3(θ) are modeled as follows:

[0131]

[0132] Where p ij i = 1, 2, 3, j = 1, 2, 3, 4 are undetermined constants.

[0133] The frictional torque R(θ,t) model is R(θ,t)=q, where q is an undetermined constant.

[0134] The sampled N sets of current data {I1(t) n )},{I2(t n )},{I3(t n )}, n=1,2,...,N and displacement data {θ(t) n Substituting the values ​​of n = 1, 2, ..., N into the established motor dynamics model yields a system of N nonlinear equations.

[0135]

[0136] Among them, the motioner acceleration sequence From the displacement data sequence {θ(t) n The second difference of )} is obtained, i.e.

[0137]

[0138] Among them, T s This represents the sampling time interval.

[0139] The solution to the above system of equations is obtained using a numerical algorithm for solving nonlinear equations, and the solution result is the undetermined constant p. ij The correction values ​​of i = 1, 2, 3, j = 1, 2, 3, 4 and q are obtained by substituting them back into the electromagnetic torque coefficient model to obtain the corrected electromagnetic torque coefficients K1(θ), K2(θ), K3(θ).

[0140] Step 2: Calculate the coil input current in real time using the electromagnetic torque coefficient correction result, and input the current result to the motor coil.

[0141] In one implementation, the real-time displacement θ(t) is substituted into the corrected electromagnetic torque coefficient model K1(θ), K2(θ), K3(θ) to calculate the real-time electromagnetic torque coefficient.

[0142] Substituting K1[θ(t)], K2[θ(t)], and K3[θ(t)] together with the target output thrust M(t) of the motor into the above motor dynamics model, we obtain...

[0143] K1[θ(t)]I1+K2[θ(t)]I2+K3[θ(t)]I3=M(t)

[0144] For a three-phase coil in a permanent magnet synchronous rotating motor with a star connection, the sum of the currents will be zero, i.e.

[0145] I1+I2+I3=0

[0146] Constrain the total power of the motor coil current, i.e.

[0147]

[0148] Where P is a constant.

[0149] By combining the above three equations, we obtain a set of nonlinear equations concerning the coil currents I1, I2, and I3. Solving this set of nonlinear equations yields the coil currents I1, I2, and I3.

[0150] By using hardware circuitry to pass currents of the calculated values ​​of I1, I2, and I3 into the coil, a motor torque output with high linearity can be achieved.

[0151] Example 4

[0152] In this embodiment, as Figure 2 As shown, a device for improving the output linearity of a permanent magnet motor is provided, comprising:

[0153] The preset current value acquisition module 210 is used to acquire a preset current value and apply current to the permanent magnet motor according to the preset current value.

[0154] The displacement information measurement module 220 is used to measure and obtain the displacement information of the mover of the permanent magnet motor;

[0155] The electromagnetic force coefficient correction module 230 is used to substitute the preset current value and the displacement information into the preset motor dynamics model to solve for the corrected electromagnetic force coefficient.

[0156] The target output power acquisition module 240 is used to acquire the target output power;

[0157] The output current value calculation module 250 is used to substitute the corrected electromagnetic force coefficient and the target output power into the preset motor dynamics model to calculate the output current value.

[0158] The current input module 260 is used to input current into the permanent magnet motor according to the output current value.

[0159] In one embodiment, the preset current value acquisition module is further configured to acquire the preset current value based on a preset pattern of change, and to supply current to the permanent magnet motor according to the preset current value.

[0160] In one embodiment, the displacement information measurement module is further used to measure the displacement of the permanent magnet motor's mover as the preset current value changes, thereby obtaining the displacement information.

[0161] In one embodiment, in the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor is equal to the output power of the permanent magnet motor, wherein the electromagnetic results of each phase is the product of the electromagnetic force coefficient of the phase coil and the current of the phase coil.

[0162] In one embodiment, in the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor minus the frictional force of the permanent magnet motor's mover equals the output power of the permanent magnet motor, wherein the electromagnetic results of each phase is the product of the electromagnetic force coefficient of that phase coil and the current of that phase coil.

[0163] In one embodiment, the output current value calculation module includes:

[0164] The nonlinear equation construction unit is used to substitute the corrected electromagnetic force coefficient and the target output power into the nonlinear equation set, wherein the nonlinear equation set is constructed by the preset motor dynamics model, the current relationship of the three-phase coil, and the total power calculation formula of the motor coil;

[0165] The nonlinear equation solving unit is used to solve the set of nonlinear equations to calculate the output current value.

[0166] Specific limitations regarding the device for improving the output linearity of a permanent magnet motor can be found in the limitations of the method for improving the output linearity of a permanent magnet motor described above, and will not be repeated here. Each unit in the aforementioned device for improving the output linearity of a permanent magnet motor can be implemented entirely or partially through software, hardware, or a combination thereof. These units can be embedded in hardware or independently of the processor in a computer device, or stored in software in the memory of a computer device, so that the processor can call and execute the operations corresponding to each unit.

[0167] Example 5

[0168] In this embodiment, a computer device is provided. Its internal structure diagram can be shown as follows: Figure 3 As shown, the computer device includes a processor, memory, network interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system and computer programs, and also stores the mapping relationship between the magnetic field strength of the stator and the displacement distance of the mover of the permanent magnet synchronous linear motor. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The network interface is used to communicate with other computer devices that have deployed application software. When the processor executes the computer program, it implements a method to improve the output linearity of the permanent magnet motor. The display screen can be a liquid crystal display (LCD) or an e-ink display. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad mounted on the computer device casing, or an external keyboard, touchpad, or mouse.

[0169] Those skilled in the art will understand that Figure 3 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0170] In one embodiment, a computer device is provided, including a memory and a processor, the memory storing a computer program, the processor executing the computer program to perform the following steps:

[0171] Obtain a preset current value, and apply current to the permanent magnet motor according to the preset current value;

[0172] The displacement information of the mover of the permanent magnet motor is obtained by measurement;

[0173] The preset current value and the displacement information are substituted into the preset motor dynamics model for solution to obtain the corrected electromagnetic force coefficient;

[0174] Obtain the target output power;

[0175] Substitute the corrected electromagnetic force coefficient and the target output power into the preset motor dynamics model to calculate the output current value;

[0176] Current is supplied to the permanent magnet motor according to the output current value.

[0177] In one embodiment, the step of obtaining a preset current value and applying current to the permanent magnet motor according to the preset current value includes:

[0178] Obtain the preset current value based on a preset pattern of change, and apply current to the permanent magnet motor according to the preset current value.

[0179] In one embodiment, the step of measuring the displacement information of the mover of the permanent magnet motor includes:

[0180] The displacement information is obtained by measuring the displacement of the mover of the permanent magnet motor as a function of the preset current value.

[0181] In one embodiment, in the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor is equal to the output power of the permanent magnet motor, wherein the electromagnetic results of each phase is the product of the electromagnetic force coefficient of the phase coil and the current of the phase coil.

[0182] In one embodiment, in the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor minus the frictional force of the permanent magnet motor's mover equals the output power of the permanent magnet motor, wherein the electromagnetic results of each phase is the product of the electromagnetic force coefficient of that phase coil and the current of that phase coil.

[0183] In one embodiment, the processor, when executing a computer program, also performs the following steps:

[0184] The corrected electromagnetic force coefficient and the target output power are substituted into the nonlinear equation set, which is constructed by the preset motor dynamics model, the current relationship of the three-phase coil, and the total power calculation formula of the motor coil.

[0185] The output current value is calculated by solving the nonlinear equations.

[0186] Example 6

[0187] In this embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, it performs the following steps:

[0188] Obtain a preset current value, and apply current to the permanent magnet motor according to the preset current value;

[0189] The displacement information of the mover of the permanent magnet motor is obtained by measurement;

[0190] The preset current value and the displacement information are substituted into the preset motor dynamics model for solution to obtain the corrected electromagnetic force coefficient;

[0191] Obtain the target output power;

[0192] Substitute the corrected electromagnetic force coefficient and the target output power into the preset motor dynamics model to calculate the output current value;

[0193] Current is supplied to the permanent magnet motor according to the output current value.

[0194] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0195] Obtain the preset current value based on a preset pattern of change, and apply current to the permanent magnet motor according to the preset current value.

[0196] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0197] The displacement information is obtained by measuring the displacement of the mover of the permanent magnet motor as a function of the preset current value.

[0198] In one embodiment, in the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor is equal to the output power of the permanent magnet motor, wherein the electromagnetic results of each phase is the product of the electromagnetic force coefficient of the phase coil and the current of the phase coil.

[0199] In one embodiment, in the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor minus the frictional force of the permanent magnet motor's mover equals the output power of the permanent magnet motor, wherein the electromagnetic results of each phase is the product of the electromagnetic force coefficient of that phase coil and the current of that phase coil.

[0200] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0201] The corrected electromagnetic force coefficient and the target output power are substituted into the nonlinear equation set, which is constructed by the preset motor dynamics model, the current relationship of the three-phase coil, and the total power calculation formula of the motor coil.

[0202] The output current value is calculated by solving the nonlinear equations.

[0203] Example 7

[0204] In this embodiment, a computer program is provided, which, when executed by a processor, performs the following steps:

[0205] Obtain a preset current value, and apply current to the permanent magnet motor according to the preset current value;

[0206] The displacement information of the mover of the permanent magnet motor is obtained by measurement;

[0207] The preset current value and the displacement information are substituted into the preset motor dynamics model for solution to obtain the corrected electromagnetic force coefficient;

[0208] Obtain the target output power;

[0209] Substitute the corrected electromagnetic force coefficient and the target output power into the preset motor dynamics model to calculate the output current value;

[0210] Current is supplied to the permanent magnet motor according to the output current value.

[0211] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0212] Obtain the preset current value based on a preset pattern of change, and apply current to the permanent magnet motor according to the preset current value.

[0213] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0214] The displacement information is obtained by measuring the displacement of the mover of the permanent magnet motor as a function of the preset current value.

[0215] In one embodiment, in the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor is equal to the output power of the permanent magnet motor, wherein the electromagnetic results of each phase is the product of the electromagnetic force coefficient of the phase coil and the current of the phase coil.

[0216] In one embodiment, in the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor minus the frictional force of the permanent magnet motor's mover equals the output power of the permanent magnet motor, wherein the electromagnetic results of each phase is the product of the electromagnetic force coefficient of that phase coil and the current of that phase coil.

[0217] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0218] The corrected electromagnetic force coefficient and the target output power are substituted into the nonlinear equation set, which is constructed by the preset motor dynamics model, the current relationship of the three-phase coil, and the total power calculation formula of the motor coil.

[0219] The output current value is calculated by solving the nonlinear equations.

[0220] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0221] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0222] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for improving the output linearity of a permanent magnet motor, characterized in that, include: Obtain a preset current value, and apply current to the permanent magnet motor according to the preset current value; The displacement information of the mover of the permanent magnet motor is obtained by measurement; The preset current value and the displacement information are substituted into the preset motor dynamics model to solve for the corrected electromagnetic force coefficient of each phase. Obtain the target output power; Substitute the corrected electromagnetic force coefficient and the target output power into the preset motor dynamics model to calculate the output current value; The step of obtaining a preset current value and applying current to the permanent magnet motor according to the preset current value includes: Obtain the preset current value that changes according to a preset pattern, and apply current to the permanent magnet motor according to the preset current value; The step of measuring and obtaining the displacement information of the mover of the permanent magnet motor includes: The displacement information is obtained by measuring the displacement of the mover of the permanent magnet motor as a function of the preset current value. The step of substituting the corrected electromagnetic force coefficient and the target output power into the preset motor dynamics model to calculate the output current value includes: The corrected electromagnetic force coefficient and the target output power are substituted into the nonlinear equation set, which is constructed by the preset motor dynamics model, the current relationship of the three-phase coil, and the total power calculation formula of the motor coil. The output current value is calculated by solving the nonlinear equations.

2. The method according to claim 1, characterized in that, In the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor is equal to the output power of the permanent magnet motor, wherein the electromagnetic results of each phase is the product of the electromagnetic force coefficient of the phase coil and the current of the phase coil.

3. The method according to claim 1, characterized in that, In the preset motor dynamics model, the sum of the electromagnetic results of the three-phase coils of the permanent magnet motor minus the frictional force of the permanent magnet motor's mover equals the output power of the permanent magnet motor. Here, the electromagnetic results of each phase is the product of the electromagnetic force coefficient of that phase coil and the current of that phase coil.

4. An apparatus for improving the output linearity of a permanent magnet motor, used to implement the method for improving the output linearity of a permanent magnet motor as described in any one of claims 1-3, characterized in that, include: A preset current value acquisition module is used to acquire a preset current value and apply current to the permanent magnet motor according to the preset current value; The displacement information measurement module is used to measure and obtain the displacement information of the mover of the permanent magnet motor; The electromagnetic force coefficient correction module is used to substitute the preset current value and the displacement information into the preset motor dynamics model to solve for the corrected electromagnetic force coefficient. The target output power acquisition module is used to acquire the target output power. The output current value calculation module is used to substitute the corrected electromagnetic force coefficient and the target output power into the preset motor dynamics model to calculate the output current value.

5. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 3.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 3.

7. A computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 3.

Images