Thrust ripple compensation method for permanent magnet synchronous linear motor

Abstract

The invention relates to a permanent magnet synchronous linear motor thrust ripple compensation method. An addition and subtraction arithmetic unit, a feedback controller, a thrust ripple compensation signal, an addition arithmetic unit and a controlled object are included. The input end of the addition and subtraction arithmetic unit is connected with the output ends of the reference trajectory and the controlled object so as to determine a trajectory tracking error and output the trajectory tracking error to the feedback controller; the feedback controller generates a feedback control signal based on the trajectory tracking error; the output end of the feedback controller and the output end of the thrust fluctuation compensation signal are connected with the input end of the addition arithmetic unit; the output end of the addition arithmetic unit is connected with the input end of the controlled object; carrying out iterative optimization on parameters of the thrust fluctuation compensation signal according to a uniform speed section trajectory tracking error, and stopping iteration when an iteration termination condition is met; according to the thrust fluctuation compensation method, the influence of the thrust fluctuation of the permanent magnet synchronous linear motor on the motion precision can be effectively suppressed, and the obtained optimal thrust fluctuation compensation signal parameter is still effective when a trajectory tracking task is changed.

Description

Technical Field

[0001] This invention relates to the semiconductor field of precision motion control, and in particular to a method for compensating thrust fluctuations in a permanent magnet synchronous linear motor. Background Technology

[0002] Permanent magnet synchronous linear motors are widely used in high-precision linear motion control fields such as precision machining, semiconductor manufacturing, and rail transportation due to their high power density, fast dynamic response, and direct drive characteristics. However, thrust ripple has always been a key factor restricting its performance improvement. The generation of thrust ripple is related to cogging effect, motor phase-finding accuracy, magnet position, and coil shape. Thrust ripple can significantly reduce motion smoothness, leading to decreased positioning accuracy, increased vibration and noise, and even affecting the lifespan of the control system.

[0003] Nowadays, with the increasing demand for high-speed and ultra-precision motion control, the impact of thrust fluctuations on the accuracy of precision motion control can no longer be ignored. Traditional control methods that do not consider the impact of thrust fluctuation disturbances can no longer meet current production and control needs. Summary of the Invention

[0004] Therefore, it is necessary to provide a thrust fluctuation compensation method for permanent magnet synchronous linear motors to address the problem of thrust fluctuation affecting motion control accuracy.

[0005] A method for compensating thrust fluctuations in a permanent magnet synchronous linear motor, the method comprising: a thrust fluctuation compensation signal. U f Parameterization method, thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f The parameter iterative optimization method and the iteration termination condition.

[0006] The thrust fluctuation compensation signal U f The parameterization method uses the periodic relationship between the thrust fluctuation equivalent voltage and the motor position to calculate the thrust fluctuation compensation signal. U f Expressed mathematically in terms of a finite number of parameters and basis functions, the expression is:

[0007] in, For the number of harmonics, and These represent the amplitudes of the corresponding sine and cosine harmonics, respectively. k The order of the harmonics. rThe reference trajectory used for the trajectory tracking task. For the pole pitch and thrust fluctuation compensation signal of a permanent magnet synchronous linear motor. U f parameters basis functions ; The thrust fluctuation compensation signal U f The parameter iterative optimization method is based on the tracking error of the uniform velocity segment. e c The thrust fluctuation compensation signal is updated using an iterative optimization method. U f parameter r Continue until the iteration termination condition is met; The iteration termination condition is to determine the thrust fluctuation compensation signal. U f parameter r The criterion for stopping the iteration is as follows: if the iteration termination condition is met, then the iteration is stopped, and the thrust fluctuation compensation signal can be considered as such. U f Parameter optimization objective function J The thrust fluctuation compensation signal is obtained when the minimum value is reached. U f If the parameters are optimal, continue iterating until the iteration termination condition is met.

[0008] The thrust fluctuation compensation signal U f Parameter optimization objective function J It is the tracking error of the uniform velocity segment. e c The sum of squares, by minimizing the thrust fluctuation compensation signal. U f Parameter optimization objective function J Determine the thrust fluctuation compensation signal U f The optimal parameters are expressed as:

[0009] in N The sampling length; The thrust fluctuation compensation signal U f The parameter iterative optimization method is as follows:

[0010] in, j This represents the number of iterations. For the learning law, the value takes a range from 0 to 1; ( () is the thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters r The first derivative in The value at; ( () is the thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters r The Hessian matrix in The value at; Tracking error of uniform velocity segment Thrust fluctuation compensation signal U f parameters r Partial derivative The specific expression is:

[0011] in, It is obtained by approximating the value by introducing parameter perturbation. To compensate for thrust fluctuations The trajectory tracking error during the uniform velocity segment will be recorded in the next trajectory tracking task. To compensate for thrust fluctuations The trajectory tracking error during the uniform velocity segment will be recorded in the next trajectory tracking task. This is the perturbation value, which is determined based on actual control requirements.

[0012] ( The specific expression for ) is:

[0013] in, For the tracking error of the uniform velocity segment Thrust fluctuation compensation signal U f parameters r The partial derivative, To compensate for thrust fluctuations Next, proceed to the next step j The tracking error of the uniform velocity segment recorded in the trajectory tracking task.

[0014] ( The specific expression for ) is:

[0015] in, For the tracking error of the uniform velocity segment Thrust fluctuation compensation signal U f parameters r The partial derivative, For the tracking error of the uniform velocity segment Thrust fluctuation compensation signal U f parameters r The transpose of the partial derivative; The specific steps of the thrust fluctuation compensation method for the permanent magnet synchronous linear motor are as follows: Step 1: Perform trajectory tracking task and analyze the trajectory tracking error of the permanent magnet synchronous linear motor in the constant speed segment. e c A fast Fourier transform is performed to obtain the periodic relationship between the thrust fluctuation equivalent voltage and the motor position; Step two: Based on the periodic relationship between the equivalent voltage of thrust fluctuation and the motor position, adjust the thrust fluctuation compensation signal. U f Perform parameter settings; Step 3, Initialization, let the number of iterations be... j =0, set thrust fluctuation compensation signal U f initial parameters ; Step 4: Estimate the tracking error of the permanent magnet synchronous linear motor in the uniform speed segment. Thrust fluctuation compensation signal U f parameters r partial derivatives ; Step 5, in the thrust fluctuation compensation signal Next, proceed to the next step j This trajectory tracking task records the trajectory tracking error during the constant velocity segment. ; Step 6: Estimate the thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters r The first derivative in The value at the location ( ); Step 7: Estimate the thrust fluctuation compensation signal Uf Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters r The Hessian matrix in Value at location ( ); Step 8: Based on the thrust fluctuation compensation signal U f The parameter iterative optimization method updates the thrust fluctuation compensation signal. U f parameters r ,get ; Step nine, in the thrust fluctuation compensation signal Next, perform the (j+1)th trajectory tracking task and record the trajectory tracking error during the uniform velocity segment. ; Step 10, determine the first j If the result of the +1 trajectory tracking task meets the iteration termination condition, the iteration stops, and the thrust fluctuation compensation signal can be considered as such. U f Parameter optimization objective function J The thrust fluctuation compensation signal is obtained when the minimum value is reached. U f parameters Let be the optimal parameter; otherwise, let j = j +1, skip to step five; The thrust fluctuation compensation signal U f initial parameters r It can be set to zero.

[0016] The iteration termination condition can be:

[0017] in, It is determined based on the actual control requirements of the servo control system.

[0018] The iteration termination condition can also be:

[0019] in, It is determined based on the actual control requirements of the servo control system.

[0020] The iteration termination condition can also be:

[0021] in, It is determined based on the actual control requirements of the servo control system.

[0022] The thrust fluctuation compensation method for permanent magnet synchronous linear motors proposed in this invention can effectively solve the problem of low motion accuracy caused by thrust fluctuations when controlling permanent magnet synchronous linear motors. The method provided by this invention can effectively suppress the impact of thrust fluctuations on control accuracy during the operation of permanent magnet synchronous linear motors, significantly improve the control accuracy of permanent magnet synchronous linear motors, and the obtained optimal thrust fluctuation compensation signal parameters remain effective when changing trajectory tracking tasks. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a servo control system for thrust fluctuation compensation of a permanent magnet synchronous linear motor in one embodiment of the present invention; Figure 2 This is a thrust fluctuation compensation signal in one embodiment of the present invention. U f A flowchart illustrating the parameter tuning method; Figure 3 This is a schematic diagram of a fourth-order reference trajectory used in a trajectory tracking task in one embodiment of the present invention. Two trajectories with different velocities are used in this embodiment; trajectory 1 is used for thrust fluctuation compensation signal. U f After optimizing the parameters and obtaining the optimal parameters, the universality of the method of the present invention is verified using trajectory 2. Figure 4 In one embodiment of the present invention, the thrust fluctuation compensation signal is used under trajectory 1. U f Parameter optimization objective function J A schematic diagram illustrating the convergence process; Figure 5 In one embodiment of the present invention, a comparison is made of the tracking error of the uniform speed segment of trajectory 1 without thrust fluctuation compensation and with thrust fluctuation compensation using the method of the present invention under the tracking task of trajectory 1. Figure 6 In one embodiment of the present invention, thrust fluctuation compensation signal is obtained through trajectory 1. U f After optimizing the parameters, the tracking task of trajectory 2 is executed, and the tracking error of the uniform velocity segment of the trajectory is compared between the trajectory without thrust fluctuation compensation and the trajectory with thrust fluctuation compensation using the method of this invention. Detailed Implementation To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0024] The structure of the permanent magnet synchronous linear motor thrust fluctuation compensation servo control system in this implementation example is as follows: Figure 1 As shown, it includes: an addition / subtraction unit and a feedback controller. C Thrust fluctuation compensation signal U f Adder, Controlled object P ; The input of the adder / subtractor is connected to the reference trajectory. r and the controlled object P The output of the adder / subtractor is connected to the feedback controller. C The input terminal of the feedback controller C Output terminal and thrust fluctuation compensation signal U f The output terminal of the adder is connected to the input terminal of the adder, and the output terminal of the adder is connected to the controlled object. P The input terminal; Addition and subtraction operators obtain reference trajectories r and the position feedback signal output by the controlled object y According to the reference trajectory r and position signal y The difference determines the trajectory tracking error. e Track tracking error e Input feedback controller C ; Feedback controller C Based on trajectory tracking error e Generate feedback control signal u c The thrust fluctuation compensation signal U f The thrust fluctuation compensation signal is parameterized based on the periodic relationship between the thrust fluctuation equivalent voltage and the motor position. U f parameters r Based on the tracking error of the uniform velocity segment e c Iterative optimization, tracking error of uniform velocity segment trajectory e c For trajectory tracking error e The tracking error corresponding to a constant trajectory velocity is calculated, and the iteration is stopped when the iteration termination condition is met, resulting in the thrust fluctuation compensation signal. U f parameters r The optimal parameters; Adder gets feedback controller C Output feedback control signal u c Thrust fluctuation compensation signalU f Feedback control signal u c and thrust fluctuation compensation signal U f The sum is used to obtain the overall control signal. u , will the main control signal u Output to the controlled object P ; Controlled object P Received the total control signal output from the adder u Then, output position feedback signal y , will give position feedback signal y Feedback is sent to the addition and subtraction unit.

[0025] The controlled object in this implementation example P This is a motion table driven by a permanent magnet synchronous linear motor. In this embodiment, the tracking error of the uniform speed segment trajectory of the permanent magnet synchronous linear motor is analyzed. e c A fast Fourier transform is performed to obtain the periodic relationship between the equivalent voltage of thrust fluctuation and the motor position, thereby providing a thrust fluctuation compensation signal. U f The parameterization setting is expressed as follows:

[0026] Where r is the reference trajectory used for the trajectory tracking task, and the fourth-order reference trajectory used in this example is as follows: Figure 3 As shown, The pole pitch of the motor is 57mm in this example, and the thrust fluctuation compensation signal is... U f parameters basis functions .

[0027] In this implementation example, the thrust fluctuation compensation signal U f Parameter optimization objective function J It is the tracking error of the uniform velocity segment. e c The sum of squares is expressed as:

[0028] in N The sampling length is 0.0001 seconds in this embodiment.

[0029] In this implementation example, the tracking error of the uniform velocity segment trajectory... Thrust fluctuation compensation signal U f parameters rpartial derivatives The estimation method is as follows:

[0030] in, It is obtained by approximating the value by introducing parameter perturbation. This is the perturbation value, which is 0.01 in this implementation example. Initial thrust fluctuation compensation signal U f In this implementation example, the corresponding parameter is set to 0. In this implementation example, the thrust fluctuation compensation signal is used. The trajectory tracking error during the uniform velocity segment will be recorded in the next trajectory tracking task. To compensate for thrust fluctuations The trajectory tracking error of the uniform speed segment will be recorded in the next trajectory tracking task.

[0031] In this implementation example, the thrust fluctuation compensation signal U f The parameter iterative optimization method is as follows:

[0032] in, j This represents the number of iterations. For the learning law, it is set to 1 in this implementation example; ( () is the thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters r The first derivative in The value at; ( () is the thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters r The Hessian matrix in The value at that location.

[0033] In this implementation example, the thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters The first derivative in The value at the location ( The estimation method for ) is as follows:

[0034] in, For the tracking error of the uniform velocity segment Thrust fluctuation compensation signal U f parameters r The partial derivative, To compensate for thrust fluctuations Next, proceed to the next step j The tracking error of the uniform velocity segment recorded in the trajectory tracking task.

[0035] In this embodiment, the thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters The Hessian matrix in Value at location ( The estimation method for ) is as follows:

[0036] in, For the tracking error of the uniform velocity segment Thrust fluctuation compensation signal U f parameters The partial derivative, For the tracking error of the uniform velocity segment Thrust fluctuation compensation signal U f parameters The transpose of the partial derivative.

[0037] In this implementation example, the iteration termination condition is:

[0038] in, In this implementation example, take .

[0039] like Figure 2 As shown, the specific steps of the thrust fluctuation compensation method for permanent magnet synchronous linear motors are as follows: Step 1: Perform trajectory tracking task and analyze the trajectory tracking error of the permanent magnet synchronous linear motor in the constant speed segment. A fast Fourier transform is performed to obtain the periodic relationship between the thrust fluctuation equivalent voltage and the motor position; Step two: Based on the periodic relationship between the equivalent voltage of thrust fluctuation and the motor position, adjust the thrust fluctuation compensation signal. U f Perform parameter settings; Step 3, Initialization, let the number of iterations be... j =0, set thrust fluctuation compensation signal U f initial parameters r 0 ; Step 4: Estimate the tracking error of the permanent magnet synchronous linear motor in the uniform speed segment. Thrust fluctuation compensation signal U f parameters r partial derivatives ; Step 5, in the thrust fluctuation compensation signal Next, proceed to the next step j This trajectory tracking task records the trajectory tracking error during the constant velocity segment. ; Step 6: Estimate the thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters r The first derivative in The value at the location ( ); Step 7: Estimate the thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters r The Hessian matrix in Value at location ( ); Step 8: Based on the thrust fluctuation compensation signal U f The parameter iterative optimization method updates the thrust fluctuation compensation signal. U f parameters r ,get ; Step nine, in the thrust fluctuation compensation signal Next, perform the (j+1)th trajectory tracking task and record the trajectory tracking error during the uniform velocity segment. ; Step 10, determine the first jIf the result of the +1 trajectory tracking task meets the iteration termination condition, the iteration stops, and the thrust fluctuation compensation signal can be considered as such. U f Parameter optimization objective function J The thrust fluctuation compensation signal is obtained when the minimum value is reached. U f parameters Let be the optimal parameter; otherwise, let j = j +1, skip to step five; In this implementation example, under the tracking task of trajectory 1, as the thrust fluctuation compensation signal... U f Parameter tuning, thrust fluctuation compensation signal U f Parameter optimization objective function J The convergence situation is as follows Figure 4 As shown, thrust fluctuation compensation signal U f Parameter optimization objective function J It gradually converges, and the iteration termination condition is met in the second iteration, at which point the iteration can be stopped.

[0040] The application results of the method of the present invention in this embodiment are as follows: Figure 5 As shown, compared with the trajectory tracking error that does not consider the impact of thrust fluctuation, the method of the present invention effectively suppresses the impact of thrust fluctuation when performing the tracking task of trajectory 1, and has high trajectory tracking accuracy, which can effectively realize high-performance motion control of servo system.

[0041] The application results of the method of the present invention in this embodiment are as follows: Figure 6 As shown, thrust fluctuation compensation signals are obtained under the tracking task of trajectory 1. U f After determining the optimal parameters, the method of the present invention performs a trajectory tracking task for trajectory 2, which has a different velocity than trajectory 1. The method of the present invention can still effectively suppress the impact of thrust fluctuation.

[0042] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that various modifications and improvements can be made without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of protection of the present invention is defined by the appended claims rather than the foregoing description. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for compensating thrust fluctuations in a permanent magnet synchronous linear motor, characterized in that, Its servo control system includes the following elements: Addition and subtraction unit, feedback controller C Thrust fluctuation compensation signal U f Adder, Controlled object P Thrust fluctuation compensation signal U f Parameterization method, thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f The parameter iterative optimization method and the iterative termination condition; The input terminal of the adder / subtractor is connected to the reference trajectory. r and the controlled object P The output of the adder / subtractor is connected to the feedback controller. C The input terminal of the feedback controller C Output terminal and thrust fluctuation compensation signal U f The output terminal of the adder is connected to the input terminal of the adder, and the output terminal of the adder is connected to the controlled object. P The input terminal; The addition and subtraction operator obtains the reference trajectory. r and the position signal output by the controlled object y According to the reference trajectory r and position feedback signal y The difference determines the trajectory tracking error. e Track tracking error e Input feedback controller C ; The feedback controller C Based on trajectory tracking error e Generate feedback control signal u c The thrust fluctuation compensation signal U f parameters ρ Based on the tracking error of the uniform velocity segment e c Iterative optimization is performed, and iteration stops when the termination condition is met, where the tracking error of the uniform velocity segment is... e c For trajectory tracking error e The tracking error corresponding to a constant trajectory velocity, and the resulting thrust fluctuation compensation signal. U f parameters ρ The optimal parameters; The adder receives feedback from the controller. C Output feedback control signal u c and thrust fluctuation compensation signal U f Feedback control signal u c and thrust fluctuation compensation signal U f The sum is used to obtain the overall control signal. u , will the main control signal u Output to the controlled object P。 2. The method for compensating thrust fluctuations in a permanent magnet synchronous linear motor according to claim 1, characterized in that, The thrust fluctuation compensation signal U f The expression is: in, For the number of harmonics, and These represent the amplitudes of the corresponding sine and cosine harmonics, respectively. k The order of the harmonics. r The reference trajectory used for the trajectory tracking task. For the pole pitch and thrust fluctuation compensation signal of a permanent magnet synchronous linear motor. U f parameters basis functions .

3. The method for compensating thrust fluctuations in a permanent magnet synchronous linear motor according to claim 1, characterized in that, Thrust fluctuation compensation signal U f Parameter optimization objective function J It is the tracking error of the uniform velocity segment. e c ( ρ , t The sum of squares of ) is expressed as: in N This is the sampling length.

4. The thrust fluctuation compensation method for a permanent magnet synchronous linear motor according to claim 1, characterized in that, The thrust fluctuation compensation signal U f parameters ρ Iterative update law: in, j This represents the number of iterations. For the learning law, the value takes a range from 0 to 1; ( () is the thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters ρ The first derivative in The value at; ( () is the thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters ρ The Hessian matrix in The value at that location.

5. The method for compensating thrust fluctuations in a permanent magnet synchronous linear motor according to claim 1, characterized in that, Tracking error of uniform velocity segment e c Thrust fluctuation compensation signal U f parameters ρ The method for estimating the partial derivatives is as follows: in, It is obtained by approximating the value by introducing parameter perturbation. To compensate for thrust fluctuations The trajectory tracking error during the uniform velocity segment will be recorded in the next trajectory tracking task. To compensate for thrust fluctuations The trajectory tracking error during the uniform velocity segment will be recorded in the next trajectory tracking task. This is the perturbation value, which is determined based on actual control requirements.

6. The method for compensating thrust fluctuations in a permanent magnet synchronous linear motor according to claim 1, characterized in that, The thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters ρ The first derivative in The value at the location ( The estimation method for ) is as follows: in, For the tracking error of the uniform velocity segment Thrust fluctuation compensation signal U f parameters ρ The partial derivative, To compensate for thrust fluctuations Next, proceed to the next step j The tracking error of the uniform velocity segment recorded in the trajectory tracking task.

7. The thrust fluctuation compensation method for a permanent magnet synchronous linear motor according to claim 1, characterized in that, Thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters ρ The Hessian matrix in Value at location ( The estimation method for ) is as follows: in, ( ρ , t The tracking error of the uniform velocity segment is... e c Thrust fluctuation compensation signal U f parameters ρ The partial derivative, For the tracking error of the uniform velocity segment Thrust fluctuation compensation signal U f parameters ρ The transpose of the partial derivative.

8. The thrust fluctuation compensation method for a permanent magnet synchronous linear motor according to claim 1, characterized in that, The specific steps are as follows: Step 1: Perform trajectory tracking task and analyze the trajectory tracking error of the permanent magnet synchronous linear motor in the constant speed segment. e c A fast Fourier transform is performed to obtain the periodic relationship between the thrust fluctuation equivalent voltage and the motor position; Step two: Based on the periodic relationship between the equivalent voltage of thrust fluctuation and the motor position, adjust the thrust fluctuation compensation signal. U f Perform parameter settings; Step 3, Initialization, let the number of iterations be... j =0, set the thrust fluctuation compensation signal. U f initial parameters ρ ; Step 4: Estimate the tracking error of the permanent magnet synchronous linear motor in the uniform speed segment. Thrust fluctuation compensation signal U f parameters ρ partial derivatives ; Step 5, in the thrust fluctuation compensation signal U f= U f Next, proceed to the next step j This trajectory tracking task records the trajectory tracking error during the constant velocity segment. ; Step 6: Estimate the thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters ρ The first derivative in The value at the location ( ); Step 7: Estimate the thrust fluctuation compensation signal U f Parameter optimization objective function J Thrust fluctuation compensation signal U f parameters ρ The Hessian matrix in ρ j Value at location ( ); Step 8: Based on the thrust fluctuation compensation signal U f The parameter iterative optimization method updates the thrust fluctuation compensation signal. U f parameters ρ ,get ; Step nine, in the thrust fluctuation compensation signal Next, perform the (j+1)th trajectory tracking task and record the trajectory tracking error during the uniform velocity segment. ; Step 10, determine the first j If the result of the +1 trajectory tracking task meets the iteration termination condition, the iteration stops, and the thrust fluctuation compensation signal can be considered as such. U f Parameter optimization objective function J The thrust fluctuation compensation signal is obtained when the minimum value is reached. U f parameters Let be the optimal parameter; otherwise, let j = j +1, skip to step five.

9. The method for compensating thrust fluctuations in a permanent magnet synchronous linear motor according to claim 1, characterized in that, The iteration termination condition is: in, The specific requirements are determined based on the actual control needs of the servo control system. The iteration termination condition can also be: in, The specific requirements are determined based on the actual control needs of the servo control system. The iteration termination condition can also be: in, It is determined based on the actual control requirements of the servo control system.

Images