Control Parameter Optimization And Load Disturbance Rejection Control Of AC Servo System

The performance of the servo system is directly affected by the selection of control parameters;therefore,the improved ITAE(Integrated Time Absolute Error)is used as the step response evaluation index and the simplex substitution method is used to optimize the control parameters in order to achieve the best response performance of servo system.The servo system will be influenced by a variety of load disturbance in the running process;in order to reduce the disturbance effect on the system speed,an ESO(Expand State Observer)is used to estimate the system load torque,based on which a feedforward compensation for disturbances is employed in the current loop.This paper aiming at the tuning and optimization of the servo system's control parameters and active disturbance rejection control technique,mainly completed the following work: 1.Taking the permanent magnet synchronous motor servo system as an example,the control structure diagram of the current and speed loop were established.Then the control parameters of the current and speed loop were tuned with the classical control engineering theory.2.In order to get the tuning control parameters value,the identification theories of the electrical parameters and inertia were studied.In order to improve the disturbance rejection ability,a feedforward compensation for disturbances was employed in the current loop.3.Because of the error factors such as parameter identification,discretization of the actual system,the theoretical tuning of the control parameters could hardly meet the optimum operation state,therefore,the improved ITAE was used to evaluate the step response of the system and then the optimal control parameters were obtained by using the simplex method in the neighborhood of the control parameters.4.Based on Dspace(digital Signal Processing and Control Engineering),a semi physical simulation platform was built to verify the tuning and optimization of the control parameters.MATLAB/Simulink was used to simulate the disturbance rejection control.The experimental and simulation results showed that the proposed parameter optimization method and the disturbance rejection control method had good adaptability.