Research on Sliding Mode Control of IC Packaging Equipment Precision Motion Platform with Disturbance Compensation

摘要

the permanent magnet linear synchronous motor (PMLSM) is widely used in the drive motor of high-precision motion platform in IC packaging equipment. Since the servo system of the PMLSM motion platform is susceptible to uncertain factors such as nonlinear effect and external disturbance, traditional PID control methods are difficult to achieve the desired control effects. Aiming to decrease the influence of disturbance and nonlinear friction in PMLM model, a strategy of sliding mode control with RBF neural network and disturbance compensation was proposed. The RBF neural network was used to approximate the system disturbance, which improves the performance of the sliding mode controller. Lyapunov stability analysis to prove the stability of the sliding mode control strategy was provided. The nonlinear friction as disturbance compensation acts into the PMLSM Controller, which reduces the crawling and oscillating phenomenon caused by the friction force and improves the positioning accuracy of the motion platform. A feed-forward controller is added in the control system to improve the response time. The simulation results of MATLAB simulation platform show that control strategy improves the robustness, the response speed and positioning accuracy of the system comparing to the traditional PID control strategy.