交流位置伺服系统自适应模糊PID控制器设计

摘要

In order to realize high precision position tracking in electromechanical servo system, in al usion to the effect of uncertain-ty, such as variation of inertia and moment, a novel fuzzy PID control er which is adapted for the sliding surface is proposed. The gradient method is used to make the real time modification of PID control er parameters and the fuzzy logic system is made close to the uncertainties, which can make the control er adjust the real time speed seffing value according to the servo system. Thus the in-fluence of perturbation of system parameters and external disturbance on the position servo system can be minimized. Final y, the a-daptive law of the uncertain parameter is derived by Lyapunov method. Simulation shows the proposed control er is of better robust-ness to parameters’ variation and external load disturbance, as wel as high-precision tracking performance and fast response speed, compared with traditional PID control er.%为实现机电伺服系统的高精度位置跟踪控制，针对实际系统运行过程中所存在的转动惯量和负载力矩变化大等各种不确定因素，提出了一种基于滑模面的自适应模糊PID策略。利用梯度下降法实时修正PID控制器的参数，使用模糊逻辑系统逼近系统中不确定量，以使控制器能根据伺服系统运行过程中的负载特性实时调整速度给定值，从而减小系统参数变化和外部干扰对伺服系统性能的影响，最后通过Lyapunov方法推导出了模糊补偿器中不确定参数的自适应律。仿真结果表明：该控制策略与传统PID控制相比具有系统跟踪误差小，响应速度快，跟踪性能好的优点，对参数摄动及外界负载扰动具有较强的鲁棒性。