模糊自适应PID算法在磁悬浮实时控制系统中的应用研究

摘要

针对磁悬浮系统的复杂非线性及模型不确定的特点,采用模糊PID算法对其进行控制,以满足系统对动态性能和静态性能的要求;结合PID实时控制中的经验,建立合理的模糊规则,模糊推理机构根据不同的偏差e、偏差变化率ec对PID参数Kp、Ki和Kd进行自校正;在磁悬浮实验装置中进行实时控制实验,通过与常规PID控制效果的比较来验证模糊PID控制器的性能;在系统输入存在正弦扰动时,模糊PID控制器使系统响应过程中的振荡幅度得到明显减小,干扰对控制效果的影响被减弱;实验证明,模糊PID控制器具有较强的鲁棒性和抗干扰能力,对于磁悬浮这种非线性系统具有良好的控制效果.%Aiming at the characteristics of the complex nonlinearity and uncertain model, fuzzy PID algorithm is adopted to satisfy the requirements of dynamic and static performance in the control of magnetic levitation system. Based on the experience in the real time PID control experiment, fuzzy control rules are established. According to different deviation e and deviation rate of changeec. , PID parameters Kp , K, and KdWere accomplished self tuning by fuzzy inference mechanism. The real- time control experiment is done in the magnetic levitation device in order to verify the control performance of fuzzy PIDconlroller. When system input exists sinusoidal disturbance, the oscillation amplitude cif the system in response process and the impact of interference are reduced obviously by fuzzy PID controller. The experiment proves that this fuzzy PID controller owns better robustness and stronger anti - interference and has good control performance for the nonlinear system such as magnetic levitation system.