一类不稳定系统的PID控制器整定

Tuning of PID controller for unstable plant systems

借助系统辨识的思想,改进了基于预期动态法的二自由度PID控制器(DDE-PID)的参数整定过程,并将其应用到不稳定系统上。采用先PD稳定对象,然后根据PD稳定后的控制对象的开环阶跃响应曲线即可得到所需参数,该方案具有参数整定过程简洁、实用性强、不依赖于精确模型等优点。针对改进前后的DDE-PID控制方案,选取4个典型的不稳定对象,分别与设定值跟踪实验和蒙特卡洛实验做了对比。仿真结果表明,本文所提方法对不稳定对象简单易用,在保证较好的控制性能的条件下,具有较好的鲁棒性,同时该方法可以根据需要方便地进行参数调整,实用性强。

According to the idea of system identification,two degree of freedom PID based on desired dynamic equation（DDE-PID）has been improved.In this paper,DDE-PID has been applied in unstable plant systems.This method adopts a PD controller first,and then,the required parameters can be obtained in accordance with the open-ring step response curves after PD stable control object,and it has advantages in simple tuning,better practicability and does not rely on the accurate model of plant.With an aim at the improved DDE-PID control scheme,the 4typical unstable objects are selected to carry out the contrast of the set value tracking experiment with Monte-Carlo experiment.The simulation results indicate that the method suggested in this paper is simple and easy to be used in the unstable objects,and has had the better robustness in the case of guaranteeing better controlling performances,meanwhile this method can regulate the parameters based on the requirements conveniently and with better practicity.