Abstract:
In the design of control systems, the model identification error of a physical system will affect the performance of the designed system. To solve this problem, we propose a proportional-integral-derivative (PID) parameter tuning method based on the closed loop response property. After analyzing the frequency properties of a PID controller, we propose the concept of characteristic frequency of a PID controller to build a relationship between the PID parameters and the frequency properties of a PID control system. Then we give the PID parameter tuning rules based on the characteristics of closed loop response. The main merit of these tuning rules is that only the characteristics of the closed loop response of the control system are required in the tuning process, while the system model of the controlled object is not needed. Using the proposed method, simulations are conducted to design control systems for typical models. The simulation results show that the step response of the designed system is quick without overshot, and its disturbance suppression is very effective. Thus the effectiveness of these tuning rules is verified.