Model-Free PI/PID Controller Tuning of Higher Order Nonlinear Dynamic Systems

Abstract

This paper concerns model-free PI/PID controller tuning of possible (nonlinear) higher order systems. The method can be considered as a three-step procedure. The first step is to persistently excite the system in open loop and identify the dynamic model using a subspace identification method. The second step is to approximate the model to an integrator plus time delay or double integrator plus time delay dynamic model. The third step is to compute the PI/PID controller parameters. The proposed method/theory is verified on some motivated nonlinear higher order dynamic models.