PID TYPE FUZZY CONTROLLER AND PARAMETERS ADAPTIVE METHOD

The authors of this paper try to analyze the dynamic behavior of the p roduct-sum crisp type fuzzy controller, revealing that this type of fu zzy controller behaves approximately like a PD controller that may yie ld steady-state error for the control system. By relating to the conve ntional PID control theory, we propose a new fuzzy controller structur e, namely PID type fuzzy controller which retains the characteristics similar to the conventional PID controller. In order to improve furthe r the performance of the fuzzy controller, we work out a method to tun e the parameters of the PID type fuzzy controller on line, producing a parameter adaptive fuzzy controller. Simulation experiments are made to demonstrate the fine performance of these novel fuzzy controller st ructures.