Self-tuning fuzzy PID controller for non-linear and higher-order processes

Abstract

We propose a self-tuning fuzzy PID controller (STFPIDC) for non-linear and higher-order processes with dead time whose output scaling factor (SF) is continuously adjusted in each sampling instant by a non-fuzzy gain modifying factor γ, which is defined on the sign of error and change of error of the controlled variable, and the number of their uniform fuzzy partitions. Performance of the proposed controller is studied for non-linear and higher-order processes with dead-time under both set-point change and load disturbance. Performance comparisons with other FLCs are provided in terms of various performance indices along with transient responses. Simulated results justify the effectiveness of the proposed STFPIDC.