Self-tuning fuzzy PI controller for integrating and non-linear processes

For integrating, non-linear and higher order processes with dead time conventional non-fuzzy controllers usually provide poor performance than Fuzzy Logic Controllers (FLC). We propose a self-tuning fuzzy PI controller (STFPIC) for integrating and non-linear processes with dead time where 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, continuously adjusts the output scaling factor (SF) in each sampling instant. Performance of proposed controller is studied for integrating and non-linear processes with dead-time under both set-point change and load disturbance. Results show the effectiveness of the proposed STFPIC in set-point change as well as load variation.