A nonlinear PID-type controller utilizing fuzzy logic

This paper presents a new controller model, the fuzzy-PID controller, which merges PID control and fuzzy control in order to improve system performance especially when nonlinearity, uncertainty and complexity are involved. The proposed model provides a mechanism to achieve PID control selftuning and encodes different control strategies for use under different circumstances in a fuzzy rulebase. The rulebase can be adapted to different plants through successive refinement learning. The derived controller can always equal or better the performance of any PID controller. The new structure is implemented for several plants and demonstrates significant improvements in system performance