PID-fuzzy controllers with dynamic structure and evolutionary method for their construction

Abstract

The controllers are interesting type of information systems. Their structure and parameters for atypical applications usually are selected by trial and error method, which can be time-consuming. In this paper a controller structure, which is an ensemble of PID controller and fuzzy system, and an automatic evolutionary method for its construction is presented. The significant feature of proposed method is that the controller elements, that increase its complexity but do not improve the controller precision in the sense of the adopted evaluation function, can be reduced. Moreover, this method allows to use the knowledge of the controlled object. A typical control problem has been used to test the authors approach.