On a Class of Control Systems with Takagi-Sugeno PI-Fuzzy Controllers

The paper proposes a new development method dedicated to a class of fuzzy control systems containing Takagi-Sugeno PI-fuzzy controllers to control SISO linear / linearized plants. The considered controllers are characterized by variable number of triangular input membership functions. The method is expressed in terms of relatively simple steps that use the prediction of the limit cycles on the basis of the gain-phase margin analysis and on the design results from the linear case. The method is applied to the development of a class of PI-fuzzy controllers for servo systems, and it is accompanied by the sensitivity analysis with respect to the parametric variations of the controlled plant and validated by a case study.