Fuzzy supervision of direct controllers

In closed-loop control systems, a supervision loop is sometimes needed in order to perform an operation task which usually consists of adjustments of set points and controller parameters. A fuzzy approach to the supervision of controller parameters in single-loop plants is described. The fuzzy supervision is performed over two different direct controllers: a PI (proportional-integral) and a fuzzy controller. The results of experiments conducted to test the supervision strategy with two different simulated systems and one scaled pilot plant are presented. In the fuzzy controller, the central values of the rules output membership functions are adjusted at the supervision sampling instants. For the PI controller, the adjusted parameters are the proportional and integral gains