Adaptive Stable PID Controller with Parallel Feedforward Compensator

In this paper, a new design method of adaptive PID controller is proposed. The method utilizes the plant characteristics called almost strict positive realness (ASPR) so that the stability of the adaptive PID control system is always guaranteed. The design scheme is derived for the design of adaptive tracking PID control system. Here it is also proposed a new design procedure of the parallel feedforward compensator (PFC) which actually guarantees the ASPRness of the controlled plant. The result is examined by applying it to the design of the first order with time delay process system. The effectiveness of the method is examined through simulations and experiments using thermal pilot plant