Enhanced VRFT design of adaptive PID controller

In this paper, an enhanced virtual reference feedback tuning (EVRFT) design method with specific application to adaptive PID controller design is developed. The proposed EVRFT design is an extension of conventional VRFT design and adaptive VRFT (AVRFT) design previously developed in the literature. The EVRFT design makes use of a second-order reference model instead of the first-order reference model used by both VRFT and AVRFT designs. In addition, unlike the AVRFT design, the parameter of reference model in EVRFT design is updated at each sampling instant to further enhance the performance of resulting adaptive PID controller. Simulation results demonstrate that the adaptive PID controller using the proposed EVRFT design gives better response than those obtained by the VRFT and AVRFT designs.

► A new adaptive PID controller design method is developed using the proposed EVRFT method. ► EVRFT design generalizes previous results of both VRFT design and adaptive VRFT design methods. ► Reference model of EVRFT design is updated to enhance the performance of adaptive PID controller. ► Simulation results show better performance of EVRFT design compared with its counterparts.