Design and Implementation of a GPC-Based Auto-Tuning PID Controller

PID control schemes have been widely used in most process industries. Since the control performance strongly depends on PID parameters, it is important to suitably choose a set of these parameters. Especially, it is difficult to determine these parameters in the case where the time-delay is unknown and/or large. On the other hand, it is well-known that the generalized predictive control(GPC) effectively works for such systems. Then, a new PID tuning scheme(GPC-PID) which is derived from the relationship between the GPC and the PID control laws is proposed in this paper. Furthermore, the implementation of the GPC- PID for the existing PID auto-tuner is considered. A consideration on determining the user-specified parameter included in the GPC-PID, is also considered. Finally, the GPC-PID is tentatively implemented in the existing thermoregulator, and the behavior is experimentally examined.