A PID autotuner utilizing GPC and constraint optimization

This paper offers a solution to the PID autotuning problem, by constraining the parameters of a discrete 2nd order discrete-time controller. The integrator is forced into the regulator by using a CARIMA model. The discrete-time regulator parameters are calculated by optimizing a GPC criterion, and the PID structure is ensured by constraining the parameters to a feasible set defined by the discrete-time Euler approximation of the ideal continuoustime PID controller. The algorithm is extended by incorporating constraints in amplitude and slew-rate of the control signd. Generality is discussed, and some of the significant properties of the algorithm is shown by simulations.