Design of an explicit constrained predictive sliding mode controller

This article presents a generalised predictive controller with improved performance and robustness by means of a reaching law to force a pseudosliding dynamic behaviour. This work has been motivated first by the existence of many industrial non-linear processes that can be well approximated by first-order plus dead time models. Thus, an explicit control law can be obtained, which overcomes some of the disadvantages of traditional sliding mode control and generalised predictive control strategies. Moreover, the necessity of providing the operators with useful values for a controller first tuning computed from the modelled pole and delay is also satisfied. Some simulation examples show the good characteristics of the proposed controller, coping with modelling errors, constraints on the control variable and on the manipulated variable, and time-varying delays.