A discrete-time sliding mode controller and observer with computation time delay

Abstract

Based on discrete-time sliding mode, a robust controller and an observer that consider computation time delay are presented. The computation time delay is assumed to be constant and smaller than the sampling time. To cancel out the effects of perturbation, the proposed controller uses the concept of Time Delay Control (TDC). In the design of the observer, the concept of the discrete-time equivalent control approach is adopted. Furthermore, the combined controller–observer system is investigated. The usefulness of the proposed controller and the observer is demonstrated through experiments on a direct drive motor.