Optimal sliding mode control of asynchronous machine speed with state feedback

A novel methodology which is convenient for the design of optimal sliding-mode control for an asynchronous machine drive is developed. A suitable model of the induction machine control system, incorporating the counter-EMF (electromotive force) under field orientation, is presented. Analytic solutions for the optimal switching vector C, and the feedback matrix, L in unit-vector sliding-mode control are obtained. The optimal synthesis is directly related to the desired system specifications in the time domain without the necessity of solving the Riccati equation or complicated matrix equations. This greatly simplifies the conventional complicated design procedure and improves the design quality. Simulation and experimental results verify the optimal design.<>