Adaptive sliding-mode control for induction servomotor drive

An adaptive sliding-mode control system is proposed to control the position of an induction servomotor drive. First, a newly designed total sliding-mo de control system, which is insensitive to uncertainties including paramete r variations and external disturbance in the whole control process, is intr oduced. The total sliding-mode control comprises the baseline model design and the curbing controller design. In the baseline model design a computed torque controller is designed to cancel the nonlinearity of the nominal pla nt. In the curbing controller design an additional controller is designed u sing a new sliding surface to ensure the sliding motion through the entire state trajectory. Therefore, in the total sliding-mode control system the c ontrolled system has a total sliding motion without a reaching phase. Then, to relax the requirement for the bound of uncertainties, an adaptive slidi ng-mode control system is investigated to control the induction servomotor. In the adaptive sliding-mode control system a simple adaptive algorithm is utilised to estimate the bound of uncertainties. Simulated and experimenta l results due to periodic sinusoidal command show thai the dynamic behaviou rs of the proposed control systems are robust with regard to uncertainties.