Adaptive sliding-mode control for induction servomotor drive

An adaptive sliding-mode control system is proposed to control the position of an induction scrvoniotor drive. First, a newly designed total sliding-mode control system, which is insensitive to uncertainties including parameter variations and cxternal disturbance in the whole control process, is introduced. 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 tlie nominal plant. In the curbing controller design an additional controller is designed using a new sliding surface to ensure the sliding motion through the entire state trajectory. Thercfore, in tlie total sliding-mode control system the controlled system has a total sliding motion without a reaching phase. Then, to relax the requirement for the bound of uncertainties, an adaptive sliding-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 experimental results due to periodic sinusoidal command show t l d the dynamic behaviours of the proposed control systems are robust with regard to uncertainties.