| Abstract |
In the past, Variable Structure Control with Sliding Mode (VSC-SLM) has been successfully applied to versatile control applications, in which robustness against parametric variations and external disturbances are guaranteed. Therefore, it is usefully employed in systems with uncertain and time-varying parameters such as the induction motor (IM) drive. However, with the heritage of past control experience, the chattering effects about the sliding surface remains a major concern and as a result it has limited its practical application in high performance drive systems. This paper presents a method to introduce fuzzy logic algorithms into the design of VSC-SLM, in order to alleviate the chattering problems and to improve the dynamics of the IM drive. The theoretical bases for this algorithm are given, and a concrete scheme for constructing the proposed control system is presented. A computer model for the proposed controller is constructed and simulated when it is applied to the outer loop speed control of an IM drive. The proposed method has achieved a considerable improvement of the drive dynamics in contrast to those obtained with the conventional VSC-SLM. |
