Vector control for induction motor based on minimum variance controller

A new technique for the speed control of a three-phase induction motor (IM) based on a minimum variance controller (MVC) is proposed in this paper. The IM model is derived in a synchronously rotating reference frame using the vector method. This model comprises three input variables and three output variables, and the objective of the proposed controlled system is to achieve rotor speed control, field orientation control and constant flux control. The parameters of the controlled system are estimated online by the least squares algorithm with the reference model including the nominal values of the rotor angular velocity and the two components of the rotor flux linkage current. The design procedure of the MVC, parameters estimation and construction of the ARMAX model for the IM are investigated. Extensive simulations are made to illustrate the tracking performance, robustness and the applicability of the proposed stochastic adaptive control system.