An improved indirect field-oriented controller for the induction motor

In this paper, the standard indirect field-oriented controller (IFOC) commonly used in current-fed induction motor drives is modified to achieve global exponential rotor velocity/rotor flux tracking. The modifications to the IFOC scheme, which involve the injection of nonlinear terms into the current control input and the so-called desired rotor flux angle dynamics, facilitate the construction of a standard Lyapunov stability argument. The construction of a standard Lyapunov exponential stability argument allows one to easily design adaptive controllers to compensate for parametric uncertainty associated with the mechanical load. Simulation results are included to illustrate the improvement in performance over the standard IFOC scheme.