A Saturated PI Velocity Controller for Voltage-Fed Induction Motors

The paper by Hernandez-Guzman and Santibanez is an interesting contribution to the induction motor field oriented control (FOC) literature. Standard FOC schemes can only prove local asymptotic regulation to the speed and flux references. The authors modify the classical indirect voltage-fed FOC methodology and propose the use of a saturated PI velocity control loop to ensure global asymptotic regulation. Two variations of the original scheme will be presented in this discussion note. The first one, addresses the following question: can we select a reference torque τ ∗ such that for the simple PI control law (19)