Sensorless Sliding Mode Vector Control of Three Phase Induction Motor Drives

Abstract

In this thesis work, an indirect vector control of induction motor drive with a sliding mode controller is presented. The design consist of rotor speed estimation from measured stator terminal voltages and currents. The estimated speed is used as feedback in an indirect vector control of induction motor to achieving the speed control without the use of shaft mounted transducers. The specific contributions of the thesis are, first, a new sliding mode speed controller is developed by delicately introducing a switching variable and a design parameter. Then a fixed gain PI controller is also designed to compare the result. Combining the sliding mode controller and PI controller, the results are thoroughly analyzed to check the robustness of controller, reference speed tracking performance and regulator performance. Then, the robustness of the proposed sliding mode controller scheme is effectively demonstrated by considering standard inertia and high inertia load. Finally the speed is estimated by the rotor flux observer to realized sensorless control of induction motor drive.