A Simple Sensor-less Vector Control System for Variable Speed Induction Motor Drives

Abstract

This paper demonstrates a new and simple speed estimation method for the induction motor (IM) drives at low speeds. This method uses the current and the input voltage in a closed loop for rotor parameter estimation. In this method, a digital system expression is considered where we assume that the rotor flux and the rotating speed are constant during a short sampling period. Simulation and experimental results demonstrate the validity of the proposed estimation algorithm for practical applications.