NOVEL SPEED SENSORLESS INDIRECT FIELD-ORIENTED CONTROL OF INDUCTION MOTOR USING PLL AND EKF

Abstract

This paper presents an improved method of stator angular (frequency) θ_s estimation for sensorless indirect oriented field control of induction motors based on a phase locked loop (PLL). A PLL is used to estimate the stator Voltage angular taking account only the reference speed. A extended Kalman Filter (EKF) is used to estimate speed and rotor flux. Extensive simulation and experimental tests confirm the effectiveness of the proposed approach.