SPEED SENSORLESS CONTROL OF PERMANENT MAGNET SYNCHRONOUS MOTORS USING SLIDING-MODE OBSERVER

Abstract

This paper presents a method for Permanent magnet synchronous motor
(PMSM) drive using Field-Oriented Control (FOC) technology. The rotor speed
and current tracking controllers are designed based on backstepping control
theory. A Sliding-mode observer (SMO) is used to estimate the back
electromotive force under a static frame. After that, a Phase-locked Loop (PLL) is
designed to estimate the speed and position of the rotor. The SMO and PLL have
robustness against disturbance, high accuracy estimation ability. Moreover,
speed and current tracking performance may be affected significantly by the
disturbance which is caused by parameter variations and external load torque. So
another SMO is presented to estimate the lump disturbance and improve the
robustness of the controllers. Finally, the simulation and results are
implemented using Matlab/Simulink with Siemens 1KF7 PMSM.