A closed loop observer for rotor flux estimation in induction machines

Abstract

Flux estimation in induction machines is presented using observer theory. It is pointed out that estimators presently used in connection with schemes such as field oriented control are typically real time simulation of machine equations, without feedback of any corrective prediction error. Design steps in a closed loop observer with prediction error correction term are presented. It is shown that corrective feedback in closed loop observer speeds up convergence of the flux estimate.