Operating Induction Machine in DFIG Mode Including Rotor Asymmetry

Abstract

This paper develops a model for accurately analysing the behaviour of a wound rotor induction machine, which are often used as doubly-fed induction generators, with rotor faults. Variations in the amplitude of stator current components are used to detect these faults, including electrical asymmetry of the external-connected rotor resistances of a four-pole wound rotor. The steady state performance was investigated by means of an equivalent circuit which includes the rotor asymmetries. It is tested successfully on a three-phase balanced and unbalanced induction machine.