Monitoring of stator inter-turn short circuits in the direct field oriented controlled induction motor

This paper deals with monitoring and diagnosis of stator windings damages in vector-controlled induction motor (IM) drive. The article proposes a simple method of shorted turns detection using only virtual control and decoupling signals from the classical Direct Field Oriented Control (DFOC) method. The diagnosis of the stator windings faults is based on the analysis of twice the fundamental frequency of mentioned signals. The proposed method is illustrated using experimental test results obtained for 1.5 kW induction motor, especially prepared to allow physical modelling of shorted turns.