Application of Open-Circuit IGBT Faults Diagnostic Method in DTC-SVM Induction Motor Drive

In this paper a simple diagnostic method of a single IGBT open-circuit fault is presented, it is dedicated for three-phase two-level voltage-inverter-fed vector controlled induction motor drive systems. A failure diagnosis is based on a transient analysis of a reference voltage space vector in stationary coordinates, without additional sensors. The diagnostic algorithm ensures detection and localization of single IGBT failures in time shorter than one period of a stator current fundamental harmonic, without regard to a drive operation point. The presented scheme of the diagnostic system can be easily applicable in the electric drives that use voltage space vector modulation algorithms. The main achievement of the research, whose results have been presented in this paper, is an experimental validation of the analyzed IGBT faults diagnosis technique in the drive with the Direct Torque Control algorithm.