Comprehensive Investigation of Harmonic Signatures Resulting from Inter- Tum Short-Circuit Faults in DTC Driven IM Operating in Harsh Environments

In this paper the harmonic components in the stator's current and the developed torque of a faulty induction machine (IM) driven by Direct Torque Control (DTC) is investigated. The fault under consideration is the inter-turn short-circuit (ITSC) in stator's winding. Deep study of the harmonic and inter-harmonic content is conducted for fault detection (FD) purposes. The harmonics in the spectrum appear as a result of diverse causes including stator fault, DTC reaction to the fault, switching activities of the inverter, core saturation effect, and noise signal for IM operating in harsh industrial environment. Simulation reinforced by experimental results demonstrated the correctness of the frequency domain analysis.