Diagnosis of Dynamic Eccentricity Fault in Inverter-Fed Induction Machine Using Three Phase Stator Currents Intersection Signal

The current research presents a dependable and practical indirect approach for detecting and diagnosing Dynamic Eccentricity in inverter-feed induction machines operating at varied load circumstances. The spectral analysis of the Three Phase Currents Intersection Signal (TPCIS) and its positive envelope is the main focus of the suggested technique. The sinusoidal TPCIS signal is extracted from finding time and amplitude of each positive and negative intersection point in three-phase stator current signals rather than using the classical Zero Crossing Time Approach (ZCTA), and the TPCIS signal is formed through searching and interpolating all the crossing points. The positive envelope of TPCIS can be obtained through spline interpolation of all positive crossing points. The theoretical foundation of the suggested technique is presented, and it is then experimentally confirmed by testing two induction machines: one healthy for comparison, and the other with Dynamic Eccentricity fault (DEF). Each machine is exposed to two loads (low, and high load). The acquired experimental findings illustrate the resilience and usefulness of the suggested approach, as well as its capacity to distinguish defective cases from healthy ones under varied load conditions, even at low load.