Stator winding inter-turn fault in induction machines: Complex-vector transient and steady-state modelling

摘要

This paper presents a complete development of the complex-vector (CV) state-space (SS) representation of squirrel-cage induction machine (IM) with an inter-turn short-circuit (ITSC) in one phase of the stator winding. The final representation of the model can be decoupled in two modes: “Common Mode” and “Differential Mode” and it is the presented in its simplest form. From this faulty model a CV and operation equivalent circuits (EC) are determined. The model is fully simulated for transient and permanent regimens by means of MatLab code solving the ordinary differential equations (ODE). The steady state ECs were simulated in Simulink. Additionally, the sequence components admittances matrix and EC for the faulty IM was inferred for purposes of fault detection and identification (FDI). The effect of the fault severity factor and fault resistance are tested over the faulty leakage current, torque ripple pulsations and space vector current components. Finally, the torque vs slip characteristic curve were examined under input voltage and frequency variation to observe the loading effects on the faulty IM model.