Rotor Inter-turn Short-circuit Fault Diagnostics Relevant Modeling of Slip-Ring Induction Motor

Many slip-ring induction motor (SRIM) models are found in the literature. In this paper, new extended state-space slip-ring induction motor models are developed using reference frame theory. All these SRIM models are investigated regarding their diagnostic relevance to rotor turn-To-Turn short-circuit fault. Ability to generate distinct residuals is important for any model-based fault diagnostics. The performance of these models in term of their capability to detect a fault is compared and best-suited models are recommended based on discriminatory ability index presented in this paper. Analytical computations are carried out for a 4-hp four-pole slip-ring induction motor using MATLAB software. Simulation results are presented to illustrate and validate the proposed index