A Simple, Robust and Non-Intrusive Technique of Efficiency Determination of In-Service Induction Motors

Abstract

In-situ induction machine (IM) efficiency estimation is an essential tool for improved performance and better distribution management. IN industrial scenario, working efficiency of IM is affected by operation of IM at loads much less than rated loads and the impact of rewound or repair. In this paper, a simple, robust and non-intrusive technique of efficiency determination of in-service IMs utilizing non-intrusive air-gap torque method is proposed which considers stray-load and friction-windage loss as per IEC 60034-2-1:2007 Standard. This approach eliminates the need of speed sensor as well as torque sensor. The proposed method is simulated using MATLAB/SIMULINK and supported with experimental results.