Comparative investigation of fault indicators for synchronous machine failures

Abstract

Ideal condition of a synchronous machine and subsequent fault models representing rotor eccentricity of different types as well as inter-turn short circuits in stator and rotor are created with finite element method simulation for a specially designed SM. This machine has provisions of recreating the same faults made in the simulations by suitable changeover of customized end-shields and sleeves in the shaft assembly for various eccentricity faults or introducing short circuits through accessible terminals of the stator and rotor windings. The fault indicators for characterizing such failures are identified and are measured through experiments. Clear difference obtained between separate fault signatures help identifying and discriminating rotor and stator related failures. With fair understanding of geometry, physical dimensions and the ability to model the complex portions of healthy as well faulty conditions, such a concept helps to create a know-how to detect different failures, well before a catastrophic event takes place.