Stator inter-turn fault analysis of reluctance synchronousmotor

Abstract

Stator inter-turn fault is one of the most common faults occurring in electric motors. Detection of stator inter-turn faults at their incipient stages can prevent catastrophic failure of the machine and the consequent down time. In this paper, the stator inter-turn fault analysis of the reluctance synchronous motor (RSM) has been considered under steady-state operating condition. Detailed modeling of motor with inter-turn fault in one of the phases of the stator winding has been carried out using modified winding function approach (MWFA). Initially, motor current signature analysis (MCSA), a very useful tool in the condition monitoring of electrical machines, has been used to analyze the performance of the motor in presence oft such faults It is evident from the initial study that odd triplen harmonics increase in the line current of RSM with inter-turn fault as it disturbs the symmetry of the machine. The line current of the faulty phase also increases with more number of shorted turns. A relative comparison of the magnitudes of odd triplen harmonics has been presented with different number of faulty turns along with the line current of the faulty phase. In order to validate the theoretical results, the experiments with inter-turn shorts have been conducted on a rewound machine with taps. The increase of 9th harmonic seems to be most promising