STATOR CURRENT ANALYSIS OF INCIPIENT FAULT INTO ASYNCHRONOUS MOTOR ROTOR BARS USING FOURIER FAST TRANSFORM

Arezki Menacer - Mohamed-Saïd Naît-Saïd - A/Hamid Benakcha - Saïd Drid

   Recently, research has picked up a fervent place in the area of fault diagnosis of electrical machines. Like adjustable speed drives, fault prognosis has become almost indispensable. Motor current signature analysis is a condition monitoring technique that is now widely used to diagnose problems such as rotor bars broken, abnormal levels of air gap eccentricity, shorted turns in low voltage stator windings, and some mechanical problems.

    This paper presents the effect of the broken bar time evolution since the created incipient fault on the various characteristics of the induction machine such as torque, speed and current. This one is simulated while the rotor bar resistance may be varied linearly versus time since its normal value to the final broken bar situation (partial to total broken bar). In this way we can observe the incipient fault impact on the different characteristics of the machine quantities (torque, speed and current).

Keywords: fault simulation, mathematical models, condition monitoring, asynchronous (induction) motors, incipient broken bar, resistance bar, resistance time ratio

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