Characterization analysis of effects in an induction motor on asymmetrical operation

This paper develops the foundations of a technique for characterization of effects of broken bars in squirrel-cage induction motors based on the Time-stepping coupled Finite Element approach. These studies are performed by using the model to compute healthy case, one broken bar fault and two adjacent broken bars fault performance data. A finite element model of a stator-rotor coupled thermal field over the whole cross section of the induction motor is created. At the above three states the steady stator-rotor coupled thermal fields of the motor with normal full load are calculated respectively. Then the influence of the number of broken bars on the motor thermal field is analyzed. From the variations of the motor thermal fields, some valuable idea can be proposed to the broken bars faults diagnosis.