Performance Analysis of Double Cage Induction Motor with Broken Bar Faults in Outer Cage

Abstract

Induction motors are one of the most commonly used motor in the industry. For this reason, a fault (electrical or mechanical) inside or outside of the motor can cause the motor to go out of power and even cause the production losses inside the factory. Although there are many studies on single-cage induction motor failures in the literature, double cage motor failures are not a frequent subject of study. Therefore, in this study, it was investigated how the outer cage slot faults in a double cage induction motor affect the motor performance. Analyses were performed using Finite Element Method (FEM). 1, 2, 3 and 4 outer cage broken bars in the rotor slot were investigated. Rotor currents, magnetic vector potential values, magnetic flux distributions, current densities, radial forces and torque-speed graphs of the motor models were obtained and compared for both healthy and failure motors. The results show that as the number of broken bar in the rotor increased, a significant reduction was observed in all three torque (starting, maximum and nominal) values. It has been observed that the starting torque decreased by 13.77% for the 4 broken outer cage rotor bars motor according to the healthy motor.

Keywords

• broken bars
• finite element method
• induction motor
• outer rotor cage fault
• performance analysis