An fem-based analysis of impacts of rotor slots numbers in the characteristics of medium rated squirrel cage induction motor

Abstract

Rotor slots play an important role in the performance characteristics of squirrel cage induction motors. Not only the rotor slot geometry parameters but also number of rotor slots considered for the modelling of rotor highly influence the performance indicators and parameters. The number of rotor slots effect the equivalent circuit parameters, performance indicators, magnetization characteristics, and flux distribution of the SCIM. In this research work, for a fixed value of number of stator slots, four possible values of the rotor slots such as 28, 30, 32, and 34 are considered for the performance analysis of SCIM. A medium-rated general-purpose SCIM with 3 kW, 50 Hz, and 400 V is modeled in finite element-based Ansys Electronics Desktop software platform. The RMxprt design of the motor is used for the performance comparison of SCIM, and the analysis is extended to Maxwell2D design analysis to investigate flux distributions in each case of the number of rotor slots. The results show that the number of rotor slots significantly impacts the overall performance of the SCIM. In addition, the rotor slots of 28 and 30 provide better performance in terms of performance indicators, magnetic characteristics, and flux distributions while the rotor slots of 32 and 34 offer better breakdown torque.