New design in order to reduce rotor reaction for squirrel cage induction motor: Skewed slits

Abstract

In this study, a new design has been developed to reduce the rotor reaction generated in squirrel cage induction motors. In this new design, slits have been opened between the slots of the stator and rotor, and the resulting change in the rotor reaction angle between these slits and the stator and rotor flux lines has been then investigated. Comparisons have been made between the rotor reaction angle values obtained with the without slitted and slitted models; in case these slits have been skewed right or left, the change in the rotor reaction angle has evaluated as well. According to the study results, the use of the slitted structure reduced the rotor reaction angle by 39.42%. In addition, we have observed that in case the slits were skewed right (by 6o), the rotor reaction angle has decreased by 45.67%. On the other hand, in case the slits were skewed left, the rotor reaction angle has tended to increase. The Finite Element Method Magnetics (FEMM) program has been used to determine the distribution of the magnetic fields.