Electromagnetic Torque and Force Analysis of Switched Reluctance Motors with Different Rotor Pole Shapes

In this paper, analysis of the torque ripple and radial force reduction by different rotor pole designs of a three-phase 6/4 switched reluctance motor is presented. In order to improve torque performances by changing stator and rotor angles for three-phase switched reluctance motors, many papers have recently used the types of stator and rotor poles, with 6/4; 8/12; 18/12 and 24/18. Improvement of the average torque and torque ripple have influenced directly on rotor poles designs, because flux density distribution at the air gap will affect torque performance and radial forces. Several rotor tapped-skew poles have been calculated for the three-phase switched reluctance motor by the finite element method to give suitable results. The efficiency, average torque and torque ripples have been simulated and analyzed. A significant distribution of this research is to implement the skew-tap rotor pole with the optimal tap-angle for maximizing torque ripple and radial forces. The improvement of method is validated on the practical problem, with a switched reluctance motor of 30 kW.