Torque and Radial Forces of Switched Reluctance Motor

Abstract

A Switched Reluctance Motor has a doubly salient structure, both stator and rotor have saliency and it has an advantage in a harsh environments due to a simple and robust structure. However, it has the disadvantage that the motor is noisy because of deformation of the motor by the radial force. This paper examines the radial force for various types of SRM at a constant mmf or constant torque using the two dimensional finite element method. We propose the evaluation factor of the acoustic noise using the finite element analysis. It is cleared that the torque is produced at the oncoming pole edges and the radial force yields at the pole face. The evaluation factor of the acoustic noise in an experimental result agrees well with the calculation value. As a result, the suitable type SRM expecting low noise is 12/8 type.