Design and analysis of a novel stator hybrid excited doubly salient permanent magnet brushless motor

Abstract

Permanent magnet (PM) machines have been used widely for industrial applications. However, the operating speed range in most of these applications is very limited due to the difficulty of achieving field weakening in most PM machines. In this paper, a novel 12/8-pole stator hybrid excited doubly salient permanent magnet (SHEDS-PM) brushless motor capable of field weakening is proposed. By using 2-D finite element method, the corresponding static characteristics are deduced. Based on the operation principle and the static characteristics of the motor, the steady-state and dynamic models and computer simulation of the proposed 12/8-pole SHEDS-PM motor are also presented in the paper. It is shown that by controlling the field winding, flux weakening (or boosting) capability can be easily obtained due to the special motor structure with a magnetic bridge. This feature makes the motor a potential candidate motor in drive systems.