motor-armature
9.Abstract: First,the key magnet statuses and their pertinent MMF.position of exterior rotor brushless DC motor are described in this paper.Second,the air-gap magnetic field and the armature reaction of the three-phase six-step exterior rotor brushless DC motor used in electrical bicycle are analyzed by means of MMF.vector,MMF.integration and magnetic field FEM respectively.Some valuable conclu-sions for designing this kind of motor are obtained.

