Reduction of Radial Magnetic Force Waves Based on Eccentric Magnetic Pole for Claw Pole Alternator

Electromagnetic vibration is produced by radial magnetic force waves acting on stator core of claw pole alternator. This paper analyzes the magnetic vibration and noise of mobile claw pole alternator. A new effective method to reduce radial magnetic force for claw pole alternator was proposed based on eccentric magnetic poles. The expressions of eccentric pole magneto motive force Fourier transform were established. The relationship between the radial magnetic force amplitude and the eccentric distance was acquired. It is shown that according to the suitable eccentric magnetic poles, the radial magnetic force and noise can be reduced. The finite element method results and experiment test verified the availability of the proposed method.