Optimal design of a hybrid excitation claw-pole alternator based on a 3-D MEC method

Output performance optimization of a hybrid excitation claw-pole alternator is presented using a three-dimensional (3-D) magnetic equivalent circuit (MEC) method taking the nonlinear magnetic properties of iron into account. A 3-D MEC model of the hybrid excitation alternator is presented. On this basis, the dimensions of permanent magnets and the output currents are optimized using genetic algorithm and the optimization results are presented.

I. Introduction

Claw-pole alternators are widely used as generators in automobiles. The shape of the claws leads to a truly 3-D magnetic field in all regions. Consequently, for the correct calculation of magnetic field and alternator characteristics, a 3-D numerical method is required. The finite element (FE) method requires a large calculation time. The MEC method requires less calculation time and can retain high computational accuracy. Reference [1] gives performance computation results of a conventional claw-pole alternator using the 3-D MEC method.