Design and Analysis of Electric-Excitation Claw-Pole Field-Modulated Machine Considering Effective Harmonics
Xianglin Li, Xiaosong Wang, Yu Dong, Kejin Lu, Xingtian Feng
Abstract
This paper presents a multi-objective optimization design method for an electric-excitation claw-pole field-modulated (EECPFM) machine, which employs a ring-shaped excitation coil in the stator cavity formed by the claw poles, thus eliminating the slip rings and brushes, and improving the operation reliability. Due to axial asymmetry, the traditional optimization design based on 3-dimensional finite element analysis (3D-FEA) is time-consuming. The key of the proposed optimization method is to incorporate the air-gap field harmonic characteristics into the EECPFM machine design, namely, by taking the main air-gap field harmonics having strong influence on torque capability and torque ripple as multiple optimization objectives, and combing the response surface (RS) model and the artificial bee colony (ABC) algorithm to implement the optimization process, thus saving time. Subsequently, with the help of 3D-FEA, the electromagnetic performance between the initial and optimal structure are compared, i. e. 12% torque improvement and 2.8% ripple suppression. Finally, a EECPFM prototype is fabricated and the validity of the proposed optimization design is evidenced by the experiments.