volume | PIER Journals

Abstract

To address the inherent significant average torque degradation in conventional Axial Flux Permanent Magnet (AFPM) machines when the pole-shift method is employed for cogging torque suppression, this paper proposes a novel Elliptical-Cut Rotating Compensated Halbach Pole Axial Flux Permanent Magnet (EC-RCHP AFPM) machine. The proposed machine suppresses cogging torque via elliptically cut rotating poles and compensates for the induced torque loss by introducing dedicated compensating Halbach auxiliary poles. First, the rotor topology of the proposed machine is presented, and an equivalent surface current model is established to elucidate its operating mechanism. Second, sensitivity analysis and response surface methodology are adopted to investigate the correlation between design parameters and performance responses, and the optimal parameter combination is obtained under given constraints. Finally, the electromagnetic characteristics of the proposed machine are comprehensively analyzed through three-dimensional finite element analysis (3D-FEA). The results demonstrate that compared with the conventional machine, the EC-RCHP AFPM machine reduces cogging torque by 54.9%, increases average output torque by 1.8%, and lowers torque ripple to 6.12%, effectively resolving the fundamental trade-off between cogging torque suppression and torque output retention.

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Prof. Zhongan Yu

Mr. Long Chen

Dr. Zihao Deng

Dr. Feng Zhang

Mr. Fangrong Wang

Dr. Zhiguo Zhu