Torque Improvement of a Dual Rotor Coreless Axial Flux-Switching Generator for High Speed Wind Turbine

Document Type : Research Paper

Authors

1 - Department of Electrical Engineering University of Science and Technology of Mazandaran Behshahr, Iran.

2 Elctrical and Computer Engineering Department Babol Noshirvani University of Technology Babol, Iran.

Abstract

Coreless axial flux permanent magnet (PM) machines (AFPM) have attracted significant interest over the last decades as an ideal candidate for a wide range of applications. This is generally due to their advantages, such as the high torque density, high power density, and the light weight. This paper investigates the performance of a coreless axial flux-switching generator (AFSMG) with improved torque characteristics. The inherent feature of the axial flux-switching machines is the high cogging torque. Hence the main advantage and the novelty of this research is addressing a suitable key for its torque characteristics challenges. In this regard, a comprehensive study is done on rotor tooth shape. First, the geometry and the shape of the rotor tooth are optimized, and then the skewing technique is applied to minimize the cogging torque and improve the total harmonic distortion. Finally, the cogging torque and the THD are calculated in the primary design and the optimal design. The Taguchi method is utilized to improve the primary model. A comparative analysis of the primary and optimized model is carried out, which indicates the better performance of the optimized design. Furthermore, the 3D finite element method is applied to verify the results of the presented model.

Keywords

Main Subjects


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