Design Optimization of a Novel Heteropolar Radial Hybrid Magnetic Bearing Using Magnetic Circuit Model

In this paper, one novel heteropolar radial hybrid magnetic bearing (HRHMB) with low-power loss is proposed for flywheel energy storage system. First, its structure and equivalent magnetic circuit (EMC) are introduced in detail. Then, some main design parameters are analyzed based on EMC, including air-gap bias flux density, magnetic pole area, permanent magnet (PM) dimensions, and control current. Furthermore, to improve the performances of the novel HRHMB, the optimizations are implemented both on its structure and some key size parameters, such as the second air-gap length, PM height, and width. Finally, the optimal scheme is verified by the 3-D finite-element analysis, which indicates the maximum control current can be reduced to only 40% that of initial design by the optimizations.