Novel Heteropolar Hybrid Radial Magnetic Bearing with Dou-ble-Layer Stator for Flywheel Energy Storage System

In this paper, one novel heteropolar radial hybrid magnetic bearing (HRHMB) with double-layer stator is proposed for flywheel energy storage system (FESS). Firstly, its topology and working principle are introduced in details. Then, some main dimension parameters are optimized to improve its suspension performance based on the equivalent magnetic circuit (EMC) and three-dimension finite element analysis (3-D FEA). Finally, the comparison of main performance indexes between the proposed HRHMB and conventional one under the same constraints is made, such as displacement stiffness, current stiffness and iron loss. It indicates that the novel HRHMB has smaller displacement stiffness, larger current stiffness and lower rotor iron loss, which is more suitable for high-speed FESS.