Performance Calculation of a Dual Stator Solid Rotor Axial Flux Induction Motor Using the Multi-Slice and Multi-Layer Method

This paper proposes a novel dual stator solid rotor axial flux induction motor (DSSRAFIM) for a low-cost flywheel energy storage system. To simplify the analysis of its 3-D electromagnetic field distribution (EFD), a novel multi-slice and multi-layer method is applied. By this analytical method, DSSRAFIM is equivalent to a finite set of double primary steel secondary linear induction motors (DSSLIMs), and the steel secondary in each DSSLIM is divided into a finite set of layers with equal height. The EFD in each layer is obtained by solving Maxwell's equations. The EFD calculated by this novel analytical method is in good agreement with those analyzed by the finite-element method (FEM). Compared with the FEM, this novel analytical method is time saving, resulting in that it is suitable for the optimized design. According to the EFD in DSSRAFIM, an equivalent circuit model (ECM) of DSSRAFIM is derived, which is an effective approach to predict the performance. The electromagnetic torque, efficiency, and power factor of a 5 kW, 7100 r/min prototype calculated by the ECM, FEM, and experimental test verify the validity of the ECM.