2-D Electromagnetic Analysis Coupled With 3-D Thermal Analysis of a Dual-PM Excited Flux-Switching Generator With Overhang Structure for Direct Drive Wind Turbines

Abstract

This study introduces a new outer-rotor dual-permanent magnet (PM) excited flux-switching generator with an overhang structure for direct-drive wind turbine applications. The proposed generator incorporates flux barriers and ferrite PMs in the stator while utilising neodymium PMs in the rotor segments. Contrary to ferrite PMs, neodymium PMs are prone to demagnetisation in high-temperature conditions. Given that the operating temperature of the stator is nearly double that of the rotor in this study, ferrite PMs are strategically positioned in the stator to mitigate this issue. The main goal of this paper is to provide a fast and accurate method to study the electromagnetic-thermal performance of the generator. Hence, a two-dimensional finite element analysis (2-D FEA) electromagnetic analysis is coupled with a 3-D FEA thermal analysis. Moreover, a precise thermal circuit of each generator's element is displayed. Finally, the accuracy of the method is confirmed through a comparison of the simulation results with experimental data, indicating a small margin of error.