Suppression of Eddy Current Loss in Rectangular Winding of High Power-Density IPMSM Using Concentrated Winding Stator for More Electric Aircraft 2019-01-1910
In order to respond to worldwide environmental problems such as global warming and demands for saving fuel cost of aircrafts from the aviation industry, researches on More Electric Aircraft (MEA) are actively conducted. Conventional hydraulic, pneumatic, and mechanical power sources from aero engines for flight actuators or auxiliary systems are replaced by electric motors in MEA.
Interior permanent magnet synchronous motors (IPMSMs) are widely used in various applications for high power density and high efficiency. It is considered that rectangular windings can greatly improve the slot factor, thereby making it possible to increase the power density of IPMSMs. Additionally, in the concentrated winding stator, the coil end can be made shorter than that of the distributed winding stator, which is possible to downsize the stator in the axial direction.
In this paper, a high power density concentrated winding IPMSMs which employs rectangular windings for MEA is simulated by 2D-FEA. However, this simulation result reveals that considerable amount of eddy current loss generated in the windings of the motor. Excessive eddy current loss in the windings increases loss density of the motor, and this makes it difficult to cool down the motor which is required for continuous operation. Therefore, teeth geometry is modified in order to reduce eddy current loss in the rectangular windings. Eventually, the proposed IPMSM achieves considerable reduction of the eddy current loss in the stator windings by optimizing teeth structure. Additionally, the proposed IPMSM indicates higher efficiency than conventional models, and it is confirmed that the proposed motor achieved all the requirement.