Journal: IEEE Transactions on Energy Conversion
Authors: Jae-Woo Jung, Kyung-Tae Jung, Byeong-Hwa Lee, Jung-Pyo Hong
DOI: 10.1109/TEC.2019.2897575
In order to improve the torque density of the magnetic flux concentrated permanent magnet synchronous motor utilizing a ferrite permanent magnet, it is important to reduce the leakage magnetic flux flowing through the rotor core. For satisfying the robustness of the rotating body and improving the torque density, we propose a structure in which two types of cores with different shapes are cross laminated. The proposed rotor structure consists of a core with a bridge that is necessary to maintain the rigidity of the rotor assembly, and a rotor assembly by cross laminating the segment-type rotor cores necessary for minimizing the leakage flux as well as improving the torque density. The complex three-dimensional (3-D) magnetic circuit of the cross-laminated rotor assembly has been modeled as a two-dimensional (2-D) model on the mathematical basis of an equivalent magnetic circuit. Using the equivalent 2-D model, the design of the cross-laminated rotor shape and the electromagnetic characteristics were examined comprehensively. At the same time, mechanical stresses due to centrifugal force and torque transmission between rotor core and shaft were examined. Finally, after the prototype was fabricated, the analysis and design methods were verified through no-load and load tests.