A Novel Magnetic Multiple Spur Gear for High Speed Motor System

Magnetic gears achieve the system with maintenance-free, low noise and low vibration characteristics by contact-less power transformation. However, conventional flux modulation type magnetic gears are not suitable system for high speed motors because the mechanical strength is weak due to permanent magnets of the high speed rotor. Adding that, the gear efficiency much decreases by increased the magnet eddy current loss and core loss in high speed region. To overcome these problems of the flux modulation type magnetic gears in high speed region, this paper presents a novel magnetic gear which based on the direct flux transmission method to achieve the high efficiency and to make downsizing the system. It is shown that the proposed magnetic gear of the direct flux transmission type realizes the high performances such as high torque density, high efficiency, and downsizing of gear.