Increasing the Operating Speed of a Consequent Pole Axial Gap Motor for Higher Output Power Density

摘要

In this study, we examine how to increase the operating speed of a consequent pole axial gap motor to achieve higher output density. Our research group has been developing a consequent pole axial gap motor with field windings as the traction motor for electric vehicles. A smaller and lighter traction motor is required for better fuel economy and layout of such vehicles, and it is profitable to manufacture a smaller motor with an increased operating speed. To achieve high-speed operation, it is necessary to suppress the line-to-line voltage, and to that end, we examine the slot/pole combination. Moreover, because the rotor outer diameter of an axial gap motor is larger than that of a radial gap motor, the rotor strength should also be considered. We study the use of non-magnetic high-tensile-strength steel for the component that supports the rotor. We present the motor design and the results of spin burst tests, and we confirm that the motor can operate at the target maximum speed and output power density.