Thermal Analysis and Optimization of Homopolar Inductor Machine for Flywheel Pulsed Power Supply Applications

As a key component of flywheel pulsed power supply system to realize energy conversion, homopolar inductor machine (HIM) is considered as a strong competitor among all the electrical machines due to its merits of simple structure, robust rotor and rotor flywheel integration. However, in order to further improve the power density of the machine, it is required to work under high speed and high electromagnetic load., which will cause high loss density., high temperature rise., and bring the risk of fatal error. Addressing the issue., the several thermal optimization methods are applied and examined. First., the topology and operation principle of the HIM is explained. Then the finite element (FE) model and heat source model is obtained., and performance and loss distribution is calculated. Finally., a rotor pole slotting method and a novel cooling channel is proposed., and the temperature rise inside the HIM is examined using FE thermal analysis. The results show that the temperature of HIM can be effectively suppressed by the proposed method and cooling channel in this work.