Thermal design method and experimental research of magnetically suspended reaction flywheel

As a novel type of actuator of the spacecraft for attitude control, the magnetically suspended reaction flywheel operates in a vacuum with its rotor suspended, making it difficult for its inner heat to dissipate, which results in the need for temperature calculation and thermal design. In this paper, a method composed of a finite element method and a thermal network is proposed as follows: first, the finite element model calculates the temperature distribution, and then the thermal network analyzes the factors that affect the higher temperatures and provides methods for optimization to enable the method to work precisely and quickly. The method is applied to the thermal optimization of a certain magnetically suspended flywheel, and is able to decrease its maximal temperature from 121.6 °C to 52.7 °C. Experiments are carried out on flywheels with and without optimization, and the results prove the feasibility of the analysis. This study may serve as a basis for the structural and thermal design of a magnetically suspended flywheel system.