A Comprehensive Study on Transverse Flux Motor for Direct Drive Low-Speed Spacecraft Applications

Transverse flux motor (TFM) has been proven to be the ideal choice for high-torque direct drive applications, thanks to its higher specific torque density than the conventional radial flux machine. This article investigates the suitability of using TFM as the drive motor for precise position control based spacecraft applications, where mass and power reduction are the everlasting demands. Comparative configuration studies have been carried out to find the suitable type of permanent magnet motor for this application. Surface mounted TFM (SM-TFM) outweighs its competitors with lower power requirement and higher average torque, but with increased ripple content. Parametric studies of SM-TFM have been carried out to arrive at an optimal design of variables. To further increase the torque density, flux concentrated (FC) configurations of TFM have been analyzed. Average electromagnetic torque of FC and claw pole type TFM is higher than SM-TFM, with corresponding increase in the cogging torque. Electromagnetic simulation is carried out using Maxwell 3-D simulation software. Two variants of SM-TFMs are realized and the design is evaluated. Effect of Number of poles, material annealing, and strength of permanent magnet on the developed torque of SM-TFM are experimentally validated in the realized motor.