Performance Assessment of Coreless Permanent Magnet Synchronous Motors for Position holding Mechanism for Spacecraft Applications

摘要

This paper investigates the performances of 3-phase and 2-phase coreless Permanent Magnet Synchronous Motor (PMSM) for a position holding mechanism used in spacecraft. Configuration study of coreless PMSM was carried out to select the stator-rotor configuration and it is found that enclosed rotor has higher torque density than outside rotor configuration. Detailed design and analysis of 3-phase and 2-phase PMSM were carried out. Rotor is designed to generate sinusoidal flux in the airgap. Three different winding pattern for 3-phase PMSM were studied and the Sine distributed winding generates higher torque. 3-phase and 2-phase PMSM are realized and characterized. Ripple free torque is achieved in both motors. 3-Phase PMSM has better performance indices than 2-Phase PMSM. Torque density of 2-phase PMSM is 33% lesser than 3-phase PMSM. If torque density is the driving factor, 3-phase PMSM is the ideal choice. With resolver as the angle sensor, for position holding application, 2-phase PMSM is a better option.