Abstract
A novel 5-degrees of freedom (DOF) controlled magnetically levitated motor has been developed for paediatric ventricular assist device (VAD). The motor has a top stator, a bottom stator and a levitated rotor which is sandwiched by the both stators. A double self-bearing motor mechanism enhances a higher rotating torque production and realizes a 5-DOF active control of rotor postures. This paper investigated a magnetic suspension ability and rotation ability of two motors which are made of soft magnetic iron and powder magnetic core. The developed motor is 28 mm in diameter and 41 mm in height. The maximum energy efficiency is sufficiently increased from 46 % to 72 % by using the powder magnetic core motor, although the magnetic axial attractive forces are only slightly reduced by 10 % of the soft magnetic iron motor. The powder magnetic core motor has sufficient performance as an actuator of the paediatric VAD.
