2023 年 31 巻 2 号 p. 257-263
A pediatric ventricular assist device (VAD) using an ultra-compact self-bearing motor, in which a 4-pole levitated impeller is magnetically supported and rotated by two identical 6-slot motor stators has been developed. The outer diameter and height of the motor are 22 mm and 35 mm, respectively. The previously developed motor uses electromagnets that integrate all the windings for magnetic suspension and rotation control. Each winding requires its own power amplifier, which makes the drive system complicated. This paper investigated to reduce the number of wires and the total number of power amplifiers by dividing the integrated winding into two insulated three-phase windings. A maglev VAD prototype with the separated windings was driven in a closed-loop circulation circuit, and indicated non-contact magnetic suspension at the operating condition of the pediatric VAD, although increased total energy input due to the increase in control current according to the reduction in the number of windings was clarified.