Double Stator Axial Gap Type Ultra-Compact 5-DOF Controlled Self-Bearing Motor for Rotary Pediatric Ventricular Assist Device

Ventricular assist devices (VADs) which employ a maglev motor have significant advantages of high mechanical durability and better blood compatibility by eliminating mechanical contact for impeller suspension. In the last decade, research interest in maglev VADs for small pediatric patients is highly increased. However, drastic miniaturization of maglev motors has technical difficulties in deterioration of suspension stability and energy efficiency. Our group has developed an ultra-compact axial gap double stator self-bearing motor utilizing 5-degrees of freedom control for pediatric VADs to overcome the above technical drawbacks. In this article, feasibility of the proposed self-bearing concept for stable impeller suspension was verified, as well as enhancement of energy efficiency of the developed self-bearing motor was investigated by modifying motor core material and winding design. In pump operation with the modified motor, noncontact impeller suspension with energy input of 3.2–5.2 W over a range of pediatric circulatory support (4000–5000 r/mim) was demonstrated.