Estimation of Magnetic Suspension Loss in a 30000 r/Min One-Axis Actively Positioned Single-Drive Bearingless Motor

This study compares the estimated magnetic suspension loss, the mechanical ball bearing loss, the input power, and efficiency in the proposed bearingless motor and a ball-bearing-supported motor. Bearingless motors have the advantage of enhanced efficiency owing to their operation without mechanical ball bearings. In the experiments, input power related to speeds from 1000 to 30 000 r/min of the ball-bearing-supported motor and the bearingless motor were measured. Mechanical loss of ball bearing was measured as well; then, magnetic suspension loss of the proposed bearingless motor can be estimated. In addition, the efficiencies of both motors are evaluated.