Development of Lorentz Force Type Self-Bearing Motor using Halbach Magnet

Abstract

This paper proposes a new type of self-bearing motor which uses Lorentz force with Halbach magnet. It is expected to have a good dynamic response and high levitation capability. For realizing high magnetic flux airgap, Halbach magnet is used for the rotor. First, the fundamental principle is introduced how the motor produces rotating torque and radial levitation force. Next, Halbach magnet is introduced and the motor is designed. However, the control forces for x and y directions are quite different and the levitation is unable. For the stable levitation two sets of three phase coils are used. The levitated rotating test is carried out successfully. The top speed of 4 410 rpm and the maximum motor efficiency of 72% are recoded.