Development of Hybrid Type Self-Bearing Motor without Extra Bias Permanet Magnets

A segmented permanent magnet rotor is proposed to generate sinusoidal flux density for hybrid type self-bearing motor. It also provides bias flux for the hybrid type magnetic bearing without extra bias permanent magnet. Hence the construction of self-bearing motor is simpler and reliable. First, the concept of the proposed hybrid type self-bearing motor is introduced. Then the radial force is analyzed to be proportional to the average air gap flux density, even though the air gap flux includes some opposite pole parts. Finally, the experimental setup is made to confirm the capability of the proposed motor. It can run up to 12,000 [rpm] and record 0.15 N.m/A torque and 9.8 N/A radial levitation force constants. The levitation is very stable. The motor has high performance for practical application.