1. The Motor Selection Liping Zheng University of Central Florida

2. Motor Specifications  Must have high reliability.  Efficiency is most important, volume and weight are also important. Speed50Krpm Power output100KW Efficiency>94%

3. Alternative Motor Types (I)  Permanent Magnet Synchronous Motor (PMSM)  Has high power density and high efficiency.  Can obtain high efficiency due to no copper loss associated with motor excitation.  Requires rotor position measurement for high efficiency operation.  Brushless DC Motor (BLDC)  Also has high power density and no copper loss associated with motor excitation.  Has high iron loss at high speed comparing with PMSM.

4. Alternative Motor Types (II)  Wound-Field Synchronous Motor  High power application. Not good for speed higher than 25krpm because of rotating windings, slip rings, and brushes.  Switched Reluctance Motor (SRM)  Provides fault tolerance. Has high losses and low efficiency at high speed.  Induction Motor (IM)  Low cost alternative to PMSM. Larger in size than PM motor but close to PMSM in efficiency.  Asynchronous motor, need speed control.

5. Motors available  Turbocor  PMSM with magnetic bearing  140hp (104kW) @ 48Krpm  Electrodynamics associates inc.  Induction motor. Under development.  200kw @ 62Krpm (160kw @ 50Krpm)  Efficiency >95%.