A new type of self-bearing motor that uses Lorentz-type forces to generate both bearing force and motoring torque has been developed. The motor stator is of slotless construction with four three-phase windings. The motor rotor is constructed of 16 surface mounted permanent magnets (PM’s). The main advantage of the design is that it eliminates the tradeoff between motoring torque and bearing force with PM thickness as found in previous designs. This paper presents the dynamic model for the self-bearing motor and illustrates how the model is integrated into the overall system model of the motor test rig. The dynamic model is validated against experimentally measured transfer functions with good agreement between the two.

Issue Section:
Gas Turbines: Structures and Dynamics
Keywords:
test facilities, electric motors, controllers, stators, rotors, modelling, dynamics, transfer functions
Topics:
Bearings, Engines, Motors, Transfer functions, Rotors, Magnetic bearings, Control equipment
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 by ASME
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