Reconfigurable inductive to synchronous motor

摘要

A reconfigurable electric motor includes rotatable permanent magnets in a rotor, the magnets having a first position producing a weak magnetic field and a second position producing a strong magnetic field. The motor is reconfigurable from an asynchronous induction motor at startup into a synchronous motor for efficient operation. The motor includes a squirrel cage for induction motor operation at startup with the permanent magnets positioned to product the weak magnetic field to not interfere with the startup. When the motor reaches sufficient RPM, the permanent magnets rotate to produce a strong magnetic field for high efficiency synchronous operation. The permanent magnets are magnetically biased to come to rest in the weak magnetic field position and a centrifugal mechanism holds the magnets in the weak magnetic field position until sufficient RPM are reached for transition to synchronous operation.