An electric motor that uses permanent magnets does not […]
An electric motor that uses permanent magnets does not have field windings that serve as electromagnets on the stator frame. Instead, the permanent magnets on the stator frame provide the magnetic fields that interact with the rotor field to produce torque. This eliminates the need to power the stator, thereby reducing electrical energy consumption.
Electric motors, with or without the use of permanent magnets, produce rotation from a repeated sequence of attraction followed by repulsion, which requires reversing polarity. Many attempts have been made to construct a motor using only permanent magnets to generate the magnetic fields for both the stator and the rotor, but they did not succeed.
Such a motor would be powered entirely by the intrinsic magnetic fields generated by permanent magnets. The discovery presented here allows permanent magnets to attract and repel in sequence, producing continued motion like an electric motor and without reversing polarity or the use of an external source of energy.
Most of us have handled permanent magnets and experienced the attractive and repulsive forces that occur between them. It is easy to imagine having the magnets do work for us. For example, the attractive force between two sufficiently strong permanent magnets can move an object as the magnets pull themselves together. However, to have the magnets repeat this work, they must be pulled apart.
The amount of work or mechanical energy required to pull the magnets apart is similar to the amount of mechanical energy the magnets generated when they pulled themselves together. Accordingly, permanent magnets are unable to work continuously on their own without an external source of mechanical energy to repeatedly pull them apart.