Repulsion Motor

A repulsion motor is a type of alternating current electric motor, classed among single-phase motors, that was formerly used as a traction motor for electric trains before being superseded by other designs. Its stator windings connect directly to the AC supply, while the rotor, fitted with a commutator and brushes, generates its own current through electromagnetic induction rather than a direct electrical connection. Rotation is controlled by the angle of the brushes relative to the stator field: when the brushes align with the field no torque develops, but as they are angled away from that alignment the induced rotor current creates an offset magnetic field whose repulsive interaction with the stator field drives rotation, reaching maximum torque at a 45-degree brush angle.