amortisseur winding

Wiktionary

1. n. A squirrel cage winding placed near the surface of the pole faces of a synchronous motor. Its main purpose is to dampen any speed fluctuations that may occur as a result of sudden load changes. It is also used to accelerate the motor during starting. As the rotating field moves past the winding it induces currents in the winding which produce torque and accelerate the motor.