Amortisseur winding In most synchronous motors the amortisseur winding is used to accelerate the synchronous motor close to synchronous speed. The amortisseur winding is simply a squirrel-cage winding placed near the surface of the pole faces. 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. It works exactly the same way as a squirrel-cage motor.