Electromechanical interaction in a synchronous reluctance machine

Electromagnetic forces on a whirling rotor of a synchronous reluctance machine are studied using time-discretized 2D finite-element analysis. The whirling motion generates eccentricity harmonics in the air-gap field. These harmonics may further induce circulating currents in the windings of the machine. The dynamics of the induced currents is coupled with the dynamics of the rotor, especially, when the machine is operated close to its first bending critical speed. In a synchronous reluctance machine, there is no rotor winding but the circulating currents may flow in the parallel branches of the stator. This electromechanical interaction and its effects on the rotordynamic stability are studied.