Dynamic reduction of unbalanced magnetic force and vibration in switched reluctance motor by the parallel paths in windings

The influence of winding method counteracting unbalance forces on the rotor vibration behavior is investigated in this paper. Unbalanced magnetic force caused by rotor eccentricity may degrade the performance of motor, increasing vibration, acoustic noise, excessive wear of bearing and degree of eccentricity. This paper proposed a method to reduce the unbalanced magnetic force and vibration by introducing parallel paths in windings. The motor was simulated by using 2D transient magnetic FE analysis coupled with external circuits. Serial connection and various parallel connections of windings were modeled in the external circuit. It was found from the simulation results that the currents could be balanced in parallel paths and unbalanced magnetic forces could be reduced. Experiment results also reveal that the acceleration of stator surface is minimum with the proposed method.