Twice-Line-Frequency Pulsating Torques in Shaded-Pole Motors

This paper describes a theoretical and experimental investigation into the design parameters which influence the magnitude of the twice-line-frequency pulsating torques in shaded-pole motors. Linear analysis is shown to be capable of producing calculated results which agree well with the experimental results over the normal range of motor operation. It is shown that pulsating torques are most sensitive to changes in stator-side parameters, and that by careful design they can be considerably attenuated.