An Analysis on Performance Improvement of Electrostatic Motor by Skewing Electrodes

Abstract

The authors have developed high-power electrostatic motor called Dual Excitation Multiphase Electrostatic Drive (DEMED). This motor possesses 230W/kg of power/weight ratio and this is much higher than those of conventional electromagnetic motors. However, the motor has some problems with the quality of its output, such as low positioning resolution or much viblations, since its force generation is rippled. In case of electromagnetic motors, torque or force ripple is removed by skewing slots of their armatures. Similaly, the force ripple of DEMED is expected to be removed by skewing their electrodes, instead of slots. In this paper, the effect of skewing electrodes of DEMED is analyzed, and the analytical results show that appropriate skewing will suppress the ripple considerably and will raise effective force of DEMED.