High Power Electrostatic Motor Using Skewed Electrodes

This paper describes a new type of high-power electrostatic motor based on skewed electrodes. The authors have developed several types of high-power electrostatic motors. Among them, Dual Excitation Multiphase Electrostatic Drive (DEMED) has the best performance in terms of power and its power/weight ratio is almost the same as those of the most advanced conventional electromagnetic motors. However, DEMED has large ripple of force and it leads to some defects such as low controllability, much noises and vibrations. To overcome those defects, the authors have proposed to apply skew technique to DEMED and have analyzed the effects of skewing electrodes. The analytical work have shown that the approptiate skewing can suppress the ripple of force considerably. In this paper, further analyses on the shape of electrodes are presented and a new type of motor depending on the analyses is fabricated and experimentd. Using the new DEMED with skewed electrodes, that is called V-DEMED, motion of the slider becomes much smoother, noises and vibrations become much smaller, and efficiency improves, without a lowering of thrust force.