An electrostatic micromotor based on electrets

The authors report a novel electret-based miniature electrostatic motor with an electret film as the stator and a metal electrode as the rotor. A particular commutator is used to transform the polarity of the metal electrode. When the size of the electret-based electrostatic motor (EEM) is 42 × 44 × 15 mm³, the maximum power consumption is only 5.4 mW. The rotation speed of the EEM increases with the increase of the supply voltage, and the maximum rotation speed can reach up to 2864 rpm. Powered by two nickel-hydride batteries with a rated capacity of 1700 mAh, the EEM can drive a fan with a diameter of 40 mm to rotate continuously for 18 h. The EEM has the characteristics of low power consumption and convenient fabrication. Experimental results show that the EEM demonstrates high reliability and has potential applications in micro-electromechanical systems.