Patent ID: 6525446
Filing Date: 2003-02-25
Classification: H02K,H02N

Abstract:
A method of driving an electrostatic actuator which has a stator driving electrodes in plural phases and a traveler relatively moved along the stator by application of a driving voltage to the driving electrodes, where the driving voltage applied to the driving electrodes is decided according to a voltage function employing as an argument a relative movement position of the traveler on the stator, andwherein the voltage function is obtained by a procedure comprising steps of determining an electrostatic capacity between the traveler and the driving electrode, obtaining a first derivative and a second derivative of the electrostatic capacity with respect to the position of the traveler, and setting driving voltages to satisfy the relations: 0=12&it;&Sum;k=1n&it;&dd;Ck&dd;x&it;Vk20>&Sum;k=1n&it;&dd;2&it;Ck&dd;x2&it;Vk2where Vk is a driving voltage of the k-th phase, x is the position of the traveler relative to the stator, n is a number of phases of the driving electrodes, and Ck is an electrostatic capacity between the driving electrode of the k-th phase and the traveler.