Thrust ripple measuring apparatus and method in linear motor

摘要

In a thrust ripple measuring apparatus for use in a linear motor, a slave linear motor as a subject to be measured is coupled with a master linear motor through a non-contact type stage mechanism. A processing unit is supplied with speed-induced-voltages detected by a voltage detector and a moving speed of the slave linear motor detected by a speed detector and calculates a per-phase induced voltage constant from the ratio of the speed-induced-voltage of each phase and the moving speed and further calculates a thrust constant and a thrust ripple from the calculated per-phase induced voltage constant.