Control apparatus for vibration driven motor

摘要

Disclosed is a unit for attenuating frequency components generated in a sideband of a frequency of an AC voltage applied to an electro-mechanical energy conversion element. This attenuation is achieved by modulation performed in a speed control apparatus for a vibration driven motor. The control apparatus includes a filter for cutting frequency components of a smaller frequency difference (fd) or more of an absolute value of a frequency difference between a natural frequency of an n-th order vibration and a natural frequency of an (n-1)th- or (n+1)th-order. A filter output is input to a modulator in a driving circuit, and noise of the vibration driven motor can be greatly reduced.