Improvement of control method for piezoelectric actuator by combining induced charge feedback with inverse transfer function compensation

摘要

This paper deals with a displacement control method of a piezoelectric actuator (piezo). When voltage is applied to a piezo with conductive plates attached on both ends of the piezo, charges are induced on the conductive plates. This induced charge indicates the deformation of the piezo. The ratio of the displacement to the induced charge does not depend on the amplitude and the bias of the applied voltage. The hysteresis of the displacement to the induced charge is 2% though the hysteresis to the applied voltage is 14%. The induced charge has high response as the displacement. The displacement of the piezo can be controlled by the feedback of the induced charge as well as by a feedback of the displacement with other measuring instruments. This method can be used at a high driving frequency since the piezo is driven with a voltage source with a low output impedance in this method.