Performance of driving method of piezoelectric actuator by using current pulse

Piezoelectric actuators have a potential for high displacement resolution. However, in the case of driving through a digital to analog converter, its resolution restricts the ratio of the deformable range to the resolution of the piezoelectric actuator. This study aims at the displacement control with the high resolution throughout the deformable range by driving with a series of current pulses. In this paper, a driving method with the intention of applying to the pulse density modulation control is proposed and the results of the displacement control of a stacked piezoelectric actuator are described. In the feed-forward control, the hysteresis in the drive by current pulse was much smaller than that by a linear amplifier because the driving pulse with a constant duration can be regarded as a charge pulse. In the feedback control, the displacement could follow the reference. Therefore, the driving performance was as well as that by a linear amplifier