Position Controller for Piezoelectric Actuator
This paper presents a computer-based tracking control approach for a piezoelectric actuator based on incorporating a feedforward loop with a PID feedback controller. The purpose of this paper is to improve the hysteresis characteristics of a stack type piezoelectric actuator using the hysteresis nonlinearity compensator. The system proposed in this study prints by spraying the molten metal, and consists of a nozzle, heating furnace, operating actuator, and an XYZ 3-axis stage. As an operating system, the piezoelectric(PZT) method has very valuable uses. The PZT actuator, however, has a hysteresis nonlinearity due to the ferroelectric characteristics of the PZT element. This causes problems in the system position control characteristics and deteriorates the performance of the system. This study proposed a inverse hysteresis model, a mathematic modeling method that can express the geometric relationship between voltage and displacement, in order to reduce the hysteresis of the PZT actuator. In addition, system identification and PID control methods were examined. Also, it was confirmed that the proposed control strategy gives good tracking performance.
Soon-Bok Lee and Yun-Jae Kim
S. N. Yun et al., "Position Controller for Piezoelectric Actuator", Key Engineering Materials, Vols. 326-328, pp. 1399-1402, 2006