Feedback/feedforward control of hysteresis-compensated piezoactuators for highspeed scanning applications

This paper presents a control scheme for piezoelectric actuators (PEAs) in high-speed triangular trajectory scanning applications. Nonlinear hysteresis is compensated using a Maxwell resistive capacitor model. Based on the frequency response of the identified linear model, the feedforward compensation is proposed. This feedforward strategy is then combined with a proportional plus integral (PI) feedback controller for high-speed triangular trajectory tracking using piezoelectric actuator. Fast and precise tracking results are demonstrated through experiments. Moreover, it is found that the feedback loop does not always improve the tracking accuracy. When the input frequency exceeds a certain value, feedforward control only will result in better control performance.