Precision tracking control of piezoelectric actuator using a hammerstein-based dynamic hysteresis model

Piezoelectric actuator has been frequently utilized in the micromanipulation control. However, the rate-dependent hysteresis properties in the actuator affect severely the high precision tracking control. In this study, a Hammerstein-based model with Bouc-Wen hysteresis nonlinearity is proposed to describe the dynamic characteristics of rate-dependent hysteresis in a piezoelectric actuator. The Bouc-Wen model parameters and the linear dynamic block parameters are identified respectively by particle swarm optimization algorithm and recursive least squares algorithm. Based on the proposed dynamic model, a new control scheme with a hysteresis compensator is developed for precise tracking control of the actuator. To verify the effectiveness of the proposed rate-dependent modeling and control scheme in practical application, an experiment of a piezoelectric actuator is implemented by dSPACE with the frequency excitation range of 1-100 Hz. The experimental results show that the relative error of tracking control is less than 8% for both single frequencies and compound frequencies in the given frequency range.