Compensation of Hysteresis Nonlinearity for the Piezoelectric Actuators

These Adaptive inverse compensation is adopted to eliminate the hysteresis nonlinearity of piezo-actuator in active control system. The adaptive control law based on grads method is obtained with Prandtl-Ishlinskii model. It is proved that when Prandtl-Ishlinskii model is used, results of compensation have no contact with slopes under the assumption that backlash model has a symmetry structure and backlashes as well as slopes are all proportional with each other. As only proportion of reference input and output is related with slopes, the estimated parameters are reduced to only one. The results of simulation indicated that compensation effect of adaptive inverse control to hysteresis nonlinearity was much better when signal frequency was low.