Hysteresis compensation of piezoelectric actuators under dynamic load condition

The piezoelectric actuator (PEA) accuracy is limited due to hysteresis nonlinearity as well as mechanical loading effect. Investigation of the fundamental properties of the piezoceramics depicts that the external mechanical loads cause inclination in hysteresis loop can deteriorate tracking performance furthermore. Other limiting problem is the rate dependency of hysteresis nonlinearity in PEA. Herein a new controller scheme to compensate mentioned limiting factors in PEA is presented. In this study an adaptive inverse control method based on modified Prandtle-Ishlinskii operator is proposed. It compensates both the rate dependant hysteresis nonlinearity and the mechanical loading effect in PEA. The controller structure has a simple design and can be quickly identified. The control system is capable to achieve suitable tracking control only by measuring the applied external load and rate of control input. Therefore it is convenient to use and can be quickly applied to the practical PEA applications. To verify the efficiency of the proposed method, we have conducted simulation by using the PEA system model as the unknown piezo actuator (PEA) dynamic.