Hysteresis Characterization in Piezoceramic Stack Actuators and Its Influence on Vibration and Noise Reduction in Helicopters Using Actively Controlled Flaps

In this study, a characterization of hysteresis in a piezoceramic stack actuator similar to those employed in an actively controlled flap (ACF) system is performed to assess the effects of hysteresis on system performance. The effect of unmodeled actuation hysteresis may significantly reduce vibration and noise reduction capabilities. A hysteresis model based on the classical Preisach model has been developed from experimental data. The model displays good agreement with experimental data for input frequencies typical of those used for vibration and noise reduction in full-scale rotors. The hysteresis model has been incorporated into the Active Vibration and Noise Reduction (AVINOR) code, developed at the University of Michigan, so as to evaluate the effect of piezoceramic actuator hysteresis on vibration and noise reduction. The incorporation of hysteresis does not produce a significant performance degradation of the ACF system for vibration reduction at blade-vortex interaction (BVI) and dynamic stall conditions. For BVI noise reduction, hysteresis produces significant differences in flap deflection time histories, demonstrating the importance of hysteresis modeling. However, the overall noise reduction performance of the ACF system is not significantly affected.