Characterisation and Modelling of Piezoceramic Actuator Hystereses

Abstract

Piezoelectric ceramics are often used as actuators in smart structures technology. In the vast majority of papers dealing with this topic only linear constitutive relations are used. However, the electric field‐strain relations of such actuators show hysteretic behaviour, which means that the piezoelectric coupling coefficient is not constant. In this study the hysteresis of a mechanically unconstrained actuator is obtained using the Michelson interferometry. The hysteretic behaviour is modelled by a Preisach model. Using these experimental data, for the modelling of an active structure with embedded piezoelectric actuators the actual coupling coefficient can then be determined with the help of the Preisach model. With this procedure the actuation strain of an embedded actuator, including the physical nonlinearities, can be calculated using the material characteristics obtained for an unconstrained actuator. For an experimental validation of the method outlined above, a Lead Zirconate Titanate (PZT) actuator is characterised experimentally and then glued to a cantilever beam. Then, the tip displacement of the actuated beam is determined experimentally and simulated numerically using the above method. The experimental and numerical results agree reasonably well if the shear lag due to the bonding layer between the actuator and the structure is taken into consideration. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Experimental and Numerical Investigation of Nonlinear Piezoelectric Effects Including Minor Hystereses

“…The Michelson interferometry is used to measure the strain of the mechanically unconstrained ceramic due to the application of a driving voltage [2,5]. After characterisation the laminar piezoceramic is glued with an electroconductive 2-component epoxy to a spring band steel beam.…”

“…The disadvantage of this model is the multilinear representation of hysteresis. In [2] a hysteretic operator, the Preisach operator, is used to model minor hysteresis loops even for the mechanically constrained ceramic. The Preisach model in [3] is able to reproduce the minor loops of a free actuator, but there is still a lack considering ferroelastic effects appearing in an active structure.…”