A New Approach of Finding Transfer Function of Piezoelectric Actuator Using Finite Element Modelling

The piezoelectric element can be used both as actuator and sensor. The control of the piezo element system requires knowledge of transfer functions between the input and the output of the system. The transfer function is complicated to be determined using an analytical approach, especially for a thin structure with embedded actuators and sensors. The goal of this paper is to present a new approach using a finite element formulation for the piezoelectric element as an aiding tool for an analytical approach to estimate the system transfer function. A 3D finite-element model is developed with piezoelectric patches, which are surface bonded on a thin quadrilateral plate and supported with spring damper elements. The results show that the behaviour of the piezoelectric element for various electric excitation and motor vibration depends on the different frequency range. The mode shapes and natural frequencies at specific frequency spectrum are also presented. It can be concluded that the finite element modelling can be used as a new tool for scientific investigation of this material in various form.