Longitudinal and lateral vibrations of a planar piezoceramic transformer

Recently, the author has investigated the characteristics of Rosen-type piezotransformer with accounting the difference in elastic compliances of input and output sections. The refined formula has been derived for a transform ratio. It was established that a transform ratio is inversely proportional to a square frequency. This fact explains why an operation of the planar transformers at higher modes of vibrations is not effective. The longitudinal mechanical stresses in excite and generate sections of the transformer are axisymmetric in respect to the separating line that is in good matching with the experimental data. In this paper, the previous authors results are used for analyse of the modes of vibrations, frequency behaviour of the transform ratio and input admittance of transverse-longitudinal transformer. The spectrum of vibrations of the piezotransformer compares with that of rectangular piezoelectrtic plate. It is shown that piezoplate has more rigid spectrum than piezotransformer. The coupling between lateral and longitudinal vibrations in piezoplate and piezotransformer is similar.