Design of the Longitudinal Mode Piezoelectric Transformer

The purpose of the present paper is to establish a method of design for a longitudinal mode piezoelectric transformer (PT). This method is based on the electromechanical model of the PT, which is derived by the Rayleigh-Ritz assumed mode energy method and equivalent circuit method. The assumed mode energy method is used to model the distributed piezoceramic structure for estimating the parameters of the equivalent circuit model of the PT. Moreover, the equivalent circuit model is used to estimate the electrical characteristics of the PT. Such as voltage step-up ratio, output power and efficiency can be derived by the equivalent circuit model. Therefore, the performance of the PT can be predicted by the geometrical dimensions and material parameters. This method can be used to make a comparison between various kinds of the design of the longitudinal mode PT. The design principle of a longitudinal mode PT will be discussed based the proposed method.