Pt And Pt Power Converter Modeling

The piezoelectric transformer (PT) is an electro-mechanical device that transfers electrical energy through a mechanical vibration. It features high voltage-gain, high power density, compact size, and no electromagnetic noise. Since it proposed by Rosen in the 1950s, quite a few applications have been developed. PT is employed effective to miniaturize and lower the profile of power converter applying in the field of electronic power. Therefore the correlative development of new technology of power converter has become an important search point.In the studying of the PT power converter, it is important to establish the equivalent circuit model of PT and the modeling of the PT power converter .A few good results of this issue have reported and some analytic methods have been developed.At the beginning of the thesis, the significance of this project is discussed and the aim of the work is also expatiated clearly.In chapter II, the fundamental knowledge of piezoelectric material as well as the operation principle and equivalent circuit model of PT are reviewed; the electric-performance of power converter and some problems are also given out.The design of main circuit and the modeling of PT are essential to the research work. In chapter III,a new control technology namely narrow-band control is proposed by investigating the electric characteristic and the working feature of PT. Applying the theory, several types of input matching network (IMN) and output matching network (OMN) have been studied and some experimental results have been given out to show the performance of these modules. Furthermore, to analyze PT's electronic characteristic on different working condition, we set up some types of equivalent circuit model of PT, the simulation results are well agree with the experiment results.ChapterIV summarized the theory and the method of small-signal analysis for resonant power converter, on this basis, a new simple approach of small-signal modeling for high-order resonate converter, equivalent circuit method, is put forward. Small signal model of PT power converter is developed in this chapter with verification of simulation and experiment.At end of the paper, detail design method and process of voltage control loop in PT power converter are given, simulation results are provided to verify the superiority.This work is greatly supported by National Nature Science Foundation of China.