Test Device And Steady State Circuit Model For PT Power Converter Of Output Power 150W

The piezoelectric transformer (PT) is an electro-mechanical device that transfers electrical energy through the mechanical vibration. It has the features of high voltage-gain, high power density, compact size, and no electromagnetic noise. Since it was proposed 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 area.During the studying of the PT power converter, it is important to establish a steady state circuit model of the PT power converter. Although few good results of this issue have been reported; and almost no analytic methods having been developed. We put forward a steady state circuit model and design a test device for PT power converter of output power 150W though the theoretical analysis.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, and the design method of main circuit for PT power converter has been put forward. So a new control technology namely narrow-band control is proposed by investigating the electric characteristic and the working feature of PT.In chapterIII,according to fundamental wave analysis of power resonant converter, steady state circuit model of power resonant converter are given out. So that the steady state circuit model of PT power converter, which is fundamental for its small signal modeling, is deduced,In chapterIV, applying voltage control loop, a test device for PT power converter of output power 150W has been made up, and design program include IMN, voltage control loop, PFM and over- current protection.At the end of the paper, some conclusions and unsolved problem are given out. This work is greatly supported by National Nature Science Foundation of China (No.50477054).