Narrow-control-bandwidth Operation Of Piezoelectric-transformer Converter

The piezoelectric transformer (PT) is an electro-mechanical device that transfers electrical energy through the mechanical vibration. It has the following features: high voltage-gain, high power density, compact size, and no electromagnetic noise. Since it was proposed in the 1950s, PT is employed effective to lower the profile of power converter applying in the field of electronic power. And now PT as a power device of power converters has become an important research area.This paper is mainly research the narrow-band control and the current control of the PT converter, complete the following works 1) The narrow-control-bandwidth operation of PT converter. The paper introduces the input matching network (IMN), theoretically proves the fuction of the IMN and gives out the design method of the IMN. 2) The small signal of the current control loop. The paper dicusses some kinds of different current control methods, and then through small signal analyse of the current loops gives out the small signal models of the PWM and PFM control of the current loop and the interrelated simulaton results. 3) The drive signal problem and the open loop experiment. The paper builds the electric model of the drive circuit, and based on the model and some experiments, solves the drive signal problem. Then, the paper completes the open loop experiments of the current control.At the end, the paper gives out some conclusions and unsolved problems for discussion, and hopes that the results could be helpful in designing the resonant converter.Besides, the writer of this paper also accomplishes the small signal model of current-programable-control of a nonideal transformer dual switch forward converter. You can see the detail in appendix A.