Research On Switching Power Supply And Parallel Technology Based On Thephase-shifted Full-bridge Converter

With the development of power electronic technology and the improvement of the property of the power electronic devices, low voltage, high current and high frequency have become the development trend of switch power supply. And in order to meet the demand of high-power supply and stable and reliable work, The parallel current sharing technology of switching power supply has aroused widespread concern.In view of high power, high switch frequency requirements and combined with the soft switch converter technology, this paper has studied and designed switching power supply based on phase-shift full bridge ZVS DC/DC converter. Finally, establish a parallel switching power supply system combined with the commonly used parallel current sharing technology.This paper introduces the research status and development trend of switch power supply firstly, and then analyzes the soft switching converter and parallel current sharing technology. In the aspect of topology structure design of switching power supply, this paper analyzes the working principle and problems of the phase-shift full bridge ZVS DC/DC converter. And according to the analysis of the working process of ZVS converter, this paper, designs switch power supply general circuit structure and selects the parameters of the electronic device. Then, through the state space method to analyze the small signal model of the full bridge converter, and design the double closed loop control system based on PI control combined with the model. And under the Matlab/Simulink environment,analyses open loop and closed loop system modeling and simulation of designed switching power. Finally, discusses the method of parallel current sharing and builds the parallel system model of switching power and through the study of the output waveform to analyses the flow effect.