| With the continuous development of switching power supply(SPS)technology,high-power SPS plays an increasingly important position on all walks of life occupy.At present,high-power SPS is moving in high-frequency,high-power,high-efficiency,high-reliability and digital direction.Low-voltage high-power SPS due to the characteristics of low-voltage high-current output,has been applied in many areas of heavy industry.With the country to build energy-saving,environment-friendly society’s request,how to improve the efficiency of high-power SPS is the common theme of all industry personnel.Therefore,there has a great significance on research related technologies of it.This paper will be low-voltage high-power DC power supply as the object,to study how to improve its efficiency and achieve digital control.Adopted a digital control strategy combining soft-switching and synchronous rectification(SR),The whole digital control system is composed of DSP + CPLD.This paper builds a 12V/1000 A hardware experimental platform,the whole system including the main power circuit,control circuit and auxiliary power.Small-signal model of the main circuit is proposed by using the state space averaging method.By using the theory of zero-pole compensation of the automatic control theory,designing a reasonable closed-loop controller.In order to verify the correctness of the proposed control strategy,this paper uses MATLAB to build the simulation platform.The simulation results show that the proposed control strategy can realize the full-soft-switching of the full-bridge circuit,and the correctness of SR control strategy is verified.Finally,through experiments of the system,verify the digital controller waveform,drive circuit waveform and auxiliary power waveform correctness. |
