Research On Soft Switching Technology Of High Frequency Switching Power Supply

Now the rapid development of power electronics,high-frequency switching power supply applications in various fields more and more attention has been widely used.But at the same time,the requirements of power supply equipment are getting higher and higher,mainly reflected in: power density,withstand temperature,efficiency and so on.Soft-switching technology can greatly improve the efficiency of the power supply device,High-frequency switching power supply through the soft-switching technology can make the main power switch when the voltage reaches zero or turn off when the current reaches zero,significantly reducing the breaking loss,making the efficiency is improved,while reducing the heat dissipation and reduce the impact of electromagnetic interference.Usually soft-switching circuit using full-bridge phase-shift converter,such a converter topology has a simple,easy to control,reducing switch voltage stress characteristics.From the current point of view,the traditional power switch made of Si material can not meet the switching power supply high-frequency,high efficiency needs,Which requires extensive attention and performance superior SiC material to be replaced.This article uses a new type of high-frequency SiC material composed of the main power devices,starting from the phase-shifted full-bridge converter,each working mode of the soft-switching is analyzed one by one.A new type of driving circuit suitable for multi-transistor parallel connection is designed for SiC MOSFET switch.Through MATLAB simulation software to verify that when in high-power high-necked switching power supply parallel environment,the system can still be stable operation,the final assembly of a 30 kW high-frequency switching power supply prototype,mainly for the forearm to achieve the soft-switching technology was verified.