Design Of Distributed Power Supply System Based On Soft-switching Technology

With the development of Power Electronics,dps system has convertered from linear power supplies into high frequency switching power supply,which makes it more smaller and efficiency,and help realize its Intelligent and Modular. Although volume of transformer and filter inductor is reduced by higher frequency, the high working frequency also bring in Harmonic problem at the same time, all of these finally give us a lower efficiency and power factor.In order to reduce switching loss and increase power factor, this paper designs a DPS system based on PFC,soft-switching and current sharing technology. First introduce the progress of PFC design in detail, and then introduces the basic principles and implementation method of soft-switch technology. Further more, in order to meet the needs of users, system combines with current sharing technology to increase redundancy and security.The input of the first grade is 220±15%V, output is 48V (which is also the input voltage of the second grade). The first grade mainly finishes the design of the PFC circuit, peripheral circuits of control chip UC3875, high frequency transformer, current sharing and control circuit, phase-shifted full-bridge converter and protection circuit.There are also overload and overtemperature protection circuits to enhance the reliability; The second grade includes four power modules, including 15V/10A half bridge module,36V/3A forward module,5V/2A and 24V/3A flyback modules, and they also have overload protection circuits.At last, with the help of PSPICE simulation software, the progress of the soft-switching is simulated in computer, and voltage waves of the primary side of the high frequency transformer are observed. And these two modges are confirmed to be feasible; Finally, complete the forward module and flyback modules'installation and debugging, give the test results,to confirm the feasibility of this modules.