Design And Realization Of High Frequency Switching Power Supply Based On PFC

High frequency switching power supply is widely used in power plants and substations,which is the basis of power system control and protection.The power supply is for the control load,power load and accident lighting load.The traditional power supply adopts phase controlled rectifier,which has the disadvantages of large output voltage ripple,low power factor,serious harmonic pollution and large size.In this paper,switching power supply adopts Boost circuit and DC/DC converter in cascade mode.It can achieve high power factor and get better output voltage.Firstly,in this paper,the development of switching power supply and its present research situation are introduced.Comparing several traditional power factor correction circuits,DC/DC converter and analyzing their advantages and disadvantages.Then,we get a solution.The input stage adopts single-phase uncontrollable rectifier and Boost circuit with the average current mode control.The secondary stage uses full-bridge DC/DC converting circuit with the voltage mode control.In this paper,the design processes of switching power supply are present in detail.Firstly,all circuits are designed,including single-phase uncontrollable rectifier circuit,Boost circuit,the main circuit and control module,IGBT driving circuit and protection modules.Then,a 20k hertz switching power supply of 1100W is manufactured.The power supply uses a chip UCC28019 which is produced by TI company working in average current to achieve power factor correction.Similarly,the power supply uses a a chip SG3525 as a controller for DC/DC converting circuit.Finally,the modules are tested to verify the technique and power supply can run smoothly.