The Design Of Base Station Power Supply Based On A Full-Bridge LLC Resonant Converter

At present,the switching power supply technology was quickly development.With the correlation topology is emerging.Optimization and innovation gradually becomes the trend of the high efficiency and high power density.Soft switching technology was widely researched by professional person.So less switching loss,high power density,high energy conversion efficiency,and especially suitable for high power occasion technology,namely Full-bridge LLC resonant converter gradually attract the researchers’ attention.The high-efficiency converter was applied to the base station power supply.It not only save energy, but also optimizes the power efficiency.This paper detailed analysis The Full-bridge LLC resonant converter working principle,and then designs main circuit and control parts.Finally,accomplish a 48V/12A Full-bridge LLC resonant converter.The main work and conclusion of this paper can be summarized as the following five aspects:(1) Research on Full-bridge LLC resonant converter topology and characteristic.On this basis, not only the working principle but also the frequency characteristic, no-load characteristic and short-circuit characteristic of the converter are introduced and discussed in detail.At moment,the function of the main parameters of this resonant converter is described and analysis in working condition.(2) The main circuit of the Full-bridge LLC resonant converter was achieved.According to the parameters of this converter,the main circuit parameters of Full-bridge LLC resonant converter was optimal designed,including Resonator parameters,power switch,high frequency transformer,output rectifier diodes and filtering capacitor and so on.(3) Control part circuit was designed based on MC33067 of high efficiency chip.The resonant converter is controlled by this chip,and used their characteristics change the current to control the nature of the internal pressure cavity oscillator frequency.And then,the main circuit,drive circuit,and chip itself parameters was fulfilled.The output voltage of high quality was obtained.(4) Digital control circuit was designed based on DSP.The resonant converter is controlled by TMS320F28035.The method about design of this control circuit was given by DSP digital PI control sampling voltage algorithm.(5) The circuit was simulated by Saber2010 and the prototype was manufactured.Using Saber2010 software through filled the necessary parameters to simulates this converter.Then,we should adjust circuit constantly,simulation,to reasonable design of the dead time to avoid the problem of straight,to solve the problem of no-load voltage and other issues.By observing the simulation results,the simulation was analyzed, and a prototype of 48V/12A output was tested, the performance of the resonant converter is as follows:the efficiency is up to 96%.The result meets the design requirement.In this paper,Using different methods to control the Full-bridge LLC resonant converter,which makes the resonant converter to obtain some characteristics about higher efficiency, small size and light weight. At present, it was a wide range of applications in the field of base station power supply.