Since the second decade of the new century,the highly integrated electronics industry has developed rapidly,and electronic equipment has also become an indispensable part of our production and life.It has also become more refined,and the research of switching regulator converters applied in high-power,low-voltage,high-current,high-efficiency and smallvolume applications has become more popular.In response to the above specific requirements,this paper improves the topology and control method of the traditional bridge converter,researches and designs a DC / DC converter.First of all,according to the design requirements,this paper conducts a comparative screening of medium and high power converters,sums up and determines the mainstream full-bridge structure type;introduces the various ways that the converter improves internal efficiency,determines the phase shift control method;then compares For traditional analog control,several advantages of digital control are proposed.Secondly,on the basis of the above analysis,this paper first conducts a step-by-step analysis of the working principle of the phase-shifted full-bridge current doubler synchronous rectifier converter,understands its current doubler working principle,synchronous rectification timing,and calculates the phase shift control The conditions for realizing the zero-voltage turn-on,and finally the detailed topology analysis and formula derivation of the proposed topology.In this paper,because of the digital control mode,the simplified iterative model is used to establish a discrete iterative model of the system,considering the influence of parasitic parameters in the circuit,combined with the state transfer equations and control parameter equations,to obtain the trajectory of its characteristic roots with the control parameters.The trend graph determines the relationship between critical parameters and input and output parameters,and finally determines the appropriate control link parameters,so that the overall system can run stably and reliably,with good steady-state and dynamic characteristics.Finally,combined with the previous theoretical analysis,simulation and experimental verification are carried out on the phase-shifted full-bridge current doubler synchronous rectifier converter.According to the given conditions of the system,the hardware parameters of the main power loop and the control loop are designed and the device model is determined.The PCB board is laid out reasonably.The design of the overall software system of the converter and the writing of the relevant codes of each part are completed.The experimental prototype platform was built to verify the correctness and effectiveness of the theoretical analysis. |