Analysis And Design Of Active Clamp Forward Converter Based On DSP

As an isolated DC/DC converter with high efficiency,high reliability and low cost,forward converter has been widely used in industrial production and residents’ life,and its performance requirements are also higher and higher.The problems of traditional forward converter such as low utilization of magnetic core,high rectifier loss of secondary side diode and inconvenient adjustment of circuit parameters under analog control are further highlighted.To solve these problems for this article DSP forward converter of synchronous rectification and soft switching technology is based on doing further research.On the basis of analyzing the working principle of traditional forward converter,this paper studies the magnetic reset of the transformer’s primary side,the soft switching of the switch tube and the output synchronous rectification technology,so as to improve the performance of the forward converter.First,by analyzing the principle of two active clamp topology on the high voltage side and the low side side,the advantages of the active clamp converter are compared with the traditional forward converter,and the active clamp topology at low voltage side is determined as the research object.Then the synchronous rectification technology and soft switching technology which can improve the efficiency of active clamp forward converter are studied.For synchronous rectification technology,by analyzing the principle of several commonly used driving modes and combining the circuit topology characteristics and design requirements of this paper,the synchronous rectification method using transformer auxiliary winding voltage is determined.For soft switching technology,by analyzing the working mode of active clamp forward converter in one cycle,the conditions that need to be satisfied for soft switching and transformer core reset are obtained.Based on the technical specifications of the converter,the parameters of active clamp forward converter circuit are designed.Finally,the main circuit and control circuit are designed with TMS320F28035 as the main control chip.The simulation model of the circuit is built in the Matlab/Simulink simulation environment,and the correctness of the parameter design is verified by simulation.Based on the theoretical design and simulation analysis,experimental design a prototype 60W through prototype testing and waveform analysis,prototype performance indicators meet the design requirements,verify the paper the theoretical analysis and design parameters.The correctness realizes the soft switching of the converter and improves the conversion efficiency.