Research On Three-terminal Structure PFC Based On Dual-MOSFET Forward Converter

In the single-stage PFC converter, the input power factor can becorrected and the output voltage is quickly adjusted, and its topologystructure has a lot of advantages such as the simplicity, the low cost, so itwill be applied widely. But the voltage of the energy storage capacitor ischanged followed by the change of the input voltage and its load in thePFC circuit. Therefore, the first problems can be solved that how tocontrol the voltage of the energy-storage capacitor and how to implementelectrical isolation between the input and the output in the single-stagePFC converter.The three-terminal structure PFC based on Dual-MOSFET forwardconverter is studied in the issue. First of all, the topology structure andoperating principle of the Boost-type single-stage PFC converter and theDual-MOSFET forward converter are analyzed in the paper; then onenew single-stage PFC converter structure is proposed that is thethree-terminal structure PFC based on Dual-MOSFET forward converter.Second, its topology structure and the working process of thevarious modal in steady state are mainly analyzed, and at the same time,its operating principle and control method are analyzed in detail.Third, its simulation circuit of PFC converter structure is set upbased on the simulation software——Saber, then the main circuit and thekey modules are simulated, the closed-loop simulation is carried out forthe whole circuit, the operating waveforms and simulation results areanalyzed, thus the correctness of the above theoretical analysis is verified.Then, the prototype of three-terminal structure PFC based onDual-MOSFET forward converter is designed according to the theoreticalanalysis and simulation results, such as the main circuit, high frequencyisolation transformer, PWM control circuit, the drive circuit module, andthe parameters of the main component and the device selection are givenseparately. The PCB circuit diagram is drawn according to the principleof the simulation diagram.Finally, the prototype is tested, and then the measured waves such as the switch tube waveform, the transformer second-side waveform, theinput voltage and current waveform, and the output voltage waveformsare analyzed in detail, thus the correctness of the theoretical analysis andsimulation analysis are verified. Based on the above power factor andefficiency test of the prototype, the results show that the performance ofthe prototype has met the requirement of design.At the end of the paper, a summary of the research work and someadvice for the following job are carried out.