Development Of Interleaving Two-Transistor Forward Converter With Power Factor Correction

It is the development trend to achieve light and thin and small switching power supply. One of the important issue directions is to do research on high-efficiency, high power density, high reliability. The harmonic pollution to power grid is becoming worse with the wide application of power electronic devices. It is imperative to eliminate harmonic pollution and achieve green power supply. A600W, dual-stage prototype of interleaving two-transistor forward converter with power factor correction (PFC) is developed in this paper.The background and significance of this paper is analyzed firstly. The research status is summarized and organized. The main work is introduced. The operation principle of forward converter is analyzed with the12operation mode in a switching cycle. The advantages and disadvantages of the converter are summarized. Based on one-cycle control (OCC), the implementation process of pre-stage Boost PFC circuit is described. After the analysis of the advantages and disadvantages of voltage control and current control, a double-loop control strategy in the form of voltage control outer loop and peak current control inner loop is adopted. The small-signal analysis of the main circuit is build, in order to get the first-order mode of peak current control. The design of the whole system is calculated in detail. The control circuit is also designed with OCC chip IR1150and peak current control chip UC3846.The simulation of Boost PFC circuit and forward circuit are achieved with Saber, which proving the right design. At last, a prototype is completed, the result of the experiment is analyzed, and the expected design goal is achieved.