Analysis of Power Transmission Characteristics of a Novel Secondary Side LCD Series Forward Converter

Abstract

A novel secondary-side LCD series forward converter is proposed, and the power transmission characteristics of the excitation inductance of the proposed converter under different modes are analyzed. By analyzing the relationship between the transmission power of forward branch and additional branch and excitation inductance, it is concluded that when the excitation inductance Lm works in CCM (continuous conduction mode), the transmission power of forward branch and additional branch has nothing to do with the value of excitation inductance. When the excitation inductance Lm works in DCM (discontinuous conduction mode), the transmission power of forward branch increases with the increase of excitation inductance, while the transmission power of additional branch decreases with the increase of excitation inductance. At the same time, the influence of power distribution on the efficiency of transformation topology is explored, and the relationship between the transmission power of the forward branch and the current stress of the switching tube was derived, and the parameter design method of magnetic element is put forward. Finally, the circuit model of the novel secondary side LCD series Forward converter is established, and the experimental results verify the correctness of the theoretical analysis and the feasibility of the parameter design method.