Analysis of Energy Transmission and Design of Additional Capacitance for a Novel Secondary Side Parallel LCD Forward Converter

Abstract

For the deficiency of low utilization ratio of transformer excitation energy, complex circuit structure, low efficiency and low output power in the existing magnetic reset technology, a secondary parallel LCD forward converter which can avoid reverse charging of additional capacitor is proposed. According to the different working modes of inductors in the proposed converter, the converter is divided into different combined working modes, and the working principles of different combined working modes are analyzed in detail. At the same time, the influence of additional LCD circuit on the performance of the proposed converter is deeply studied based on the working principles of different combination modes. According to the performance analysis, the analytical expression of additional capacitance on the working mode is derived, and the optimal design scheme of additional capacitance parameters is put forward. Finally, in order to verify the effect of the additional capacitance C2 on the operation mode of the converter, an experimental analysis of the secondary parallel LCD forward converter which can avoid the reverse charging of the additional capacitor is carried out. The experimental waveform analysis verifies the correctness of the theoretical analysis and the feasibility of the design method of the additional capacitor parameters.