Optimal Design of RCD Parameters in Flyback Converter

To obtain the optimal design method of RCD in flyback converter, the influence of the clamp voltage VC on the feedback energy Wf generated by the feedback voltage Vf was analyzed. It is indicated that VC must be larger than Vf and Wf decreases with the increment of VC. The energy Wlk from the leakage inductor was researched, let Wf=Wlk, the critical clamp voltage VCK was obtained, on this basis, the optimal design methods of the RCD parameters were proposed. The validity of theoretical analysis and the design methods were verified by the simulation and experimental results.