A Series Diode Method of Suppressing Parasitic Oscillation for Boost PFC Converter Operated in Discontinuous Conduction Mode

When a boost power factor correction converter operates in a discontinuous conduction mode, the nonzero characteristic of the average current in oscillation period and the initial value of the inductor current in a switching cycle are the main cause of the influence of the parasitic parameters on input current distortion. The effect of parasitic parameters oscillation is analyzed in detail, and a new method of series diode is proposed, which can effectively decrease the input current distortion and improve the power factor. Selection principles of series diode are given. Experimental results verify the correctness and the feasibility of the theoretical analysis.