Non-resonant coupled parallel resonant converter

A resonant converter using nonresonant coupling between the rectifier and resonant circuits is presented. This converter has many advantages over a conventional parallel resonant converter (PRC), such as better control characteristics, lower component stress, lower converter gain, and better stability. It uses a capacitive (instead of an inductive) output filter, which has the advantages of smaller physical size and less component cost. Analysis and design of this converter are given for three modes of converter operations. By comparing the characteristic curves with those of the conventional PRC, it is seen that the present converter has a lower converter gain for a given Q_p. This present converter should have better stability than the conventional PRC. Since the capacitor voltage is clamped at ±V₀, the size of the state-plane diagram is limited for a given gain. This assures that a runaway problem in the converter is not encountered