Effects of output filter on cross regulation in SRC

Abstract

An analysis is presented of the cross regulation performance of multioutput series resonant converter (SRC) topologies using multiwinding transformers. The steady-state cross-regulation characteristics are derived using state-plane techniques and illustrated by examples of two-output SRCs with capacitive and inductive filters. The characteristic curves show that over some range of output currents, the cross regulation performance of the SRC with the inductive filter is much improved over the SRC with the capacitive filter and less dependent on the tolerances in the leakage inductances and the level of loading on the unregulated outputs. The converter control characteristics of the SRC with the inductive filter are relatively unaffected by the addition of the second output. The theoretical results were verified by simulation.<>