An energy feedback control of series resonant converter

An energy feedback control utilizing the resonant tank energy as a control law is proposed to improve the stability and dynamic characteristics of the series resonant converter (SRC). The control eliminates the effort of sensing DC voltages from the optimal trajectory control (OTC). The implementation of this control is therefore simpler than that of the OTC. A discrete time domain modeling for the energy feedback controlled SRC is performed in a step-by-step procedure, and the root locus technique is applied to the analysis of the stability and dynamic characteristics of the controlled system. In the root locus analysis, the eigenvalues of the controlled system vary according to the energy feedback gain ratio. Design guidelines which can be used to select this ratio are presented. The energy feedback controller was implanted and tested in conjunction with a full-bridge SRC, and the experimental results show good agreement with the theoretical analysis.<>