Identification of steady-state operational modes of the series resonant DC-DC converter based on loosely coupled transformers in below-resonance operation

This paper identifies all the steady-state operational modes of a series-loaded resonant DC-DC power converter (SRC) in below-resonance operation, taking into account the coupling quality of the isolating transformer. A novel operational plane is defined, and ten operational modes are identified in this plane. Borders between neighboring domains of these operational modes are analytically defined. Results are given in normalized form and experimentally verified.