Variable Frequency Phase-Shift Modulation Symmetrical Series-Resonant Bidirectional DC-DC Converter—Analysis and Verification of ZVS Performance and Reactive Power Minimization—

Conventional dual active bridge (DAB) converters based on the non-resonant circuit topology have sever limitation of soft switching under light load conditions without complex multi-pulse modulations such as or triple phase shift. To address this technical problem, paper explores a symmetrical series-resonant bidirectional dc-dc converter (SSR-BDC). The SSR-BDC features variable frequency shift modulation (VF-PSM) for minimization reactive power in wide range operations. CLLC series resonant tanks provide steady-state characteristics and voltage regulations forward reverse flows, which is advantageous seamless exchange flows electronics applications simple control logic. principle regulation described with frequency-domain analysis SSR-BDC, whereby theory determining most suitable angle clarified. experimental verifications 500W prototype are presented, practical effectiveness revealed; actual efficiency improves by 1.4% reduces 75% after adopting VF-PSM.