To overcome the deficiencies in current-sharing performance and operating adaptability of parallel-connected multiphase LLC resonant converter systems

conventional passive current-sharing topologies based on common-inductor or common-capacitor coupled resonant tanks realize autonomous current balancing via the mutual coupling of resonant inductors or capacitors. However

both approaches rely on the introduction of additional heterogeneous impedance capacitive coupling for the common-inductor topology and inductive coupling for the common-capacitor topology to realize ideal current sharing performance. This dependency leads to structural complexity and unsatisfactory performance in phase shedding operation and fault isolation

making it difficult for them to be applied in high-reliability scenarios. In this paper

a novel common inductor-capacitor type passive current sharing topology and its improved structure are proposed. By flexibly introducing coupling impedance between the resonant branches of each module

the proposed schemes achieve efficient energy coupling among the resonant networks

thereby overcoming the limitations of traditional topologies that require auxiliary impedance for optimal current sharing. The new topologies not only significantly enhance current balancing in parallel LLC systems

but also demonstrate excellent phase shedding and fault isolation performance

greatly improving system reliability and engineering adaptability. Theoretical analysis and simulation results verify the superior current sharing and high reliability of the proposed structures over a wide load range. This paper provides a solid foundation for topology optimization and engineering implementation of high-performance LLC parallel systems.