High-Gain Bidirectional LCLC Resonant Converter With Reconfigurable Capability

A reconfigurable gain circuit is proposed for an LCLC resonant converter with bidirectional capability considering wide varying redox flowbattery source. Asuitable hybrid control scheme for LCLC resonant converter with secondary synchronous rectifier is proposed in this work. The proposed reconfigurable circuit enables to configure secondary bridge as an active voltage doubler, full-bridge circuit during forward power transfer mode and reverse power transfer mode, respectively. The reconfigurability helps significantly to design a transformer with lower secondary turns and achieve desired high gain. The reduced transformer secondary turns result in reduced transformer parasitics. The presence of LCLC resonant tank helps to provide the additional gain; the hybrid control scheme ensures zero-voltage switching turn-ON for the primary, and secondary synchronous MOSFETS throughout the operating range. The proposed converter is analysed using fundamental harmonic approximation. The proposed reconfigurable gain circuit and hybrid control scheme is verified experimentally for an 800 V/1 kW hardware prototype fed from 24 to 54 V input.

Automated summary

A reconfigurable gain circuit is proposed for an LCLC resonant converter with bidirectional capability considering wide varying redox flowbattery source. A suitable hybrid control scheme is proposed for LCLC resonant converter with secondary synchronous rectifier. The proposed circuit enables the configuration of secondary bridge as an active voltage doubler, full-bridge circuit in forward and reverse power transfer modes, respectively. The reconfigurability helps in designing a transformer with lower secondary turns and achieving desired high gain. The presence of LCLC resonant tank provides additional gain; the hybrid control scheme ensures zero-voltage switching turn-ON for the primary and secondary synchronous MOSFETs. The proposed converter is analysed using fundamental harmonic approximation and experimentally verified for an 800 V/1 kW hardware prototype fed from 24 to 54 V input.