A Reconfigurable Bidirectional Isolated LLC Resonant Converter For Ultra-Wide Voltage-Gain Range Applications

This article proposes a new bidirectional isolated LLC resonant converter, which is suitable for ultra-wide voltage gain range applications, such as electric vehicle charging systems. The inverter and rectifier of proposed topology both have two modes by reconfiguring different modulation schemes during bidirectional operation. This results in three voltage-gain ranges, allowing ultrawide output voltage operation over narrow modulation frequency. The conversion ratio and resonant tank can be designed for only a quarter of the required output voltage range. Finally, the proposed topology and analysis are validated by experiments results obtained from the converter prototype built in the laboratory.