Technical Lecture Session
Transportation Power Electronics I
resonant converter, dc/dc converter
Conventional LLC is not able to maintain a good performance under an ultra-wide output voltage range. To address with this issue, a novel adjustable turns ratio transformer based LLC converter is proposed. Due to the output voltage range, the proposed topology operates under three modes, correspondingly. Each mode is assigned a specific transformer ratio. Therefore, the circuit operation in each mode can be optimized, separately. A smooth mode transition is achieved without transient issues. A 1 kW prototype with 390V input voltage to 100-420V output voltage is designed to validate the concept.