This presentation introduces a novel transformer design to address the voltage imbalance issue for an LLC converter with multiple transformers in series to support a wide output voltage range. In the presentation, the proposed transformer design is implemented on a digital controlled SiC based 60kW prototype. Identical voltage balance is achieved in a three phase LLC converter with a wide output voltage range. A digital controlled SiC-based prototype with a switching frequency of 125kHz-250kHz is demonstrated with 200Vdc-1000Vdc output voltage range and exceeding 98% in peak efficiency.
