A comprehensive design approach for a three‐winding planar transformer

Abstract

Abstract In this paper, a new three‐winding planar transformer design with the integrated leakage inductor is proposed for a triple‐active‐bridge converter. It enables two output voltage levels: a high voltage (HV) output port and a low voltage (LV) output port. The primary and secondary windings are split unevenly in both side legs while the tertiary winding is connected in parallel. The unique winding configuration enables: (i) enhanced efficiency with low volume; and (ii) suppressed parasitic capacitances. Detailed transformer reluctance and loss models are developed in the design process. The core geometry is optimized using a reluctance‐model‐based mathematical computation. Moreover, comprehensive high‐fidelity simulations are conducted to analyse the trade‐offs among parasitic capacitances, losses, and inductances. The customized core and the non‐overlapping winding boards are assembled, characterized, and tested under various power flow conditions.