A Novel High Insulation 100 kW Medium Frequency Transformer
Zhicheng Guo, Sanjay Rajendran, Jagadeesh Tangudu, Yasmin Khakpour, Stephen Taylor, Lei Xing, Yue Xu, Xianyong Feng, Alex Q. Huang
Abstract
High voltage insulation and thermal management are the two major challenges in a high-power medium frequency transformer (MFT) design. This letter proposes novel insulation and cooling structure with potted windings in a 100 kW MFT with two FINEMET FT-3TL magnetic cores and parallel-concentric winding structure. For the first time, a three-dimensional printed bobbin with heatsink fins is demonstrated. The 100 kW MFT achieves a power density of 10.6 kW/L and a partial discharge inception voltage of 20 kV peak. The MFT is applied in a dual active bridge based medium voltage solid state transformer, achieving a peak efficiency of 98.2% at 40 kW and 97.5% at 100 kW. The MFT itself has a 99.735% efficiency with superior thermal performance at 100 kW output power.