An Improved Partially Interleaved Transformer Structure for High-Voltage High-Frequency Multiple-Output Applications

This paper proposes an improved partially interleaved structure for high-voltage (several kV) high-frequency (several hundred kHz) multiple-output applications. The proposed transformer structure is compared with other typical structures with the leakage inductance, ac capacitance, ac resistance, and the ratio of ac-dc resistance taken into consideration. The proposed structure features lower leakage inductance, smaller ac capacitance, lower ac resistance, and lower ratio of ac-dc resistance, which is suitable for high-frequency high-efficiency applications. A planar transformer with the proposed structure was built and tested in an LCLC resonant converter, where the input voltage is 40 V, the output is 4800 V, the switching frequency is 500 kHz, the output power is 288 W, and the efficiency is 96.8%, which validates the analysis.