A 10kW/ 200kHz PCB- Winding Transformer with High Insulation Voltage for Solid-State Transformer Applications

In a solid-state transformer (SST), the transformer with high insulation voltage is one of the most important components. The PCB-winding transformer is one promising candidate because of the high dielectric strength of PCB materials, the capability of high-frequency operation, and the standardized manufacturing process. In this paper, a novel high-frequency, high-insulation PCB-winding transformer is proposed. A partially interleaved PCB-winding structure is adopted to reduce the winding loss, and a partially potted structure is introduced to improve the insulation capability. The novel partially potted structure also features a much lower temperature rise compared to the fully potted case. A 10 kW/200 kHz prototype is built to verify the functionality and insulation capability. An excellent 10.5 kV rms/14.85 kV peak partial discharge inception voltage (PDIV) is achieved. The prototype was demonstrated in a 400 V/400 V, 10 kW, 190 kHz LLC converter, with a maximum temperature of 90 degrees C at thermal equilibrium.