An Optimal Design of a Hybrid Liquid/Air Cooling System for High Power, Medium Frequency, and Medium Voltage Solid-State Transformer

In this paper, a 10 kV SiC MOSFET-based solid-state transformer (SST) operating at 13 kV to 7.2 kV, 667 kW, and 20 kHz is modeled and optimized to reach maximum power density and efficiency. In order to reach optimum configuration, different core material/type/size, primary/secondary turns, insulation type/thickness, and cooling systems are considered; then based on a systematic approach the best solution is obtained. To reach this goal, the magnetic part of SST forced air-cooling, and the water-cooling system is modeled in ANSYS MAXWELL/Simplorer, ANSYS-ICEPAK, and ANSYS-FLUENT, respectively. The simulation results show a high efficient SST with an effectiveness of the cooling system.