270 kVA Solid State Transformer Based on 10 kV SiC Power Devices

With the advancement of semiconductor technology, solid state transformer (SST) with high voltage fast switching SiC power devices is becoming a valid option to replace the conventional transformers in power substation. In this paper, a 270 kVA solid state transformer based on 10 kV SiC power MOSFET has been proposed. The two stages of SST, five-level Vienna rectifier and five-level DC/DC converter are specifically designed and simulated in closed loop. The analysis of device losses is performed based on the device characteristics. A design of high frequency transformer is presented as well. The simulation results together with the loss analysis verify the functionality and feasibility of SST.