The average model of a three-phase three-stage Power Electronic Transformer

Power Electronic Transformer (PET) has been the focus of interest for many years. The PET opens up the possibility to replace bulky low-frequency transformers, and has more functions and better performance. In this paper, the model and the control strategy of a three-phase three-stage PET are analyzed, and its average model is derived to increase the simulation speed. However, the average model would miss a special current distortion as it neglects the voltage drop of the switches, which limits the effective range of the average model.