This paper aims to analyze the control technology of Power Electronic Transformer (PET) using DSP software. With two-stage cascaded power electronic transformer as study case, the H-bridge grid parallel is used to analyze the control conditions of the back stage inverter, prime and intermediate separator. It is found by experimental simulation analysis that the H-bridge parallel method proposed in this study has a certain applicability and can play a useful control effect on power electronic transformer. In the end, we conclude that the DSP-based control technology for PET has a certain exploration and application value.