Auxiliary power supply for solid state transformer with ultra high voltage capacitive driving

This paper proposes an auxiliary power supply (APS) for solid state transformers (SST), which is able to handle extremely high input voltage. Input series output parallel (ISOP) structure is used and only one controller IC is adopted to regulate the output voltage, which simplifies the structure and reduces the cost effectively. Capacitive driving is used to drive multiple switches in different modules of the APS. The proposed capacitive driving method is able to transfer gate signal and driving energy simultaneously even for thousands of volts, which largely reduces the cost and size of the APS. Finally the proposed auxiliary power supply is verified and demonstrated through a 12W prototype.