Medium-voltage direct-hanging type energy storage conversion system and start-stop control method thereof

The invention discloses a medium-voltage direct-hanging type energy storage conversion system and a start-stop control method thereof, and the system comprises a high-voltage AC device electrically connected with an AC power grid and a low-voltage DC device electrically connected with an energy storage end, and the high-voltage AC device and the low-voltage DC device are electrically connected through a high-frequency transformer; the high-voltage alternating-current device adopts a three-phase star-shaped wiring mode, each phase is formed by connecting double-H-bridge power modules in series, and the low-voltage direct-current device is formed by connecting single-H-bridge power modules in parallel. A common high-frequency bus structure is adopted, the number of modules of the high-voltage alternating-current device and the number of modules of the low-voltage direct-current device are different, flexibility is high, compared with a chain type structure, the number of devices of the converter and electric en