Direct-current distributed power supply system based on three-port converters and control method thereof

The invention discloses a direct-current distributed power supply system based on three-port converters and a control method thereof, and belongs to the field of power electronic conversion and distributed power supply systems. The system comprises a direct-current input power supply (10) and a power conversion unit (20), wherein the direct-current input power supply (10) is composed of N subordinate direct-current input power supplies, the power conversion unit (20) is composed of N subordinate three-port converters, and N is a natural number larger than 1; each subordinate direct-current input power supply is connected with one subordinate three-port converter in series, the output ends of all the subordinate three-port converter are connected to an output end voltage bus, and the energy storage ends of all the subordinate three-port converters are connected to a storage end voltage bus. The energy storage end current sharing strategy is adopted when an energy storage device is in the discharging state, the hybrid power control strategy of distributing output end power according to the power of the input power supplies is adopted when the energy storage device is in the charging state, and then stable and reliable operation of the system can be achieved.