Grid-tied power supply system and related device thereof

A grid-tied power supply system includes a controller and at least two inverters. One inverter is coupled to a plurality of power supply modules. The controller is configured to determine a power parameter. The inverter receives a power control packet through a communication transmission medium, determines target power based on the power parameter carried in the power control packet, and determines, based on the power control packet and/or the communication transmission medium, a target adjustment manner corresponding to the power control packet from at least two adjustment manners. The inverter further adjusts, to the target power in the target adjustment manner, power to be output by the inverter to an alternating-current (AC) power grid. The inverter can directly adjust power to be output by the grid-tied power supply system to the alternating-current power grid.