Power generation system and plant control device

This power generation system is provided with: a plurality of power conversion devices for converting DC power from a DC power supply to AC power; and a plant control device for controlling the plurality of power conversion devices. The plant control device includes a virtual synchronous generator model unit for outputting power command values on the basis of the current and voltage values at a system interconnection point on the output side of the plurality of power conversion devices. The plurality of power conversion devices output AC powers according to the power command values. The plurality of power conversion devices may include a first power conversion device and a second power conversion device. The DC power supply to which the first power conversion device is connected may be a renewable energy generation device, and the DC power supply to which the second power conversion device is connected may be a storage battery. The DC power supply to which each of the plurality of power conversion devices is connected may be a DC power supply in which the renewable energy generation device that is a first DC power supply and the storage battery that is a second DC power supply are connected in parallel with each other.