A power generation system is provided. The system includes a bus, at least two converters, an energy-type energy storage unit (ES), a power-type energy storage unit (PS) and a controller. The ES and the PS are coupled in parallel to the bus through corresponding converters of the at least two converters. The controller is configured to control the ES and the PS through the corresponding converters in at least two conditions during a charging mode and a discharging mode: when a power for the ES and PS is below a power threshold, control the power to flow between the ES and the bus; and when the power is above the power threshold, control a part of the power to flow between the ES and the bus and another part of the power to flow between the PS and the bus. And a method for generating power is also provided.