Patent ID: 8338978

Claim:
A wind power plant that includes a wind turbine generator that supplies electric power to a utility grid, the wind turbine generator being connected to a plurality of blades, and an electrical storage device that is charged by electric power produced by the wind turbine generator or electric power supplied from the utility grid and that supplies electric power to the utility grid through discharging, the wind power plant comprising: a wind-turbine control section that performs for the wind turbine generator, a normal operation having a normal rotational speed of the blades, and generating a normal electric power, an acoustic-noise suppression operation in which a rotational speed of the blades is controlled to a speed less than the normal rotational speed in the normal operation in order to suppress acoustic noise generated through rotation of the blades, and an over power operation in which the rotational speed of the blades is controlled to a speed greater than the normal rotational speed in the normal operation to generate electric power greater than the normal electric power generated in the normal operation; and an electrical-storage-device control section that causes the electrical storage device to be charged or discharged, based on a difference between an output power obtained when the acoustic-noise suppression operation is performed and a demanded output power demanded from the utility grid, wherein when the acoustic-noise suppression operation is not performed, the wind-turbine control section makes the wind turbine generator perform the over power operation by increasing the rotational speed of the blades higher than the rotational speed of the blades in the normal operation, and when the wind turbine generator is made to perform the over power operation, the electrical-storage-device control section causes the electrical storage device to be charged by electric power corresponding to a difference between the output power produced in the normal operation and the output power produced in the over power operation.