A wind power plant including a rotor having at least one angle-adjustable rotor blade, a generator that, for generating electrical power, can be directly or indirectly coupled to the rotor and, for supplying the electrical power, can be directly or indirectly coupled to an electrical grid, at least one rotor blade adjusting device for setting an angle of the rotor blade including at least one blade adjusting drive having at least one direct-current motor that can be coupled to the electrical grid via a converter, a control device, coupled to the converter and via which the control and/or regulation of the blade adjusting drive ensues, and a direct current voltage source that ensures a power supply to the blade adjusting drive in the event of grid power failure, whereby the direct current voltage source can be directly coupled to the blade adjusting drive or indirectly to the blade adjusting drive.