Method of operating a wind power plant during a grid loss

The disclosure concerns a wind power plant (1) and its operation during grid loss, wherein the wind power plant (1) comprises a plurality of rotor blades (2), a blade pitch drive (3), a rotor shaft (4), an electric generator (5), and a control unit (6) for controlling the operations of the wind power plant (1), wherein the plurality of rotor blades (2) are rotatably connected to the rotor shaft (4), such that the pitch of the rotor blades (2) can be adjusted by the blade pitch drive (3) under the control of the control unit (6), and wherein the rotor shaft (4) is operatively connected to the electric generator (5) for generating electric energy, the wind power plant (1) further comprising an energy storing unit (9) for powering the blade pitch drive (3), wherein the control unit (6) comprises a control module (7) for adjusting the rotor blades (2) and for entering a self-sustaining mode of operation of the wind power plant (1). With the self-sustaining mode of operation basic functions of the wind power plant (1), in particular safety and security functions as well as lubrication of the rotatable parts (2, 3, 4, 5, 8) of the wind power plant (1) are sustained even for long periods of a grid loss.