Abstract: The present disclosure relates to methods (100, 200) for operating in wind farm grids (108) of wind farms (105) which are electrically disconnected from a utility grid (102), for example wherein communication with a wind farm controller (109) has been lost. The present disclosure further relates to wind farms (105), wind farm grids (108) and wind turbines (10). A method (100) comprises operating one or more first wind turbines (111) to generate electrical power with predetermined electrical characteristics when the wind farm (105) is disconnected from a utility grid (102), and delivering the electrical power with the predetermined electrical characteristics to the wind farm grid (108); and one or more second wind turbines (112) detecting (120) the electrical power delivered to the wind farm grid (108) and determining that the wind farm (105) is disconnected from the utility grid (102) by identifying the predetermined electrical characteristics.

Abstract: A method for operating a wind farm having a string (S1-S3) of wind turbines (100-100d) which are electrically connectable with each other and a grid (510, 550) via power connections (Cab-Cd) is disclosed. Each wind turbine includes a rotor (106) with rotor blades (108), and a power conversion system (118, 210, 238) mechanically connected with the rotor (106). The method includes disconnecting the string (S1-S3) from the grid (510, 550), and identifying a primary wind turbine (100a, 100c) of the disconnected string (S1-S3) which is electrically connectable with at least one secondary wind turbine (100b-10d) of the disconnected string (S1-S3). The power conversion system (118, 210, 238) of the primary wind turbine (100a, 100c) includes a reactive power capability (RPC) that at least matches a reactive power (RP) of a cluster (C1, C11, C12) to be formed by electrically connecting the primary wind turbine (100a, 100c) with the at least one secondary wind turbine (100b-100d) of the disconnected string (S1-S3).

Abstract: The invention concerns a method for controlling a hybrid power generation plant comprising a plurality of power sources among a hydro plant, a solar plant and a battery storage system, said method comprising: receiving from a grid to which the plant is connected at least one data among a power demand, a peak hour, a frequency, a ramp, a reactive power, a voltage; varying a power production of at least one of the plurality of power sources, depending on said at least one data received from the grid and at least one characteristic of each of said plurality of power sources.