Abstract: The present disclosure relates to methods for operating wind turbines (10), in particular to methods for feeding wind turbine auxiliary systems when connection to the electrical grid (102) is lost. A method (100) comprises rotating a wind turbine rotor (18) at a first rotational speed by actively controlling a pitch angle of the plurality of rotor blades (22) while a safe condition is detected, and generating electric power; supplying at least part of the generated electric power to at least one wind turbine auxiliary system; detecting a specified condition; and in reply to the detection of the specified condition, rotating the wind turbine rotor (18) at a second rotational speed lower than the first rotational speed, and generating electric power.

Abstract: The present disclosure relates to methods for operating wind turbines (10) and charging one or more auxiliary power sources (84) for providing auxiliary power to one or more wind turbines (10). A method comprises pitching the wind turbine blades (22) to a predetermined idling pitch angle such that the wind turbine generator (42) produces power for charging one or more auxiliary power sources (84) above a predetermined wind speed. The method further comprises keeping the pitch angle (25) of the blades (22) at the idling pitch angle and charging the auxiliary power sources (84) when a prevailing wind speed reaches or exceeds the predetermined wind speed.

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: A method for operating a wind farm having a string (S1-S3) of wind turbines (100-100c) which are electrically connectable with each other and a grid (510, 550) is disclosed. Each wind turbine includes a rotor (106) with rotor blades (108), a power conversion system (118, 210, 238) mechanically connected with the rotor (106), and at least one auxiliary subsystem (105, 109).

Abstract: An infrastructure arrangement for use in an underwater power generation installation includes a support structure adapted for engagement with a bed of a body of water, and an infrastructure module adapted to house infrastructure equipment for connection to power generating units of the installation. The infrastructure module is releasably engageable with the support structure.

Abstract: A water-based power generating installation includes a water based power generating device operable to derive power from a body of water, and to export that power via a power export cable, and an infrastructure arrangement for providing a power export connection from the installation, and including infrastructure equipment for the installation, which infrastructure equipment serves to connect the power generating device with the power export connection.

Abstract: A water-based power generating installation includes a water based power generating device operable to derive power from a body of water, and to export that power via a power export cable, and an infrastructure arrangement for providing a power export connection from the installation, and including infrastructure equipment for the installation, which infrastructure equipment serves to connect the power generating device with the power export connection.

Abstract: An infrastructure arrangement for use in an underwater power generation installation includes a support structure adapted for engagement with a bed of a body of water, and an infrastructure module adapted to house infrastructure equipment for connection to power generating units of the installation. The infrastructure module is releasably engageable with the support structure.

Abstract: The generator uses a permanent magnet electrical machine providing three phase, unregulated DC voltage, from three windings feeding a rectifier circuit. A capacitor across the DC voltage acts as a buffer between the DC supply and the load. Regulation of the DC supply seen by the load is achieved by a switch in parallel with the DC voltage and with the load. The switch allows current to be drawn by the capacitor or load from the windings, or shorts the windings. The inductance of the windings makes it safe to short them. A blocking diode prevents current returning from the capacitor when the switch is closed. The result is a regulated DC output of adequate quality for e.g. aerospace applications and with low component count and complexity.