A method for controlling an inclination of a floating wind turbine platform to optimize power production, or to reduce loads on the turbine, tower, and platform, or both, includes receiving data associated with the inclination of the floating wind turbine platform and wind speed and direction data. An angle of difference between the turbine blade plane and the wind direction is determined, where the angle of difference has a vertical component. A platform ballast system is then caused to distribute ballast to reduce the vertical component to a target angle chosen to optimize power production, or reduce turbine, tower, and platform loads, or both.

A turbine comprises a shaft (20), a mass (10) eccentrically mounted for rotation about shaft (20), having its center of gravity at a distance from the shaft (20) and a motion base (15). Motion base (15) rigidly supports the shaft (20), and is configured for moving the shaft (20) in any direction of at least two degrees of movement freedom, except for heave. A floating vessel-turbine (120), encloses entirely the eccentrically rotating mass (10) and the motion base (15). The turbine converts ocean wave energy into useful energy, very efficiently.

An acoustic monitoring system and method for the health status of an offshore wind turbine and an ocean wave are provided. The acoustic monitoring system includes a first laser transmitter, a second laser transmitter, a telephoto camera provided at a hub, a vibration detection sensor provided on a tower of a wind turbine, and four acoustic detection sensors arranged at an interval of 90° along the circumference of the tower. The first and second laser transmitters are arranged at the bottom of a nacelle of the wind turbine and emit laser lights vertically downward. The first laser transmitter, the second laser transmitter, the telephoto camera, the vibration detection sensor, and the acoustic detection sensors are connected to a data acquisition and conversion module through a transmission module. The acoustic monitoring system combines laser light detection with acoustic signal feature detection to improve stability and safety of the offshore wind turbine.

A floatable offshore structure, in particular a floatable offshore wind turbine, includes at least one floatable foundation with at least one floating body. The offshore structure further includes at least one anchoring arrangement configured to fix the offshore structure to an underwater ground in an anchoring state of the offshore structure. The anchoring arrangement includes at least one anchor connection between an anchor and the floatable foundation and at least one position stabilization device configured to change the length of the anchor connection between the anchor and the floatable foundation in the anchoring state based on at least one attitude parameter of the offshore structure and at least one attitude set point parameter.

A method for controlling an inclination of a floating wind turbine platform to optimize power production, or to reduce loads on the turbine, tower, and platform, or both, includes receiving data associated with the inclination of the floating wind turbine platform and wind speed and direction data. An angle of difference between the turbine blade plane and the wind direction is determined, where the angle of difference has a vertical component. A platform ballast system is then caused to distribute ballast to reduce the vertical component to a target angle chosen to optimize power production, or reduce turbine, tower, and platform loads, or both.

The present disclosure is directed to a method for responding to a friction coefficient signal of a pitch bearing of a pitch drive mechanism of a wind turbine and/or for controlling the pitch drive mechanism(s) and/or a bank of ultracapacitors. The method and system include: accessing high-frequency measurement data of the at least one pitch bearing; estimating, via a torque balance model implemented by a controller, a frictional torque of the at least one pitch bearing based, at least in part, on the high-frequency measurement data; estimating, via the controller, a friction coefficient signal of the at least one pitch bearing based, at least in part, on the frictional torque; comparing the friction coefficient signal with a friction threshold; determining whether the friction coefficient signal deviates from the friction threshold based, at least in part, on the comparison; and, if so, acting.

A method for operating an asynchronous doubly-fed wind turbine generator connected to a power grid in a grid-forming mode to emulate a virtual synchronous machine. The doubly-fed wind turbine generator includes a line-side converter coupled to a rotor-side converter via a direct current (DC) link. The method includes receiving, via a controller, at least one reference command from an external controller. The method also includes controlling rotor flux of the doubly-fed wind turbine generator using the at least one reference command. Further, the method includes providing power droop control for the doubly-fed wind turbine generator through at least one of rotor-side reference frame rotation and d-axis flux control.

The present invention relates to methods, controllers and computer program products for determining an optimal tilt angle for a wind turbine. One or more signals indicating site conditions at and/or near a wind turbine are received 402 and an optimal tilt angle for said wind turbine based on said received one or more signals indicating site conditions is determined 403. The optimal tilt angle is then transmitted 404 to a platform controller such that said wind turbine can be inclined said optimal tilt angle.

The present invention relates to a method and a wind turbine structure for optimising the weight of the wind turbine and the offshore foundation. The wind turbine is operated based on the measured wave height which in turn allows the tower height to be reduced so that the ratio between the tower height and the length of the wind turbine blades is greater than 0.5. The rotor is parked in a predetermined position with a maximum or minimum clearance between the tip end of the wind turbine blades and the sea level if the measured wave height exceeds a predetermined threshold. A monitoring unit arranged relative to the wind turbine detects if one or more objects are located within a monitoring area. If an object is located within the monitoring area, the wind turbine is shut down and the rotor is rotated to the parked position.

A dynamic adaptive mooring system for wave energy converters (WEC) is disclosed that has a mooring configuration that has a set of fixed mooring lines, and a set of movable mooring lines. When an incoming wave train interacts with the fixed WECs, a set of wave interference points that have higher wave amplitudes than the incoming wave train are formed downstream of the fixed WECs. The movable WECs are then positioned at the interface points to optimize wave energy transfer.