Provided is a method of monitoring the structural integrity of a supporting structure of a wind turbine, which method includes the steps of determining a fore-aft tower oscillation frequency; determining a side-to-side tower oscillation frequency; computing a working structural indicator value from the fore-aft tower oscillation frequency and the side-to-side tower oscillation frequency; comparing the working structural indicator value to a reference working structural indicator value; and issuing an alarm if the difference between the working structural indicator value and the reference structural indicator value exceeds a predefined threshold. Also provided is a system for monitoring the structural integrity of a supporting structure of a wind turbine, a wind turbine, and a computer program product for carrying out the steps of the inventive method.

Provided is a method of monitoring the structural integrity of a supporting structure of a wind turbine, which method includes the steps of determining a fore-aft tower oscillation frequency; determining a side-to-side tower oscillation frequency; computing a working structural indicator value from the fore-aft tower oscillation frequency and the side-to-side tower oscillation frequency; comparing the working structural indicator value to a reference working structural indicator value; and issuing an alarm if the difference between the working structural indicator value and the reference structural indicator value exceeds a predefined threshold. Also provided is a system for monitoring the structural integrity of a supporting structure of a wind turbine, a wind turbine, and a computer program product for carrying out the steps of the inventive method.

A control system for a floating offshore wind turbine (FOWT). The FOWT includes a floating base, a tower, a nacelle, and rotor with blades that harvest energy from wind passing the FOWT. Without a rigid support, however, the FOWT is able to move. The controller uses generator speed and platform pitch position of the FOWT as inputs and manipulates blade pitch and torque resistance to achieve stability.

A system and method are provided for determining deflection of a tower of a wind turbine, the wind turbine including a nacelle with a machine head and a rotor atop of the tower. A fixed location relative to the tower is established, and a total deflection of a geographic location (geo-location) of the fixed location is determined. Components of the total deflection are determined that are generated by non-thrust loads acting on the tower. The non-thrust loads deflection components are subtracted from the total deflection to determine a thrust loads deflection component corresponding to deflection of the tower from operational thrust loads on the rotor.

The invention provides a method of determining tower top acceleration of a wind turbine. The method includes receiving acceleration data from a plurality of acceleration sensors positioned in a nacelle of the wind turbine, including data indicative of a measured acceleration in a direction along at least one measurement axis of each respective acceleration sensor at a current time step. The method includes determining a predicted tower top acceleration of the wind turbine tower at the current time step, the predicted tower top acceleration being determined in dependence on a kinematic model of the wind turbine, and on a determined estimation of tower top acceleration at a previous time step. The method includes determining an estimated tower top acceleration of the wind turbine tower at the current time step by updating the predicted tower top acceleration based on the measured acceleration from each of the acceleration sensors.

The present disclosure relates to controlling an operation of a wind turbine. A first plurality of extreme load measures indicative of extreme loads experienced by at least part of the wind turbine during the first period of time are determined and a load probability characteristic is then determined based on a statistical analysis of the distribution of the first plurality of extreme load measures. A control strategy for controlling the operation of the wind turbine is then modified based at least in part on a comparison of the load probability characteristic and a design load limit and the wind turbine is then subsequently controlled in accordance with the modified control strategy for a second period of time.

The technology disclosed relates to a wind turbine and a measurement system comprising at least three measurement units, each arranged in substantially the same horizontal plane of a wind turbine tower and configured to measure their respective movements, and at least one tilt sensor or vertically oriented geophone arranged in substantially the same horizontal plane as the at least three measurement units and configured to determine the current tilt or inclination of a horizontal plane section determined by the mounting positions of the at least three measurement units. In particular, the measurement system comprising the at least three measurement units and the at least one tilt sensor or vertically oriented geophone is configured to continuously determine the current position and inclination of a horizontal plane section essentially determined by the mounting positions of the at least three measurement units based on the movement measurement data obtained by the at least three measurement units and the inclination of the horizontal plane section obtained by the at least one tilt sensor or vertically oriented geophone.

A method of determining tower top acceleration of a wind turbine is provided. The method includes receiving acceleration data from a plurality of acceleration sensors positioned in a nacelle of the wind turbine, including data indicative of a measured acceleration in a direction along at least one measurement axis of each respective acceleration sensor at a current time step. The method includes determining a predicted tower top acceleration of the wind turbine tower at the current time step, the predicted tower top acceleration being determined in dependence on a kinematic model of the wind turbine, and on a determined estimation of tower top acceleration at a previous time step. The method includes determining an estimated tower top acceleration of the wind turbine tower at the current time step by updating the predicted tower top acceleration based on the measured acceleration from each of the acceleration sensors.

A control system for a floating offshore wind turbine (FOWT). The FOWT includes a floating base, a tower, a nacelle, and rotor with blades that harvest energy from wind passing the FOWT. Without a rigid support, however, the FOWT is able to move. The controller uses generator speed and platform pitch position of the FOWT as inputs and manipulates blade pitch and torque resistance to achieve stability.