A method (200) for controlling a wind turbine (100) with a rotor having at least one rotor blade (17), the method comprising: measuring (210) a strain of the at least one rotor blade; changing (220) a pitch angle of the at least one rotor blade based at least partially on the measured strain of the at least one rotor blade; whereby the measurement of the strain of the at least one rotor blade measures at least one strain in the area of a blade root of the rotor blade (17).

A wind power generation device control system includes: a blade wind detecting device for detecting at least one of a wind direction or a wind speed on at least one blade of a wind power generation device; and a blade control device for controlling at least one of (i) a pitch angle of the at least one blade or (ii) a yaw angle of the wind power generation device, based on at least one of the wind direction or the wind speed detected by the blade wind detecting device.

The present disclosure is related to methods (400; 500; 600) configured for detecting the state of a wind turbine blade (22). The methods (400; 500; 600) comprising receiving (401; 501) load signals from a wind turbine blade (22), determining (402; 503) an energy of the load signal in a first and second frequency and comparing (403; 504) said energy to generate a flag signal if the energy in the first frequency is smaller than the energy in the second frequency. A control system (600) suitable to detect the state of a wind turbine blade (22) is also provided, as well as wind turbines (10) including such a control system (600).

A component has a first structural configuration and a second structural configuration. The component includes a sensor assembly including a plurality of interconnected structural members defining a plurality of load paths. A first structural member and a second structural member define a first load path when the component is in the first structural configuration. The first structural member and a third structural member define a second load path when the component is in the second structural configuration. The second load path is configured to bypass the second structural member. The sensor assembly is configured to detect a characteristic of the component that changes when the component switches between the first structural configuration and the second structural configuration.

A flanged shaft having a shaft part including a bearing seat for mounting an inner ring of a bearing arrangement and a flange part at a first side of the shaft. The flange part has an axially inner surface for axially retaining the inner ring. The flanged shaft is instrumented with one or more sensor units. Each unit having a measuring surface formed by an axially inner surface of at least one contact plate on which one or more sensors are provided for monitoring one or more operating parameters of the bearing arrangement. According to the invention, each of the one or more sensor units is arranged in a corresponding recess that extends through the flange part such that the measuring surface lies flush with or protrudes somewhat beyond the axially inner surface of the flange part.

A method of determining a distance between a rotor blade tip and a tower of a wind turbine includes: estimating the distance based on a strain measurement; measuring the distance; correcting an estimation procedure based on the estimated distance and the measured distance; and deriving a corrected distance based on the corrected estimation procedure.

A method for controlling wind turbine farm level loads by control strategy through site-specific topology effects. The method involves the steps of: providing wind velocity data from wind sensors mounted on the wind turbines, the velocity data comprising wind speed and wind direction; providing wind velocity data from one or more reference sensors, the velocity data comprising wind speed and wind direction; binning the wind data according to wind speed and wind direction; identifying wind turbines in which the velocity data deviates from the reference; and calculating modified loads acting on the wind turbines where the velocity data deviates from the reference; whereby the control strategy and/or maintenance activities are revised. A method for extending (or reducing) life of a wind turbine, altering performance (increased Annual Energy Production, AEP) (operational), or reducing cost through structural material reduction (design) is further disclosed. The approach can be used for scheduling maintenance for wind turbines in a wind farm.

The present invention relates to a method for optimizing the adjustment of the gating of a hydraulic turbine (1), this turbine (1) being provided with a set of wicket gates (2), these wicket gates (2) being able to move with a single, conjoined movement between a closing position in which they press against one another and an opening position in which they are apart from one another, by means of a control ring (4) that is kinematically connected to each one of these wicket gates (2), this control ring (4) being itself moved in rotation by at least one actuator (3), this actuator (3) comprising a device (31) for adjusting the travel of its rod (30), characterized by the fact that it comprises at least the following steps, said turbine (1) being previously stopped and dry and the rod (30) of said actuator (3) being provided with at least one strain gauge: 1/ Calculating the theoretical force to be applied to said actuator (3) in order to obtain watertight closure of said wicket gates (2); 2/ Measuring, via said strain gauge, the force applied to said actuator (3), the latter being inoperative; 3/ After bringing said actuator (3) online, moving its rod (30) until said wicket gates (2) adopt said closing position and measuring the corresponding force, referred to as the measured force; 4/ Comparing the measured force with the theoretical force calculated in step 1/.

Improvements Relating to Wind Turbines A wind turbine apparatus and a method of operating said wind turbine to maintain the load on the rotor blade below a predetermined threshold level is provided. The method comprises: measuring load at a root end of the rotor blade; measuring an acceleration at a location on the rotor blade outboard from the root end, the acceleration being caused by transient loads acting on the rotor blade; and controlling the wind turbine based upon the measured load and the measured acceleration to maintain the load on the rotor blade below a predetermined threshold level.

An offshore wind turbine support structure monitoring system and operating method are disclosed, comprising an offshore wind turbine, at least one state detection module, a data acquisition module, a data storage module, a network transmission module and at least one client. Thus, the maintenance of offshore wind turbines can be monitored directly and instantly to estimate the maintenance period, adjust the optimal operation and maintenance strategy, and save the cost.