A wind turbine is provided, including a hub, a blade shaft which is connected to the hub, a rotor blade which is connected to the blade shaft, a fixed bearing arrangement which is arranged at a blade end) of the blade shaft, and a floating bearing arrangement which is arranged at a hub end of the blade shaft, wherein the bearing arrangements enable a rotational movement of the rotor blade relative to the blade shaft. One advantage of the wind turbine including the bearing arrangements is that a better distribution of the loads is achieved. Further, the serviceability is better compared to bearings with rolling elements.

Provided is a method of controlling a pitch angle of at least one blade of a wind turbine by use of a hydraulic system, the hydraulic system including at least one reservoir configured to store a hydraulic fluid, and at least one pump configured to supply the hydraulic fluid from the reservoir to at least one accumulator, if a hydraulic fluid pressure in the accumulator falls below a lower threshold value and till the hydraulic fluid pressure in the accumulator exceeds an upper threshold value. The accumulator is configured to store the pressurized hydraulic fluid supplied by the pump and to supply the pressurized hydraulic fluid to at least one pitch control cylinder of the hydraulic system via at least one output valve of the hydraulic system. The pressurized hydraulic fluid in the pitch control cylinder drives at least one piston to change the pitch angle of the blade.

Method of controlling a wind turbine comprising a rotor comprising at least a first blade, the method comprising the step of varying an induction factor of the first blade over time by dynamically changing a pitch angle of the first blade over time between a first pitch angle and a second pitch angle while the first blade is rotating, wherein the first pitch angle is different from the second pitch angle, and wherein the dynamic change of the pitch angle over time is controlled such that the respective rotational position of the first blade at which the first blade is at the first pitch angle and the respective rotational positions of the first blade at which the first blade is at the second pitch angle are displaced in time and the varying induction factor of the blade occur at different angular positions in the rotor plane over time, such that a location and/or direction of a wake formed downstream of the wind turbine is dynamically changing with respect to the rotor of the wind turbine.

Provided is a method of determining a control setting of at least one wind turbine of a wind park, the method including: determining a free-stream wind turbulence and deriving the control setting based on the free-stream wind turbulence, wherein the control setting includes a yawing offset, and wherein the yawing offset is derived to be the smaller, the higher the free-stream wind turbulence is.

A method for detecting an electrical fault in the stator of an electric machine is provided, wherein the stator includes multiple groups of windings, wherein the windings of each group are assigned to a respective phase of the electric machine, including the steps of: determining a respective current firstly between a subgroup of one of the groups of windings and a distinct further subgroup of the same group of windings and/or secondly between a subgroup of one of the groups of windings and a neutral point, and/or thirdly between a neutral point and either a further neutral point or to a common neutral point connected to at least the neutral point and the further neutral point, evaluating a fault condition, wherein the fulfilment of the fault condition depends on the respective determined current, and outputting a fault signal to personal and/or a device when the fault condition is fulfilled.

A wind turbine control method includes: acquiring in real time a current wind direction of each upstream wind turbine in a wind farm; determining a current main wind direction to which the current wind direction of each upstream wind turbine belongs; determining, according to an association between the main wind directions of multiple upstream wind turbines and downstream wind turbines in the main wind directions, a downstream wind turbine associated with the current main wind direction of each upstream wind turbine; determining, according to an operating status and an operating parameter of the downstream wind turbine associated with the current main wind direction, a control instruction for each downstream wind turbine associated with the current main wind direction; and controlling, according to the control instruction, each downstream wind turbine associated with the current main wind direction. Also provided are a corresponding control device, a controller, and a control system.

A turbine, in particular for harvesting energy in flowing air or flowing water, is easily adaptable to different application conditions and facilitating a comparably high degree of efficiency. This is achieved in that the basic shape of the turbine is cylindrical and is provided with blades which are parallel to an axis of the turbine. The blades are pivotally arranged in joints on the outer circumference of at least one turbine wheel. The blades are substantially L-shaped. The longer limb of the blade is curved preferably in a manner corresponding to the radius of the turbine casing, and the shorter limb lies within the surface line of the turbine.

Provided is a method of detecting a leak in a hydraulic cylinder of a rotor blade pitch system of a wind turbine including a plurality of rotor blades, which method includes the steps of selecting one of the pitch systems to undergo a functionality test; actuating a fluid pump to move the pistons of the hydraulic cylinders of the pitch systems to their outermost positions; monitoring the hydraulic cylinder pressure levels of the non-selected pitch systems while performing the functionality test on the selected pitch system; and analyzing the monitored hydraulic cylinder pressure levels of the pitch systems to detect a drop in pressure in a pitch cylinder of a non-selected pitch system. A leak detection arrangement of a pitch-controlled wind turbine; and a pitch-controlled wind turbine are also provided.

Provided is a method for adapting an operating characteristic of a wind power installation. The installation has a rotor with rotor blades having adjustable blade angles and operable with a variable rotor rotational speed. To control the installation, use is made of an operating characteristic which describes a relationship between the rotor rotational speed and an operating variable. The operating characteristic has a first portion with a first rotational speed range and a second portion with a second rotational speed range. The first rotational speed range has lower rotational speeds than the second rotational speed range, and the operating characteristic is adapted such that values of the operating variable of the first portion are increased values of the variable of the second portion are changed toward higher rotational speeds, and an expected total number of revolutions of the rotor over a predetermined lifetime of the installation remains approximately the same.

A proactive method prevents vibrations in one or more rotor blades of a wind turbine when the wind turbine is in a standstill idling state with a rotor hub free to rotate. The method determines a minimum revolution rate of the rotor blades that prevents vibrations of the rotor blades and that the actual revolution rate of the rotor blades is below the minimum revolution rate. A wind parameter is detected and determined to be above a threshold limit. The method also detects if grid power is available for pitching the rotor blades. Based on the wind parameter, a controller determines a pitch angle for one or more of the rotor blades to increase rotation of the blades to at least the minimum revolution rate. The controller initiates pitching the rotor blades to increase the revolution rate of the rotor blades prior to vibrations being induced in the rotor blades.