A wind generator includes a revolving platform rotationally connected with a base; a tower body, where a bottom end of the tower body is connected to the revolving platform, a top end of the tower body is fixedly provided with a generator room, and a plurality of blades are rotationally connected to the generator room through a wheel hub; and the tower body is provided with at least one windward side in the circumferential direction of the tower body, and a bending stiffness of the windward side is not less than that of the remaining sides of the tower body; and a power source, where the power source is started when airflow is to the sides rather than the windward side to enable the airflow to flow to the windward side while the windward direction of the blades coincides with the airflow. A wind generator group is further provided.

Control of a multi-rotor wind turbine system. A local controller is arranged for each wind turbine module and implementing a local model predictive control (MPC) routine. A central controller is arranged to determine a set of operational constraints of the wind turbine modules. Based on a current operational state of the wind turbine module and the set of operational constraints, one or more predicted operational trajectories are calculated and used for controlling the wind turbine module.

New down-wind horizontal axis turbine (DWHAT) systems or apparatus and methods for making and using same, wherein the DWHAT systems or apparatus include a base structure, a tower assembly or a derrick assembly anchored to the base structure, a drive assembly, a sail assembly, and a generator assembly, wherein the sails of the sail assembly are configured to catch wind downwind of the apparatuses or systems and wherein the drive assembly converts horizontal rotation of the horizontal shaft into vertical rotation of the vertical shaft that turns the generator generating electrical power that is transmitted to a power grid.

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.

A method for operating a wind turbine with hinged wind turbine blades is disclosed. The wind turbine comprises an adjustable biasing mechanism arranged to apply an adjustable biasing force to each wind turbine blade which biases the wind turbine blade towards a position defining a minimum pivot angle or towards a position defining maximum pivot angle. A biasing force is selected for each wind turbine blade and the selected biasing force is applied to the respective wind turbine blades. The wind turbine is operated while monitoring rotor unbalance of the wind turbine. In the case that the rotor unbalance exceeds a first threshold value at least one of the wind turbine blades is selected, and the biasing force applied to the selected wind turbine blade(s) is adjusted.

A method of retrofitting a wind turbine (10) having a wind turbine tower (12) and a first energy generating unit (14) includes rotating at least a portion of the wind turbine tower (12). The wind turbine tower (12) is secured to a foundation (16) and has a first position on the foundation (16). The method includes rotating at least a portion of the wind turbine tower (12) from the first position to a second position. In the second position, the portion experiences less stress when the wind turbine (10) is operated in the same prevailing wind. The wind turbine tower (12) may have at least two sections (12a, 12b, 12c) and wherein rotating includes rotating one section relative to another section. One section may be secured to a foundation (16). In that case, rotating may or may not include rotating the section secured to the foundation (16). Rotating the tower may occur after the first energy generating unit (14) is removed from the tower and may include rotating the wind turbine tower by an angle from 90°±15° relative to the first position.

Enabling control of wind turbines is provided. The method comprises receiving power production signals from wind turbines comprising a wind farm and estimating wake travel times from upstream wind turbines to downstream turbines. Correlations of the power production signals are calculated among all pairs of wind turbines in the wind farm. Wind turbines with a power production correlation above a specified threshold at an expected time are considered to have wake interaction. A probability density function of northing directions is calculated for the wind turbine pairs with wake interaction. A determination is made whether the probability density function has a dominant direction. Responsive to the probability density function having a dominant direction, the wind turbine pairs with wake interaction are identified as turbine clusters. A control strategy is applied to each turbine cluster as an operational unit to optimize power production of the wind farm.

Systems and methods of autonomous farm-level control and optimization of wind turbines are provided. Exemplary embodiments comprise a site controller running on a site server. The site controller collects and analyzes yaw control data of a plurality of wind turbines and wind direction data relating to the plurality of wind turbines. The site server determines collective wind direction across an area occupied by the plurality of wind turbines and sends yaw control signals including desired nacelle yaw position instructions to the plurality of wind turbines. The site controller performs wake modeling analysis and determines desired nacelle positions of one or more of the plurality of wind turbines. The desired nacelle yaw position instructions systematically correct static yaw misalignment for all of the plurality of wind turbines. Embodiments of the disclosure provide means to perform whole site or partial site level controls of the yaw controllers of a utility scale wind turbine farm. The overall effect of the coordinated yaw control of wind turbines across the whole or partial site is intended to keep the wake loss of the wind turbines from the upstream wind turbines to the minimum and to maximize the production of turbines that are not waking other turbines.

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.

There is provided a method of avoiding edgewise vibrations during a non-operational period of a wind turbine. The method comprises defining a non-operational period for a wind turbine arranged at a specific site, determining expected wind conditions at the specific site during the non-operational period and defining a plurality of potential yaw orientations for the wind turbine. The method further comprises determining the relative probability of edgewise vibrations occurring during the non-operational period for each potential yaw orientation based upon the expected wind conditions during the non-operational period, determining one or more preferred yaw orientations, which are the yaw orientations in which the probability of edgewise vibrations occurring is lowest, and arranging the wind turbine in one of the preferred yaw orientations during the non-operational period.