The detecting a shadow is determined by a modeling of at least a portion of a wind turbine. First and second sensors are arranged relative to the model such that the first sensor detects a light and the second sensor detects a shadow during the conditions where the shadow would be produced.

A start control method for wind turbines (102), comprising: a master control determines whether its real-time wind speed reaches a preset start wind speed when a wind speed of at least one wind turbine (102) or anemometer tower in a wind farm reaches or exceeds the preset start wind speed; the master controller updates a corresponding number simulative start times when determining that its real-time wind speed reaches or exceeds the preset start wind speed, and starts the wind turbine (102) when the number of simulative start times reaches a preset count value. The present invention also relates to a master controller, a system, and a central controller for wind turbines (102).

A method for operating a wind farm having a plurality of wind turbines, each of which is assigned a minimum power limit (CMPL.sub.j), wherein a power setpoint value (SP.sub.P) for a power which is to be fed in is specified for the wind farm, in dependence on which power setpoint value (SP.sub.P) individual wind turbines are activated or shut down, wherein the activation or shut-down of one or more wind turbines in the wind farm takes place in dependence on the respectively assigned minimum power limits (CMPL.sub.j), wherein each wind turbine of the wind farm is assigned a current value for its minimum power limit, wherein the value takes into account variable operating conditions and/or ambient conditions of the respective wind turbine.

Embodiments herein describe operating a first wind turbine using an auxiliary control system when a high-voltage link coupling a wind park to a grid is not functioning. When using the auxiliary control system, the first wind turbine provides power to a local AC grid which can be used to power auxiliary system in a second wind turbine while the second wind turbine is shutdown. However, when the high-voltage link is functional, the first and second wind turbines provide power to the high-voltage link using a primary control system.

A method for initializing startup of a wind turbine includes measuring a first wind condition at the wind turbine at a first moment in time. The method also includes measuring a second wind condition at the wind turbine at a subsequent, second moment in time. Further, the method includes estimating an acceleration parameter of the wind turbine as a function of the first wind condition and the second wind condition. Moreover, the method includes comparing the acceleration parameter to a predetermined threshold. As such, the method includes initializing a first startup process for the wind turbine when the acceleration parameter is at or below a predetermined threshold. Further, the method includes initializing a second startup process for the wind turbine when the acceleration parameter exceeds a predetermined threshold, the second startup process being faster than the first startup process.

An embodiment provides controllers modules that allow for an energy generation module, such as a wind turbine, to be restarted locally and remotely. To restart the energy generation module remotely, care is taken to ensure the module is not in lock down mode. Further, the adding the ability to remotely restart the module does not alter the code or logic used to locally restart the module. Other embodiments are described herein.

Provided is a rotation device for rotating a wind turbine generator configured to be rotated by wind and to convert wind energy into electrical energy. The rotation device includes at least one rotary device configured to couple with an outer surface of the wind turbine generator, and a motor device for driving the rotary device such as to thereby rotate the wind turbine generator about a generator rotation axis. The wind turbine generator can be rotated in a state in which the wind turbine is not operating. This can be useful for training purposes in a training nacelle, for maintenance purposes when storing the nacelle or during assembly of the nacelle.

Provided is a method for starting a wind park including plural wind turbines connectable in a collector system connectable to a utility grid, the method including: starting at least one first wind turbine, each being equipped with an utility grid independent energy supply and a grid forming function, to produce electrical energy from wind energy, thereby utilizing the respective grid independent energy supply for starting; performing the grid forming function by the first wind turbine to achieve a reference voltage in the collector system; starting at least one second wind turbine and/or at least one third wind turbine to produce energy by conversion of wind energy, thereby utilizing energy provided in the collector system for starting.

A control method for a hydraulic control turning system of a generator rotor includes: establishing a length relationship table between multiple hydraulic cylinders of the hydraulic control turning system; selecting a reference hydraulic cylinder; acquiring current lengths of the multiple hydraulic cylinders when the multiple hydraulic cylinders are located at error correction positions; and adjusting lengths of the other hydraulic cylinders corresponding to a next driving stroke to conform with the length relationship table. With such an arrangement, the accumulated dimension error between the hydraulic cylinders may be dynamically corrected during the turning operation, thereby ensuring that the turning pins are accurately aligned with the pin holes in the generator, and the corresponding turning operation is performed after the generator set is locked. Based on this, a control device for a hydraulic control turning system of a generator rotor is further provided.

A method for controlling a wind turbine having rotor blades with an adjustable blade angle, comprising the steps operating the wind turbine in a partial load mode for wind velocities up to a nominal wind velocity, wherein in the partial load mode, a fixed partial load angle is provided for the blade angle, operating the wind turbine in a full load mode for wind velocities above the nominal wind velocity, wherein in the full load mode the blade angle is enlarged with increasing wind velocity and has values above the partial load angle, and wherein in the partial load mode, starting from a predetermined operating state, the blade angle is reduced as compared with the partial load angle.