Abstract: A wind turbine has a Lidar device to sense wind conditions upstream of the wind turbine. Signals from the wind turbine are processed to detect an extreme change in wind direction. The detection is performed by differentiating the rate of change of wind direction and filtering for a period of time. On detection of extreme change the system controller takes the necessary evasive action which may include shutting down the turbine, commencing an immediate yawing action, and de-rating the turbine until the yawing action is complete.

Abstract: A wind turbine power plant comprises a plurality of wind turbines, each having a rated output and under the control of a power plant controller. The power plant also has a rated output which may be over-rated in response to one or more electricity pricing data, power plant age and operator demand. This may comprise a schedule of output set point changes which effect seasonal or intraday changes in electricity prices or which reflect aging of the power plant. It may also reflect the price of electricity on spot or futures markets. Once the over-rating of the power plant has been set, the output may be increased by over-rating individual turbines or operating turbines at rated power if the sum of the rated outputs of the turbines exceeds or is equal to the new power plant output set point.

Abstract: The application describes a wind turbine having a control method and controller for performing predictive control of a wind turbine generator. Based on the measured instantaneous wind speed, it is known to provide control signals to a wind turbine in order to control the pitch of the wind turbine rotor blades and the speed of the generator. However, it is difficult using instantaneous wind speed measurements to achieve smooth control, due to finite response speeds of the associated electro-mechanical systems, as well as the constantly changing control system inputs. The predictive control system described in the application assumes a model of generator speed based on the values of the incident wind speed v(t) and the values of a control signal u(t) output to the wind turbine in a feed forward loop. Here, the control signal can be for one or more of controlling either the power setting of the generator, or the pitch angle of the rotor blades.

Abstract: Wind turbines of a wind power plant may be selectively over-rated by measuring the difference between the nominal and actual power plant outputs and deriving an over-rating request signal based on that difference which is sent to each turbine. The same value may be sent to each turbine. Alternatively, each turbine may be given its own over-rating amount based on an optimization of the turbine. Over-rating may also be used when external economic factors such as energy costs are sufficiently high to out-weigh any potential harmful effect of over-rating. The fatigue lifetime of turbines and their critical components may also be taken into account when deciding whether and to what extent to implement an over-rating command.

Abstract: A wind turbine has a Lidar device to sense wind conditions upstream of the wind turbine including wind speed, direction and turbulence. Signals from the Lidar are processed to detect an event which could give rise to low cycle fatigue loading on one or more components of the wind turbine. On detection the system controller takes the necessary evasive action depending on the nature and severity of the extreme condition detected. This may include a significant reduction in power generated through reduction in rotor speed or torque, complete shutdown of the generator and yawing of the nacelle and rotor in response to a change in wind direction.

Abstract: A wind turbine has a scanning Lidar arranged on the nacelle. The Lidar has a single scanning beam which scans about a substantially vertical axis to sense wind related data in a measurement volume a predetermined distance from the Lidar. Fast Fourier transforms of data from a plurality of points in the measurement volume are analysed to derive a peak velocity and a measure of variance. A controller receives the peak velocity and measure of variance as inputs and generates an output if the controller determines that the input data shows that the wind conditions are such that damage to the wind turbine is likely.

Abstract: A wind turbine has a Lidar (20) device to sense wind conditions upstream of the wind turbine. Signals from the wind turbine are processed to detect an extreme change in wind direction. The detection is performed by differentiating the rate of change of wind direction and filtering for a period of time. On detection of extreme change the system controller takes the necessary evasive action which may include shutting down the turbine, commencing an immediate yawing action, and de-rating the turbine until the yawing action is complete.

Abstract: Wind turbines of a wind power plant may be selectively over-rated by measuring the difference between the nominal and actual power plant outputs and deriving an over-rating request signal based on that difference which is sent to each turbine. The same value may be sent to each turbine. Alternatively, each turbine may be given its own over-rating amount based on an optimisation of the turbine. Over-rating may also be used when external economic factors such as energy costs are sufficiently high to out-weigh any potential harmful effect of over-rating. The fatigue lifetime of turbines and their critical components may also be taken into account when deciding whether and to what extent to implement an over-rating command.

Abstract: A wind turbine power plant comprises a plurality of wind turbines, each having a rated output and under the control of a power plant controller. The power plant also has a rated output which may be over-rated in response to one or more electricity pricing data, power plant age and operator demand. This may comprise a schedule of output set point changes which effect seasonal or intraday changes in electricity prices or which reflect aging of the power plant. It may also reflect the price of electricity on spot or futures markets. Once the over-rating of the power plant has been set, the output may be increased by over-rating individual turbines or operating turbines at rated power if the sum of the rated outputs of the turbines exceeds or is equal to the new power plant output set point.

Abstract: The application describes a wind turbine having a control method and controller for performing predictive control of a wind turbine generator. Based on the measured instantaneous wind speed, it is known to provide control signals to a wind turbine in order to control the pitch of the wind turbine rotor blades and the speed of the generator. However, it is difficult using instantaneous wind speed measurements to achieve smooth control, due to finite response speeds of the associated electro-mechanical systems, as well as the constantly changing control system inputs. The predictive control system described in the application assumes a model of generator speed based on the values of the incident wind speed v(t) and the values of a control signal u(t) output to the wind turbine in a feed forward loop. Here, the control signal can be for one or more of controlling either the power setting of the generator, or the pitch angle of the rotor blades.

Abstract: A wind turbine has a Lidar device to sense wind conditions upstream of the wind turbine including wind speed, direction and turbulence. Signals from the Lidar are processed to detect an event which could give rise to low cycle fatigue loading on one or more components of the wind turbine. On detection the system controller takes the necessary evasive action depending on the nature and severity of the extreme condition detected. This may include a significant reduction in power generated through reduction in rotor speed or torque, complete shutdown of the generator and yawing of the nacelle and rotor in response to a change in wind direction.

Abstract: A wind turbine has a Lidar device to sense wind conditions upstream of the wind turbine. Signals from the wind turbine are processed to detect an extreme event. On detection the system controller takes the necessary evasive action depending on the nature and severity of the extreme condition detected. This may include a significant reduction in power generated, complete shutdown of the generator and yawing of the nacelle and rotor to reduce loading on the rotor blades.