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: A maintenance apparatus is provided for use with a wind turbine that has a tower, a hub supported by the tower, and a plurality of blades extending outwardly from the hub. The maintenance apparatus has a mounting element that is configured to be secured to the tower and to be selectively movable along the length thereof. A robotic arm is coupled to the mounting element, and a blade-engaging device is coupled to the robotic arm and is configured to engage one of the blades to effect a maintenance task thereon.

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 with a rotor comprising one or more rotor blades and a hub, the hub being attached to a nacelle, a yaw system for rotating the rotor to orient it in a wind direction, and one or more line of sight detectors for detecting a component of wind velocity. The one or more detectors are mounted such that they rotate under the action of the yaw system. A control system is coupled to the one or more detectors and is arranged to compare the detected wind velocity component with a wind velocity value and control the yaw system in response to the comparison. The nacelle can be rotated under control of the control system until the yaw error is substantially zero.

Abstract: A wind park comprises a plurality of wind turbines with a least one wind turbine downstream of at least one upstream turbine. The downstream turbine includes a Lidar or other device for sensing characteristics of the wake produced by the upstream turbine and for providing an output to a turbine or wind park controller indicative of the measured wake. The controller controls parameters of the downstream turbine an possibly adjacent turbines in accordance with the wake indicative signals. The control may include overrating the downstream turbine if the wake indicative signal indicates that there is a low risk of fatigue damage to components of the downstream turbine.

Abstract: Embodiments of the invention provide methods, systems, and apparatus for determining a property of wind approaching a wind turbine. A light detection and ranging equipment may be used to determine a property of the wind at a plurality of locations ahead of a turbine. A wind flow model may be used to determine the property of wind expected at the rotor of the wind turbine based on the readings of the light detection and ranging device.

Abstract: Embodiments of the invention provide methods, systems, and apparatus for determining a property of wind approaching a wind turbine. A light detection and ranging equipment may emit pulsed radiation into oncoming wind to detect properties of the wind at a plurality of predefined locations. A property of the wind approaching the wind turbine may be determined based on the property of wind measured at at least two predefined locations.

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.

Abstract: Method, system, and computer program product for collecting sensor readings from a component of a wind turbine. The system includes a data collection system coupled in communication with a sensor. The data collection unit includes a processor configured to direct the sensor readings from the sensor to a buffer for temporary storage and to identify a triggering event by comparing the sensor readings received from the sensor with a reference value. In response to the identification of the triggering event, the sensor readings are transferred from the buffer to the mass storage device and stored in a non-volatile form by the mass storage device.

Abstract: A maintenance apparatus is provided for use with a wind turbine that has a tower, a hub supported by the tower, and a plurality of blades extending outwardly from the hub. The maintenance apparatus has a mounting element that is configured to be secured to the tower and to be selectively movable along the length thereof. A robotic arm is coupled to the mounting element, and a blade-engaging device is coupled to the robotic arm and is configured to engage one of the blades to effect a maintenance task thereon.

Abstract: A method of controlling combustion in an homogenous charge compression ignition engine through indirect mechanisms. The method utilizes a predictive model so that combustion can be controlled over a wide range of operating conditions while maintaining optimum operation with respect to efficiency and emissions. The methods include an adaptive aspect, which allows the predictive model to be updated if deemed necessary. Furthermore, the methods include a model with a plurality of control modes. A control mode can be chosen to optimize the engine for one of a plurality of output characteristics, including response time, efficiency, or emissions characteristics.

Abstract: There is described a method for controlling a system, for example a Diesel engine, that is subject to transient changes of target outputs. The target outputs specify outputs required from the system. “Steady state” information is used to give optimum inputs for the system when the target outputs are substantially constant. A model of the system is used to predict the outputs of the system in response to candidate new values for the inputs of the system. The method combines the steady state information with the predicted response of the system to determine inputs to the system which will cause the system outputs to match the target outputs as closely as possible. For each candidate (in one embodiment), the method calculates the difference between the steady state inputs and a candidate, and the difference between the target outputs and the predicted outputs that would result from the adoption of that candidate, to determine an optimum candidate which is then used to update the inputs to the system.

Abstract: A method of controlling combustion in an homogenous charge compression ignition engine through indirect mechanisms. The method utilizes a predictive model so that combustion can be controlled over a wide range of operating conditions while maintaining optimum operation with respect to efficiency and emissions. The methods include an adaptive aspect, which allows the predictive model to be updated if deemed necessary. Furthermore, the methods include a model with a plurality of control modes. A control mode can be chosen to optimize the engine for one of a plurality of output characteristics, including response time, efficiency, or emissions characteristics.