Abstract:
A method for controlling an individually pitched wind turbine during shutdown is disclosed, the wind turbine comprising at least three wind turbine blades (1a, 1b, 1c). In response to a shutdown command for stopping operation of the wind turbine, a blade parameter of each of the wind turbine blades (1a, 1b, 1c), e.g. pitch angle, bending moment or blade acceleration, is determined. The blade parameters of the wind turbine blades (1a, 1b, 1c) are compared, and a shutdown strategy for the wind turbine is selected from a group of two or more predefined shutdown strategies, based on the comparing step. Finally, the wind turbine blades (1a, 1b, 1c) are moved towards a feathered position in accordance with the selected shutdown strategy.
Abstract:
The present invention relates to control of wind turbines where a fatigue load measure is taken into account. Control of a wind turbine is described where a control trajectory is calculated based on a fatigue load measure, the fatigue load measure being determined from a predicted operational trajectory. In embodiments the predicted operational trajectories are calculated by using a model predictive control (MPC) routine, and the fatigue load measure includes a rainflow count algorithm.
Abstract:
The present invention relates tocontrol of wind turbines based on predicted operational trajectories. A control system for a wind turbineis described wherea main controller calculating one or more predicted operational trajectories and a safety controller validates at least one of the one or more predicted operational trajectories. The control system controls the wind turbine with the predicted control trajectory if the validation is valid, and controls the wind turbine with a safe-mode control trajectory if the validation is invalid. In an embodiment, the main controller is implemented as a receding horizon controller, e.g. in the form of a model predictive controller (MPC).
Abstract:
A shutdown controller for a wind turbine comprises, to improve the estimation of a state of the wind turbine, at least two sensors being adapted to provide sensor data significant for different mechanical states in the wind turbine. The controller can provide an estimated state of the wind turbine based on the sensor data from the at least two sensors and compare the state of the wind turbine with a predefined detection limit to provide a shutdown signal if the estimated state is outside the detection limit.
Abstract:
The invention provides a safety system for a wind turbine comprising a tower with a nacelle, and a rotor with blades and a connected drive train. The safety system comprises at least one load sensing system for providing a load signal significant for a load on the tower or rotor, and an electronic system which based on the load signal brings the wind turbine to a safe condition.