Abstract:
A control system for a wind turbine is provided. A pitch-control unit establishes a pitch-reference signal representing a pitch to be set by the pitch-actuator system. A rotor-speed input receives a signal representing a speed of the rotor. A speed-reference input receives a speed-reference signal for the rotor speed. An inclination-signal input receives a signal representing a tower inclination. A pitch-reference output outputs the pitch reference signal. A modification unit is connected to the speed-reference input to receive the speed-reference signal and connected to the inclination-signal input to receive the inclination signal. The modification unit establishes a modification signal based on the inclination signal, to modify the speed-reference signal via the modification signal, and to output a modified-speed-reference signal. The pitch-control unit connected to the modification unit to receive the modified-speed-reference signal and establish the pitch-reference value at least based on the difference between the modified-speed-reference and the rotor-speed signals.
Abstract:
Method of operation of a variable speed wind turbine (11) comprising control means for a standard regulation tracking a power vs. generator speed curve (21) that also uses an alternative regulation for optimizing the energy production along determinate time periods Tb for compensating previous energy losses at a higher power Pb than the power determined by said standard regulation, said alternative regulation being based on a continuous calculation of the accumulated lost energy ALE as the energy lost with respect to the maximum allowed energy production according to the standard regulation and on a setting of said higher power Pb and a setting of the duration of said time periods Tb being compatible with wind turbine electrical or mechanical limitations. The invención also refers to a wind turbine controlled by said method.
Abstract:
The present invention provides a wind turbine generator and a blade pitch angle control method thereof in which an aerodynamic imbalance of a wind turbine rotor at the time of shutdown is further reduced, the maximum load of a wind turbine is further reduced, and the wind turbine generator can be reduced in weight and cost. The wind turbine generator includes a collective pitch angle controller 11 that produces a collective pitch angle demand that is common to blade pitch angles of wind turbine blades, an individual pitch angle producing unit 13 that produces an individual pitch angle demand inherent in each wind turbine blade, multipliers 21 to 23 that multiply the individual pitch angle demand by the individual pitch angle gain; an individual pitch angle gain producing unit 14, and adder 24 to 26 that add collective pitch angle demands to the output of the multipliers 21 to 23 and supply the same to pitch actuators 31 to 33 inherent in the wind turbine blades. When shutdown is performed, the individual pitch angle gain is adjusted such that an individual pitch angle gain is reduced gradually and reaches to zero by the individual pitch angle gain producing unit 14 after first set time.
Abstract:
A system and method for reducing rotor loads in a wind turbine that includes a brake and one or more rotor blades coupled to a rotor. Upon detection of a loss of counter torque and a blade-pitch failure in at least one rotor blade, a processor reduces a generator overspeed threshold value by a predetermined amount and determines a brake-release threshold value. The brake is applied to slow the rotor if the generator/rotor speed exceeds the reduced generator/rotor overspeed threshold value. In addition, the brake is applied to slow the rotor until the generator/rotor speed is below the brake-release threshold value. The rate of change of the pitch angle of the rotor blade may be varied as the blade moves toward feather in response to the detected blade-pitch failure.
Abstract:
The layout and configuration of wind turbines in a wind power plant includes identifying constraints of a power plant site and defining at least one region in the site for placement of a plurality of wind turbines. The wind state at the region in the site is determined. An actual wind condition at the various possible wind turbine locations within the site is determined by modeling the wind state with wake effects at the respective wind turbine locations. Individual wind turbine configuration and location within the region is then selected as a function of the actual wind conditions each of the individual wind turbine locations to optimize power output of the individual wind turbines. The selection of turbine configuration includes selection of a turbine hub height that minimizes wake loss of the individual wind turbines as a function of the actual wind conditions predicted for the turbine location.
Abstract:
The invention controls the network frequency via an active power reserve obtained by interacting in a coordinated manner with the speed regulation that acts on the power generated or on the pitch angle, to guarantee primary or secondary regulation across the whole range of wind speed.
Abstract:
A turbine (2) driven electric power production system (1),—said turbine (2) arranged for being driven by a fluid (3) having a fluid speed (v) varying in time,—said turbine (2) connected to a hydrostatic displacement pump (6) further connected to a hydrostatic displacement motor (8) as part of a closed loop hydrostatic transmission system (7),—said motor (8) arranged for driving an electrical generator (9) supplying AC power (10) at a frequency (fg) near a given desired frequency (fdes), characterized by a closed loop system arranged for controlling a volumetric displacement (13) of the hydrostatic motor (8), comprising—a fluid speed meter (11m) arranged for producing a speed signal (11s) representing a speed (v) of said fluid (3), and—a rotational speed meter (12m) arranged for providing a rotational speed signal (12s) representing a rotational speed measurement (ω) of said turbine (2), —a motor displacement control system (15) for continuously receiving said speed signal (11s) and said rotational speed signal (12s) and arranged for calculating a control signal (16), —a volumetric displacement control actuator (17) on said hydrostatic motor, arranged for receiving said control signal (16) for continuously adjusting a volumetric displacement (d) of said hydrostatic motor (8) for maintaining a set turbine tip speed ratio (tsrset) and thereby providing an improved power efficiency of the power production system (1) during fluctuations in said fluid speed (v).
Abstract:
A wind turbine includes a plurality of wind turbine blades attached to a rotor positioned atop a tower affixed to a tower foundation. At least one blade pitch sensor is configured to measure blade pitch angles for one or more of the wind turbine blades. A rotor/generator speed sensor is configured to measure the rotational speed of the wind turbine rotor, a corresponding wind turbine generator, or both. A wind turbine nacelle yaw sensor is configured to measure the nacelle yaw, while at least two tower-base bending sensors are configured without use of adhesives, cements or bonding agents to provide large-area measurement of tower deflection. A controller is configured to adjust the pitch angle of one or more of the wind turbine blades in response to the measured one or more blade pitch angles, the measured rotational speed, the measured nacelle yaw and measured tower longitudinal deflection.
Abstract:
The layout and configuration of wind turbines in a wind power plant includes identifying constraints of a power plant site and defining at least one region in the site for placement of a plurality of wind turbines. The wind state at the region in the site is determined. An actual wind condition at the various possible wind turbine locations within the site is determined by modeling the wind state with wake effects at the respective wind turbine locations, the wake effects resulting from cumulative placement of other wind turbines at various locations in the region. Individual wind turbine configuration and location within the region is then selected as a function of the actual wind conditions that each of the individual wind turbine locations to optimize power output of the individual wind turbines. The selection of turbine configuration includes selection of a turbine hub height that minimizes wake loss of the individual wind turbines as a function of the actual wind conditions predicted for the turbine location.
Abstract:
A control device is provided which is adapted for controlling at least one operational parameter of a wind turbine including a machine nacelle and a rotor having at least one rotor blade. The control device includes an input adapted for inputting a signal which is indicative of environmental data of the wind turbine, an evaluation unit adapted for generating at least one control signal on the basis of currently acquired environmental data and on the basis of previously acquired environmental data, and an output adapted to output the control signal adapted for adjusting the at least one operational parameter of the wind turbine.