A method of determining an offset angle to the wind direction measured from a wind vane of a wind turbine includes the steps of: defining a plurality of power bins representing an interval of power which can be produced by the wind turbine, calculating an efficiency of the wind turbine for a plurality of time slots, determining a power output of the wind turbine for the plurality of time slots, comparing the efficiency of the wind turbine in two different time slots, and updating a value of the one of the power bins representing the interval of power determined for one of the compared time slots. The value of the power bin is updated with the result of the highest efficiency or a value derived from the highest efficiency multiplied with a constant.

The invention relates to a method and a system for adjusting the torque of a mass and spinning wheel rotator in a wave power plant. The torque of a rotator rotating around a vertical shaft is compensated partially or completely with a compensating moment which is produced by an electric machine. Acceleration components (.sup.ACCx and .sup.ACCy) are measured for a given point of the wave power plant's floating body (1) in directions perpendicular to each other. A vector (V.sub.xy) with a magnitude formula (A) and a direction (a.sub.Acc) is established for said acceleration components, the direction or angular position (a) of a rotator (2) is monitored and its lag (α.sub.LAG) from the acceleration vector's direction (α.sub.Acc) is determined. The compensating moment is adjusted as dependent on a compensation factor (B) whose sub-factors are the magnitude of the body's acceleration vector (V.sub.xy) and the sine of the angle of lag (sin α.sub.LAG). This is supplemented with a compensation factor based on spinning wheel forces in a manner otherwise similar except that the acceleration must be replaced with a rotation speed (AV.sub.x-y) of the body's inclination, which is obtained from an inertial sensor 821). and the mass must be replaced with a gyro force which is dependent on the inertia and rotating speed of a spinning wheel.

The invention relates to a method for controlling a wind turbine in partial and full load. In order to avoid disadvantages of switching between partial and full load controllers, the wind turbine control system is configured so that both the partial and full load controller provides control action during partial and full load. For that purpose, the partial and full load controllers are configured with variable gains, wherein gain scheduling is performed so that the gain of partial load controller is larger than the gain of the full load controller during partial load and vice verso so that the gain of the full load controller is larger than the gain of the partial load controller during full load.

An optimal dispatching method and system for a wind power generation and energy storage combined system are provided. Uncertainty of a wind turbine output is characterized based on spatio-temporal coupling of the wind turbine output and an interval uncertainty set. Compared with a traditional symmetric interval uncertainty set, the uncertainty set that considers spatio-temporal effects effectively excludes some extreme scenarios with a very small probability of occurrence and reduces conservativeness of a model. A two-stage robust optimal dispatching model for the wind power generation and energy storage combined system is constructed, and a linearization technology and a nested column-and-constraint generation (C&CG) strategy are used to efficiently solve the model.

An optimal dispatching method and system for a wind power generation and energy storage combined system are provided. Uncertainty of a wind turbine output is characterized based on spatio-temporal coupling of the wind turbine output and an interval uncertainty set. Compared with a traditional symmetric interval uncertainty set, the uncertainty set that considers spatio-temporal effects effectively excludes some extreme scenarios with a very small probability of occurrence and reduces conservativeness of a model. A two-stage robust optimal dispatching model for the wind power generation and energy storage combined system is constructed, and a linearization technology and a nested column-and-constraint generation (C&CG) strategy are used to efficiently solve the model.

The invention provides a method for controlling a wind turbine, including predicting behaviour of one or more wind turbine components such as a wind turbine tower over a prediction horizon using a wind turbine model that describes dynamics of the one or more wind turbine components or states. The method includes determining behavioural constraints associated with operation of the wind turbine, wherein the behavioural constraints are based on operational parameters of the wind turbine such as operating conditions, e.g. wind speed. The method includes using the predicted behaviour of the one or more wind turbine components in a cost function, and optimising the cost function subject to the determined behavioural constraints to determine at least one control output, such as blade pitch control or generator speed control, for controlling operation of the wind turbine.

An aquifer storage and recovery system can include a pump, an electric motor coupled to the pump, a drive unit configured to control operation of the electric motor, and a controller. The controller can be configured to flow water into a well bore from a source reservoir through the pump such that the pump rotates in a reverse direction and drives the electric motor coupled to the pump in the reverse direction to operate as a generator, determine a power output of the electric motor, determine a difference between the power output of the electric motor and a power output set point, and operate the drive unit to control a rotational speed of the electric motor based at least in part on the difference between the power output of the electric motor and the power output set point.

The telescopic hydrokinetic turbine system is a device meant for lifting the burden of manufacturing, installing, and maintaining hydrokinetic systems in the water. The device attempts to overcome the issues faced by present day hydrokinetic systems. To accomplish this, the device includes a light weight and easy to carry and install design, a telescopic pillar to align itself with the tide direction or even to leave the body of water for maintenance. Electrical parts are not submerged but instead remain onshore in a small cabin or housing. Further, by adding the use of multiple diffusers, the water flowing into the turbine is made smoother and the overload of water is able to be evacuated and swiped by the fins. The diffusers increase the blades working capacity while homogenizing the water flow and avoiding the phenomena of vibrations and cavitation, thereby increasing efficiency.

A system and method are provided for controlling a wind turbine of a wind farm. Accordingly, a controller implements a first model to determine a modeled performance parameter for the first wind turbine. The modeled performance parameter is based, at least in part, on an operation of a designated grouping of wind turbines of the plurality of wind turbines, which is exclusive of the first wind turbine. The controller then determines a performance parameter differential for the first wind turbine at multiple sampling intervals. The performance parameter differential is indicative of a difference between the modeled performance parameter and a monitored performance parameter for the first wind turbine. A second model is implemented to determine a predicted performance parameter of the first wind turbine at each of a plurality of setpoint combinations based, at least in part, on the performance parameter differential the first wind turbine. A setpoint combination is then selected based on the predicted performance parameter and an operating state of the first wind turbine is changed based on the setpoint combination.

A power control method and apparatus for a wind power generator. The power control method comprises: predicting, according to historical wind resource data, wind resource data within a predetermined future time period (S10); estimating, according to the remaining design lifetime of a wind power generator, the maximum design lifetime allowed to be consumed within the predetermined future time period (S20); determining, according to the predicted wind resource data and the estimated maximum design lifetime, optimal output powers of the wind power generator in respective wind velocity ranges within the predetermined future time period (S30); and controlling operation of the wind power generator according to the determined optimal output powers of the wind power generator in the respective wind velocity ranges within the predetermined future time period (S40).