A controller for a wind turbine including a rotor and a nacelle arranged on a tower is provided, the tower having a fundamental frequency close to or below a rated rotational frequency of the rotor. The controller includes a rotor speed control module including a first linear time invariant control system adapted to generate a first pitch control signal based on a rotor speed error signal, a tower damping module including a second linear time invariant control system adapted to generate a second pitch control signal based on a nacelle acceleration signal, and an output module adapted to output a pitch control signal based on the first pitch control signal and the second pitch control signal. Furthermore, a wind turbine and a method of controlling a wind turbine is provided.

A controller for a wind turbine including a rotor and a nacelle arranged on a tower is provided, the tower having a fundamental frequency close to or below a rated rotational frequency of the rotor. The controller includes a rotor speed control module including a first linear time invariant control system adapted to generate a first pitch control signal based on a rotor speed error signal, a tower damping module including a second linear time invariant control system adapted to generate a second pitch control signal based on a nacelle acceleration signal, and an output module adapted to output a pitch control signal based on the first pitch control signal and the second pitch control signal. Furthermore, a wind turbine and a method of controlling a wind turbine is provided.

A rotor blade for a rotor having a vertical rotor shaft provides stream induced driving of the rotor in a direction of driving. The rotor blade includes streaming elements that are arranged successively and at a distance in the direction of driving, wherein each streaming element includes a front edge in the direction of driving and a rear edge in the direction of driving. The rear edge and the front edge are each formed such that, when streamed against by a wind component, it transmits a driving force to the rotor in the direction of driving. Furthermore, a rotor has a rotor blade and a system includes the rotor and an electric machine.

The devices and methods described herein are utilized to continuously track unpowered logistics platforms such as semi-trailers and intermodal shipping containers. In some examples, a tracking device harvests the kinetic energy of oscillatory movements of the shipping container to power the tracking device. In some instances, the shipping container is moving on a roadway, railway, or waterway. In other examples, a tracking device harvests the kinetic energy of airflow moving around the shipping container. In some instances, the airflow is caused by movement of the shipping container. In other instances, the airflow may be caused by ambient weather such that air is flowing around a stationary shipping container.

The devices and methods described herein are utilized to continuously track unpowered logistics platforms such as semi-trailers and intermodal shipping containers. In some examples, a tracking device harvests the kinetic energy of oscillatory movements of the shipping container to power the tracking device. In some instances, the shipping container is moving on a roadway, railway, or waterway. In other examples, a tracking device harvests the kinetic energy of airflow moving around the shipping container. In some instances, the airflow is caused by movement of the shipping container. In other instances, the airflow may be caused by ambient weather such that air is flowing around a stationary shipping container.

In a vertical rotor apparatus that rotates in response to a moving fluid, a shaft defines an axis of rotor rotation. Rotor blades are longitudinally aligned in parallel with the shaft and each rotor blade defines an axis of blade rotation. A sensor generates a signal when any of the rotor blades are within rotor azimuthal angles of blade stall regions. A controller generates blade pitch information for the blade stall regions and an actuator, which is mechanically coupled to each of the rotor blades, alters blade pitch about the axis of blade rotation in accordance with the blade pitch information.

In a vertical rotor apparatus that rotates in response to a moving fluid, a shaft defines an axis of rotor rotation. Rotor blades are longitudinally aligned in parallel with the shaft and each rotor blade defines an axis of blade rotation. A sensor generates a signal when any of the rotor blades are within rotor azimuthal angles of blade stall regions. A controller generates blade pitch information for the blade stall regions and an actuator, which is mechanically coupled to each of the rotor blades, alters blade pitch about the axis of blade rotation in accordance with the blade pitch information.

A vertical axis wind turbine rotor with a base having a rotational centre, a top surface, a top surface edge, and a plurality of top plates disposed radially around the rotational centre. The rotational centre defines an axis of rotation substantially orthogonal to the top surface. The top surface extends radially from the rotational centre to the top surface edge. Each of the top plates has a leading edge coupled to the base. Each top plate is passively transitionable between a first position above at a first height, and a second position above the top surface at second height. The rotor may also have a bottom surface with a plurality of bottom plates coupled thereto and disposed radially around the rotational centre. The bottom plates can be passively transitionable between a raised position and lowered position.

A vertical axis windmill comprises three or more frames rotatable in unison about a substantially vertical axis and a plurality of airfoils hingedly affixed to each frame. Each airfoil is able to swing away from its respective frame in a first direction from a closed position to an open position and not able to swing away from its respective frame in a second direction from the closed position.

A method for adaptive wind-driven outdoor all-surrounding information display is disclosed, the method including: 1) installing an outdoor information display apparatus, of which a support means cooperates with a wind rotating means to achieve wind power generation and rotational speed control of an information display means; 2) disposing a plurality of electronically controlled light-emitting display strips on the sails; 3) installing a plurality of working units of a motor/electric generation assembly; 4) installing a control system so that the dynamic trajectories of the rotating electronically controlled light-emitting display strips after they are lit are successively connected with each other thereby creating an all-surrounding and continuous visible graphic and textual image. Apparatuses and control systems implementing the above method are also provided.