A system and method are provided for controlling a wind turbine in response to a blade liberation event. Accordingly, estimated response signatures for the wind turbine are determined. Sensor data indicative of at least two actual response signatures of components of the wind turbine to a rotor loading are collected. The actual response signatures are compared to the estimated response signatures. The two or more actual response signatures meeting or exceeding the estimated response signatures is indicative of a blade liberation event. In response to detecting the blade liberation event, a rapid shutdown control logic is initiated to decelerate the rotor at a rate which exceeds a nominal deceleration rate of the rotor.

A system and method are provided for controlling a wind turbine in response to a blade liberation event. Accordingly, estimated response signatures for the wind turbine are determined. Sensor data indicative of at least two actual response signatures of components of the wind turbine to a rotor loading are collected. The actual response signatures are compared to the estimated response signatures. The two or more actual response signatures meeting or exceeding the estimated response signatures is indicative of a blade liberation event. In response to detecting the blade liberation event, a rapid shutdown control logic is initiated to decelerate the rotor at a rate which exceeds a nominal deceleration rate of the rotor.

The present invention relates to a floating wind energy harvesting apparatus for offshore installation, comprising an elongated wind turbine body extending along a longitudinal wind turbine body axis; at least one blade attached to the wind turbine body for converting wind energy to rotation of the wind turbine body around the longitudinal wind turbine body axis; an energy converter coupled to the wind turbine body for converting the rotation of the wind turbine body to electrical energy; and a braking arrangement for controllably reducing a rotational speed of the wind turbine body. The braking arrangement comprises an inlet; an outlet; a water transporting arrangement coupled to the wind turbine body to transport water from the inlet to the outlet in response to rotation of the wind turbine body; and an access control arrangement for controllably preventing water from passing through the water transporting arrangement.

A drivetrain system, braking method and braking system for a wind turbine is disclosed having a generator; a gearbox; a generator shaft and gearbox output shaft coupled between the generator and the gearbox, each shaft extending along a common longitudinal axis; a brake system having at least two brake disks with a first brake disk and a second brake disk, the first and second brake disks mounted concentric with the longitudinal axis; and a plurality of disk brake calipers having a first brake caliper and a second brake caliper, the first and second brake calipers mounted concentric with the longitudinal axis and engaged with the first and second brake disks, respectively.

The present invention relates to a floating wind energy harvesting apparatus for offshore installation, comprising an elongated wind turbine body extending along a longitudinal wind turbine body axis; at least one blade attached to the wind turbine body for converting wind energy to rotation of the wind turbine body around the longitudinal wind turbine body axis; an energy converter coupled to the wind turbine body for converting the rotation of the wind turbine body to electrical energy; and a braking arrangement for controllably reducing a rotational speed of the wind turbine body. The braking arrangement comprises an inlet; an outlet; a water transporting arrangement coupled to the wind turbine body to transport water from the inlet to the outlet in response to rotation of the wind turbine body; and an access control arrangement for controllably preventing water from passing through the water transporting arrangement.

An object of the present invention is to provide a natural energy extraction apparatus comprising a vertical rotating shaft and a float for supporting the vertical rotating shaft, wherein the internal structure of the float is simpler, the float and a mooring apparatus are more compact, and production cost is lower than in the conventional natural energy extraction apparatus. A natural energy extraction apparatus comprises a first float forming a swingable vertical rotating shaft, a second float moored to surround the first float, and a power transmission device attached to the second float to convert rotational kinetic energy of the first float to driving torque for driven equipment, and the natural energy extraction apparatus is installed on a body of water.

A control device for a yaw system of a wind turbine, of the type having a supporting structure and a machine support rotatably mounted on the supporting structure for rotation about a yaw axis, includes at least one adjusting device connected between the supporting structure and the machine support of the wind turbine. The at least one adjusting device includes a drivetrain having a drive element and a gear mechanism and at least one yaw brake operable to selectively rotationally fix the machine support on the supporting structure. The yaw brake engages between the drive element and the gear mechanism of the drive train of the adjusting device.

A hydraulic system for a rotor brake of a wind turbine, where the hydraulic system has a pressure chamber, a manually operable pump device and a connection for connection to the rotor brake. The manually operable pump device is connected to the pressure chamber and the connection. The manually operable pump device comprises a coupling section for actuation. The coupling section is configured to be connected to an external device.