A system and method are provided for controlling a wind turbine to protect the wind turbine from anomalous operations. Accordingly, in response to receiving data indicative of an anomalous operational event of the wind turbine, the controller initiates an enhanced braking mode for the wind turbine. The enhanced braking mode is characterized by operating the generator at a torque setpoint that generates maximum available torque for a given set of operating conditions. Additionally, the torque setpoint is in excess of a nominal torque limit for the generator.

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.

Provided is a safety stop valve arrangement of a hydraulic blade pitch system of a wind turbine, including an accumulator arrangement connected over a hydraulic line to a piston of the hydraulic blade pitch system; a redundant set of safety valves arranged between the accumulator arrangement and the piston; a small-orifice restriction nozzle arranged to determine a first rate of hydraulic fluid flow in response to a safety stop input; at least one speed-select valves arranged; and at least one large-orifice restriction nozzle arranged to determine a second rale of hydraulic fluid flow in response to a positive rotor acceleration input, wherein the second rate of fluid flow is faster than the first rate of fluid flow. A safety stop assembly of a wind turbine with hydraulic blade pitch systems and a method of performing a safety stop sequence is also provided.

A braking assembly of a wind turbine includes a slewing ring bearing, at least one first drive mechanism having a first motor and a first drive pinion that rotationally engages the slewing ring bearing. The first motor is pre-tensioned in a first direction by a first amount of force. The braking assembly also includes at least one second drive mechanism having a second motor and a second drive pinion that rotationally engages the slewing ring bearing. The second motor is pre-tensioned in a second direction with a second amount of force. The first direction and the second direction are opposite of each other and the first amount of force are substantially equal to the second amount of force. Thus, the first and second amounts of force substantially cancel each other while also allowing dithering of at least one of the first and second motors, thereby preventing substantial rotational movement of the slewing ring bearing.

A wind turbine (1) comprising a tower (2), a nacelle (3) and a hub (7) is disclosed. The hub (7) comprises a blade canying structure (4) with one or more wind turbine blades (5) connected thereto. Each of the wind turbine blades (5) is connected to the blade canying structure (4) via a hinge (6) at a hinge position of the wind turbine blade (5), each wind turbine blade (5) thereby being arranged to perform pivot movements relative to the blade carrying structure (4) between a minimum pivot angle and a maximum pivot angle. The wind turbine (1) further comprises a stop mechanism arranged to move the wind turbine blades (5) to a safe pivot angle in the case of an emergency, the stop mechanism comprising a release mechanism (8, 12, 14) and at least one wire (9, 10) interconnecting the release mechanism (8, 12, 14) and each of the wind turbine blades (5). Activation of the release mechanism (8, 12, 14) causes an abrupt change in a pulling force applied to the wind turbine blades (5) by the wire(s) (9, 10), the change in pulling force causes the wind turbine blades (5) to move immediately to the safe pivot angle.

A wind power generation apparatus includes a rotating shaft, a wind power generation device assembled to the rotating shaft, and an acceleration restriction mechanism. The wind power generation device includes a drag blade fixed on the rotating shaft, an inner housing connected to an outer edge of the drag blade, and an outer housing sleeved around the inner housing. The acceleration restriction mechanism includes a plurality of swing arms pivotally connected to the inner housing and a metal ring fixed on the outer housing. A magnetic portion of each swing arm is movable relative to the inner housing from an initial position to an acceleration restriction position. When the magnetic portion of each swing arm is at the acceleration restriction position, the magnetic portion at least partially covers the metal ring, so that the metal ring generates an eddy current limiting a rotating acceleration of the drag blade.

The disclosed heat generating apparatus includes: a rotary shaft, a heat generator, a plurality of permanent magnets, a magnet holder, and a heat recovery system. The rotary shaft is rotatably supported by a non-rotative body. The heat generator is fixed to the body. The magnets are arrayed to face the heat generator with a gap such that magnetic pole arrangements of adjacent ones of the magnets are opposite to each other. The magnet holder holds the magnets and is fixed to the rotary shaft. The heat recovery system collects heat generated in the heat generator. A non-magnetic partition wall is provided in the gap between the heat generator and the magnets.

The disclosed heat generating apparatus includes: a rotary shaft, a heat generator, a plurality of permanent magnets, a magnet holder, and a heat recovery system. The rotary shaft is rotatably supported by a non-rotative body. The heat generator is fixed to the rotary shaft. The magnets are arrayed to face the heat generator with a gap such that magnetic pole arrangements of adjacent ones of the magnets are opposite to each other. The magnet holder holds the magnets and is fixed to the body. The heat recovery system collects heat generated in the heat generator.

A system and method are provided for controlling a wind turbine. Accordingly, a controller of the wind turbine detects a loss of traction of the slip coupling between a generator and a rotor of the drivetrain of the wind turbine. In response to detecting the loss of traction, the controller overrides a generator torque setpoint to alter a rotational speed of the generator. In response to the altered rotational speed of the generator, the traction of the slip coupling is increased. Increasing the traction of the slip coupling facilitates an application of generator torque to the drivetrain of the wind turbine.

A braking system for a turbine of a wind powered includes a hydraulic machine connected to a drive shaft of the turbine. A pressure regulating valve in the supply line of the hydraulic machine determines the pressure delivered to the supply line by the hydraulic machine. A control that is responsive to the speed of rotation of the drive shaft modulates the pressure regulating valve so as to increase pressure in the supply line as the rotational speed exceeds a predetermined speed to apply a braking force to the drive shaft.