Methods (200) for reducing vibrations in one or more rotor blades (120) of a wind turbine (160), when the wind turbine is in standstill conditions are provided. The method comprises measuring (201) one or more deformation parameters indicative of deformation of one or more blades (120), determining (202), at a dedicated controller (190) for an auxiliary drive system (20, 107), a vibration of one or more of the blades (120) based on the deformation parameters, wherein the dedicated controller (190) for the auxiliary drive system is separate from the wind turbine controller (180), and generating (203), at the dedicated controller (190), an output signal to operate the auxiliary drive system to reduce the vibration. Also disclosed are wind turbines (160) which comprise a dedicated controller (190) configured to determine a vibration and generating an output signal to reduce the vibration, when the wind turbine is in standstill conditions.

A yaw system of a wind turbine having contingency autonomous control capabilities includes a plurality of yaw system components configured to change an angle of a nacelle of the wind turbine relative to an incoming wind direction. The plurality of yaw system components includes an auxiliary power supply comprising a brake power control device, a braking unit coupled to the brake power control device, at least two energy storage devices coupled to the braking unit, a plurality of yaw drive mechanisms communicatively coupled to the auxiliary power supply via a communication link, and a controller configured to implement a protective control strategy for the yaw system in response to one of the yaw system components experiencing a failure. Each of the yaw drive mechanisms includes a yaw power control device.

There is provided a mobile control unit for a wind turbine which has a plurality of components. The mobile control unit has a supply module having a main control unit and at least one control module coupled to the supply module for controlling the components of the wind turbine. The main control unit serves for controlling the components of the wind turbine by means of the control modules connected to the supply module.

Provided is a wind turbine with an auxiliary power supply. The wind turbine includes a generator, a main converter and a transformer. The generator is connected with the main converter. The main converter is connected with the transformer. The transformer is connected with an electrical grid. Thus electrical power with a varying frequency, being produced by the generator, is converted into electrical power with a defined frequency by the main converter and the electrical power with the defined frequency is transformed and provided to the grid by the transformer while the transformation is done in accordance to grid code requirements. An auxiliary power supply, providing auxiliary power, is connected via an auxiliary converter with the transformer, thus the auxiliary power supply is decoupled from the transformer and from the grid by the auxiliary converter.

The present disclosure is directed to a system for controlling a yaw drive of a wind turbine when a native yaw drive control system is non-operational. The system includes an external sensor configured to detect a parameter indicative of a wind condition experienced by the wind turbine. The system also includes an external controller communicatively coupled to the external sensor. The external controller is configured to control the yaw drive based on measurement signals received from the external sensor. The external sensor and the external controller are electrically isolated from the native yaw drive control system.

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 system and a method of performing a safety stop sequence is also provided.

A method for testing capacity of at least one energy storage device of a pitch drive mechanism to drive a first rotor blade of a wind turbine connected to a power grid includes defining a rotor position range for implementing a first test procedure for the energy storage device(s). Further, the method includes monitoring a rotor position of the first rotor blade. When the rotor position of the first rotor blade enters the rotor position range, the method includes initiating the first test procedure. The first test procedure includes pitching the first rotor blade via the energy storage device(s), measuring at least one operating condition of the energy storage device(s) during pitching, and determining a capacity of the energy storage device(s) to drive the first rotor blade based on the operating condition(s) thereof.

A system for generating power includes a supervisory control and data acquisition (SCADA) system that provides control commands to a plurality of turbine controllers to cause a windfarm to output power at a level within power parameters in a setpoint. Each turbine controller is installed at a corresponding wind turbine of a plurality of wind turbines in the windfarm. The system also includes a backup system comprising a programmable logic controller (PLC). The PLC receives turbine state information from the SCADA system that characterizes an operational state of each of the plurality of wind turbines in the windfarm and detects that the SCADA system is offline. The PLC also selectively provides start and stop commands to a plurality of terminal interface units (TIUs) to cause the windfarm to output power at a level within the power parameters identified in the setpoint in response to the detecting.

A system for generating power includes a supervisory control and data acquisition (SCADA) system that provides control commands to a plurality of turbine controllers to cause a windfarm to output power at a level within power parameters in a setpoint. Each turbine controller is installed at a corresponding wind turbine of a plurality of wind turbines in the windfarm. The system also includes a backup system comprising a programmable logic controller (PLC). The PLC receives turbine state information from the SCADA system that characterizes an operational state of each of the plurality of wind turbines in the windfarm and detects that the SCADA system is offline. The PLC also selectively provides start and stop commands to a plurality of terminal interface units (TIUs) to cause the windfarm to output power at a level within the power parameters identified in the setpoint in response to the detecting.

A fan failure backup apparatus includes a first fan module and a second fan module. When a second control unit of the second fan module realizes that the first fan module is failed through a first control unit of the first fan module, and the second control unit realizes that the second fan module is not failed, the second control unit controls the second fan module to additionally enhance a pressure-flow characteristic of a second fan unit of the second fan module.