Disclosed is a state determination device for a liquid pumping apparatus including: a casing that forms a reservoir space for storing liquid flowed thereto; a feed valve that introduces working gas into the reservoir space; an exhaust valve that releases the working gas from the reservoir space; and a valve operating mechanism having a float arranged in the reservoir space, and performing a pumping stroke in which the liquid is pumped from the reservoir space under a pressure of the working gas by opening the feed valve and closing the exhaust valve when the float moves up to a predetermined high level, and an inflow stroke in which the liquid flows into the reservoir space and the working gas is released from the reservoir space by closing the feed valve and opening the exhaust valve when the float moves down to a predetermined low level. The state determination device includes a pressure sensor that detects a pressure of the reservoir space, and a determination unit that determines whether the liquid pumping apparatus is in an operating state of performing the pumping stroke or the inflow stroke based on the pressure detected by the pressure sensor.

Systems, methods, and kits for reducing structural vibrations on wind turbine blades are provided. The actual dynamic structural conditions of a wind turbine blade can be used as a feedback mechanism. A flow control device and a sensor can be installed on a wind turbine blade, and a closed loop control system in operable communication with the flow control device and the sensor can be used to provide closed loop control.

A method for controlling loads of a wind turbine includes receiving sensor signals from one or more sensors being indicative of a movement of a nacelle of the wind turbine from a reference point. More particularly, the movement corresponds, at least, to a tilt and/or a displacement of the wind turbine tower and/or nacelle. The method also includes generating a deflection profile of the tower along its overall length from a bottom end to a top end thereof based on the sensor signals. Further, the method includes determining at least one of a thrust or a tower load of the wind turbine from the deflection profile. In addition, the method includes implementing a control action for the wind turbine based on the thrust and/or the tower load.

Devices and methods for mechanism-based feedback controller employed in a wind powered power system are provided. A controller can include a vector control-based voltage source converter with feedback control circuitry. The feedback control circuitry is configured to modulate either a power order or a dc-link voltage order to control coupling between voltage and power. The controller can be connected to a wind-based turbine generator of a wind farm and regulate power deployed to a power grid.

A method for controlling loads of a wind turbine includes receiving sensor signals from one or more sensors being indicative of a movement of a nacelle of the wind turbine from a reference point. More particularly, the movement corresponds, at least, to a tilt and/or a displacement of the wind turbine tower and/or nacelle. The method also includes generating a deflection profile of the tower along its overall length from a bottom end to a top end thereof based on the sensor signals. Further, the method includes determining at least one of a thrust or a tower load of the wind turbine from the deflection profile. In addition, the method includes implementing a control action for the wind turbine based on the thrust and/or the tower load.

Devices and methods for mechanism-based feedback controller employed in a wind powered power system are provided. A controller can include a vector control-based voltage source converter with feedback control circuitry. The feedback control circuitry is configured to modulate either a power order or a dc-link voltage order to control coupling between voltage and power. The controller can be connected to a wind-based turbine generator of a wind farm and regulate power deployed to a power grid.

Provided is a method for damping a side-side oscillation of a tower of a wind turbine having a generator connected to a converter, the method including: measuring an acceleration value of the tower; determining, based on the acceleration value, at least one frequency value of at least one tower oscillation mode, including a second tower oscillation mode; controlling the converter of the wind turbine based at least on the acceleration value and the frequency value.

Provided is a control arrangement for controlling an electrical machine, including: a fundamental current controller, at least one harmonic flux controller related to a harmonic of an electrical frequency of the electrical machine, a summation system for adding voltage commands to obtain a summed voltage command based on which the electrical machine.

An embodiment provides controllers modules that allow for an energy generation module, such as a wind turbine, to be restarted locally and remotely. To restart the energy generation module remotely, care is taken to ensure the module is not in lock down mode. Further, the adding the ability to remotely restart the module does not alter the code or logic used to locally restart the module. Other embodiments are described herein.

A method for damping an oscillation of a tower of a wind turbine is disclosed, wherein a pitch angle of each of the one or more rotor blades is individually adjustable, the method comprising damping the oscillation of the tower by pitching each rotor blade individually according to tower damping pitch control signals, wherein each tower damping pitch control signal comprises a first periodic component, where a first frequency of the first periodic component corresponds to a frequency difference between a tower frequency of the oscillation of the tower and a rotor frequency of a rotation of the rotor, and where a second periodic component has been reduced or removed. A second frequency of the second periodic component corresponds to a frequency sum of the tower frequency and the rotor frequency.