Method and system for controlling a wind turbine to reduce nacelle vibration

A controller of a wind turbine control system comprising a processor and a memory module, wherein the memory module comprises a set of program code instructions which when executed by the processor implement an operation of controlling a wind turbine comprising a tower supporting a rotor comprising a plurality of pitch-adjustable rotor blades, the operation comprising:

• obtaining a movement signal indicative of a lateral movement of the tower;
• determining a pitch modulation signal, based on the movement signal, for actuating a rotor blade to produce a desired horizontal force component to counteract the lateral movement of the tower;
• determining a radial force component acting on a rotor blade;
• determining a phase offset parameter for the rotor blade based on the radial force component;
• and
• transforming the pitch modulation signal into a pitch reference offset signal for the rotor blade based on the phase offset parameter.

A wind turbine, comprising:

• a tower;
• a rotor supported by the tower and comprising a plurality of pitch-adjustable rotor blades;
• and
• a controller comprising a processor and a memory module, wherein the memory module comprises a set of program code instructions which, when executed by the processor, configures the processor to perform an operation, comprising:
• obtaining a movement signal indicative of a lateral movement of the tower;
• determining a pitch modulation signal, based on the movement signal, for actuating a rotor blade to produce a desired horizontal force component to counteract the lateral movement of the tower;
• determining a radial force component acting on a rotor blade;
• determining a phase offset parameter for the rotor blade based on the radial force component;
• and
• transforming the pitch modulation signal into a pitch reference offset signal for the rotor blade based on the phase offset parameter.

A program product comprising a storage medium containing code which, when executed by one or more processors, configures the one or more processors to perform an operation, comprising:

• obtaining a movement signal indicative of a lateral movement of a tower supporting a rotor comprising a plurality of pitch-adjustable rotor blades;
• determining a pitch modulation signal, based on the movement signal, for actuating a rotor blade to produce a desired horizontal force component to counteract the lateral movement of the tower;
• determining a radial force component acting on a rotor blade;
• determining a phase offset parameter for the rotor blade based on the radial force component;
• and
• transforming the pitch modulation signal into a pitch reference offset signal for the rotor blade based on the phase offset parameter