Wind turbine flutter suppression method and device, control system and wind turbine

A control system for a wind turbine, comprising a controller and a pitch drive system;

• wherein
• the pitch drive system is configured to pitch blades of the wind turbine under control of the controller;
• and
• the controller is configured to:
• determine a nacelle-wind direction angle between a nacelle direction of a wind turbine and a wind direction;
• in response to the nacelle-wind direction angle being less than a first angle or greater than or equal to a second angle, control the pitch drive system to regulate pitch angles of blades of the wind turbine according to a rotor speed of the wind turbine to keep the rotor speed within a preset speed range until flutter of the wind turbine is suppressed;
• and
• in response to the nacelle-wind direction angle being greater than or equal to the first angle and less than the second angle, control the pitch drive system to perform a pitching operation on the blades of the wind turbine according to a pitch angle sequence in preset pitching rules until the flutter of the wind turbine is suppressed.