METHOD AND SYSTEM FOR CONTROLLING ROTATIONAL SPEED RESONANT FREQUENCY CROSSING OF FLEXIBLE TOWER WIND TURBINE

A method and a system for controlling the rotational speed resonant frequency crossing of a flexible tower wind turbine. The method comprises: acquiring basic calculation data; processing acceleration ass of the left-right movement at the top of the tower; obtaining the root mean square of acceleration ass0 of the left-right movement at the top of the tower after a filter of an nth control period; and carrying out different running states according to a running flag bit A. The system comprises a tower modal online identification system (1), tower vibration sensors (2), and a speed measuring encoder (3), which are respectively connected to a system (4) for controlling the rotational speed resonant frequency crossing of a flexible tower wind turbine, the tower vibration sensors are uniformly installed on the tower from top to bottom. In the method and the system, adaptive control of a turbine rotational speed jump deviation value, a vibration amplitude, and a damping coefficient is achieved and the load of a flexible tower is reduced, thus ensuring the safety of a turbine; meanwhile, the wind turbine is enabled to operate in a maximum power point tracking mode for the majority of the time, evidently reducing power generation loss, and effectively improving the power generation efficiency of the wind turbine.