An Eddy current tuned mass dampers (EC-TMD) is a type of TMD that is damped by an eddy current damping element. The Eddy current damping element is composed of permanent magnets and conductor plates. When the conductor plates move relative to the permanent magnets, the conductor plates cut the magnetic field lines of the permanent magnets to generate a force that hinders the relative movement. The eddy current immediately heats up in the conductor plates to dissipate energy, and the structural vibration mechanical energy is finally converted into thermal energy and consumed.

Vortex-induced vibration occurs when the frequency of wake disjunction in the back surface of the wind turbine tower coincides with the natural frequency of the tower. Vortex-induced vibration not only affects the erection progress of the WTG unit, but also threatens the safety of the tower, especially the second-order vortex-induced vibration of the flexible steel tower, and even leads to the toppling of the tower.

Wake field during vortex-induced vibration