Abstract: A nacelle assembly for a wind turbine is connected to a wind turbine tower through a yaw system and includes a front region coupled to a rotor having a rotor hub and at least one rotor blade. The nacelle assembly includes a nacelle having a cover structure to house wind turbine components and an add-on wind flow deflector system that is coupled to an outside of the cover structure. The wind flow deflector system guides wind flowing to the nacelle for reducing a drag of the nacelle when a wind direction is misaligned with respect to the longitudinal wind direction in a yaw system failure event.

Abstract: In a first aspect, a nacelle assembly for a wind turbine is provided. The nacelle assembly is connected to a wind turbine tower through a yaw system and comprises a front region coupled to a rotor comprising a rotor hub and at least one rotor blade. The nacelle assembly further comprises a nacelle having a cover structure to house wind turbine components and an add-on wind flow deflector system. The add-on wind flow deflector system is coupled to an outside of the cover structure to guide wind flowing to the nacelle for reducing a drag of the nacelle when a wind direction is misaligned with respect to the longitudinal wind direction in a yaw system failure event.