Rotating system for a wind turbine

Abstract

A rotating system (), such as a gear system or a bearing supporting system, for a wind turbine is disclosed. The rotating system () comprises a housing () arranged to substantially enclose the rotating system (), said housing () defining a lubricant drain () towards the exterior of the housing (), and a rotating part () accommodated in an interior part of the housing () in a manner which allows rotational movements of the rotating part () relative to the housing (), and in such a manner that lubricant can be contained between the housing () and the rotating part (). The housing () and/or the rotating part () is/are arranged to provide a pumping action forcing lubricant arranged in an interior part of the housing () towards the lubricant drain () during rotational movements of the rotating part () relative to the housing (). Excess lubricant is quickly and efficiently removed from the rotating part () and led to the lubricant drain (). Thereby a slip stream of lubricant is reduced. Accordingly, the friction occurring in the rotating system () is considerably reduced, and the efficiency of the rotating system () is therefore increased. Simultaneously, the outer dimensions of the rotating system () can be minimized because it is not necessary to generally increase the distance between the rotating part () and the housing () in order to avoid a lubricant slip stream. Furthermore, a method for operating such a rotating system () is disclosed.