A fluid-cooled wind turbine has at least one electric machine, in turn having a stator with a stator supporting structure and a plurality of active stator sectors supported by the stator supporting structure, and a rotor which rotates about an axis of rotation and has a rotor supporting structure and a plurality of active rotor sectors supported by the rotor supporting structure; and a cooling system having a cooling circuit extending partly along a plurality of through channels adjacent to at least the active rotor sectors or the active stator sectors.