Abstract: An electric machine includes a flux-return yoke, a plurality of segmental permanent-magnet stator magnets mounted in the yoke with their outer peripheral surfaces engaging the inner peripheral surface of the flux-return yoke, and a wound rotor mounted for rotation in the space defined by the segmental stator magnets. Either the segmental stator magnets on their outer peripheral surfaces or else the flux-return yoke on its inner peripheral surface is provided with a structured surface portion adapted to properly position the stator magnets relative to the yoke. The structured surface portion has the form of a multitude of projections of identical height arranged in rows to form an array.