The invention describes an electrical coil arrangement (21) comprising at least one conductor turn (wi; wl, w2) with two conductor branches (23a, 23b), the first conductor branch (23a) of which is designed as a forward conductor with respect to the prespecified current flow direction and the second conductor branch (23b) of which is designed as a return conductor with respect to this current flow direction. In this case, the individual conductor branches (23a, 23b) are in the form of pressed litz wire conductors which are made stable by a cured filling material (40) and have a large number of electrically conductive individual wires (38), wherein each individual conductor branch (23a, 23b) is formed as a separate, prefabricated conductor segment (27) which is subsequently electrically conductively connected to one another, associated conductor branch (23b, 23a) in at least one end region (17). The invention further describes an electrical machine (1) comprising a coil arrangement (21) of this kind, and a method for producing a coil arrangement (21) of this kind.
he reduction of emission is a key goals for the aviation industry. One enabling technology to achieve this goal, could be the transition from conventional gas turbines to hybrid-electric drive trains. However, the requirements concerning weight and efficiency that come from applications like short range aircraft are significantly higher than what state-of-the-art technology can offer. A key technology that potentially allows to achieve the necessary power and volume densities for rotating electric machines is superconductivity. In this paper we present the concept of a high power density generator that matches the speed of typical airborne turbines in its power class. The design is based on studies that cover topology selection and further electromagnetic, HTS, thermal, structural and cryogenics aspects. All domains were analyzed by means of analytical sizing and 2D/3D FEA modeling. With the help of our digital twin that is a synthesis of these models, we can demonstrate for the first time that under realistic assumptions on material properties gravimetric power densities beyond 20 kW kg−1 can be achieved.