Filament-based additive manufacturing for material- and cost-efficient individual coils for electric drives (VCoil)
Project objective
Electric propulsion systems are a key component in making aviation more climate-friendly. For (hybrid) electric aircraft, low mass and high continuous power density are particularly crucial. However, conventional stator windings made from round or profiled wire make only limited use of the available slot space and typically achieve slot fill factors of around 50% to 60%. This results in limitations in terms of power density, installation space and material usage. VCoil is therefore investigating V-shaped individual coils, which are intended to enable a slot fill factor of up to 90 per cent through metal forming and additive manufacturing approaches. In addition, suitable insulation, direct conductor cooling, the processing of various conductor materials, and electrical, thermal and mechanical reliability must be demonstrated for use in the eAircraft.
HTW Dresden is responsible for the design of the electric machine and its experimental investigation. Based on the requirements analysis for the electric machine, a two-stage approach has been adopted, involving the design and experimental investigation of motor prototypes with V-shaped individual coils, and the transfer of the results into the multiphysical design of a laboratory prototype, direct drive for a small electric aircraft. Based on the results of the experimental investigation of the laboratory prototypes, the increase in power density achieved through the use of V-shaped moulded coils in combination with direct conductor cooling is to be validated, with the aim of achieving a continuous power density in the range of 7–8 kW/kg. Furthermore, conclusions are to be drawn from a comparison of machine variants with form coils produced using metal forming or additive manufacturing techniques, in order to enable the optimisation of manufacturing processes.
The R&D project thus makes a significant contribution to the sustainable manufacture of electric drive components, which can set new standards in the aviation industry through high material and energy efficiency as well as innovative manufacturing approaches.
Funding reference number
20M2434F
Funded by the Federal Ministry for Economic Affairs and Energy as part of the LuFo VII-1 aviation research programme
Duration
1 April 2026 – 31 March 2029
Project sponsor
German Aerospace Centre (DLR)