Efficient and Sustainable Production of Electrical Machines - Achieving a Higher slot Fill Factor Through an Innovative Forming Process Chain

With the increasing electrification of mobility and the associated growing demand for electric machines, issues of efficient and resource-saving production and operation are becoming ever more central. Therefore, it is important to optimize the design of components, materials and the assembly of electric machines. An example, described in the paper, shows how to increase the slot fill factor of a stator. By optimising the wire content in the slots, electric machines can be made smaller or, at the same size, operate more powerfully resp. efficiently. Various applicable production methods have different drawbacks such as low productivity, high energy and resource consumption, and restrictions for geometric design. Here, forming technology offers remedy in the utilization of material with simple tools and its suitability for mass production. This paper shows the analysed process chain developed at Fraunhofer IWU for the forming-based production of coils with trapezoidal cross-sectional geometry. The investigation results provide a more sustainable structure and an efficient process chain.