EM2 - HEaK

Efficient electric machines with high power density are needed for the development of low-emission vehicles. However, due to thermal limitations, conventional cooling concepts for traction drives often only allow continuous operation in the partial load range, which is why corresponding drives usually have to be dimensioned larger. One approach to significantly increasing power density is to use stators with internal cooling channels.

The integration of three-dimensional cooling channels is to be demonstrated by means of plastic-molded, additively manufactured tube structures. The innovative combination of the various manufacturing processes is intended to enable the simple production of complex cooling structures, for example to circumvent undercuts in the stator winding. As a result of the increased cooling capacity, the project aims to increase the continuous power density of a demonstrator machine by a factor of 2.

In the course of the project, the position of the internal cooling channels in the stator was optimized with the aid of thermal and electromagnetic analyses, and the influence of the materials used and the channel flow on thermal performance was systematically investigated. Concepts for the manufacture of the additively manufactured cooling channels and the hairpin winding used were developed for the construction of the demonstrator machine, and the injection molding process was simulated. The prototype intended for validation is currently under construction and will finally be measured on a performance test bench.