Manufacturing analysis of a molded electric motor design with internal stator cooling

In this study, the overmolding process of an electric motor with internal stator cooling technology utilizing composite materials shall be investigated. A comprehensive concept has been developed for a high-performance continuous power traction motor featuring distributed hairpin winding. However, the limited design space, stator design with multiple materials as well as increased machine dimensions for a high-power electric motor create challenges in optimizing electromagnetic, thermal, and manufacturing designs. The technical feasibility in large scale production processes is particularly crucial for the industrialization of the presented concept. In this context, three test specimens with increasing complexity were designed and produced using transfer molding. This approach allows for the analysis of various aspects, including the effects of the production process and demolding, long-term durability, and the identification of design limitations of the concept.