Cooling of Windings in Electric Machines via 3D Printed Heat Exchanger

Thermal Management of High-Power Density Electric Motors for Electrification of Aviation and Beyond

“…Contact resistance was eliminated by bonding the cooling channels to the windings with the thermally enhanced polymer with thermal conductivity of 2 W/m-K. Simulations predicted that with water supplied at room temperature, the peak temperatures of the stator and windings could be reduced by nearly 100 • C with a 5 kW heat load, when compared to the standard natural convection case, to approximately 133 • C. The inter-winding cooled motor, therefore, could operate at much higher power than it could with its original configuration while maintaining the integrity of its electrical insulators. Sixel et al [34] additively manufactured a polymer heat exchanger that facilitated flow channels between the coil windings (BW in Figure 7) and on the outside of the coil windings (OW in Figure 7). The flow channels were designed to be aluminum filled polycarbonate with thermal conductivity of 1 W/m-K by fused deposition modeling [34].…”

“…Sixel et al [34] additively manufactured a polymer heat exchanger that facilitated flow channels between the coil windings (BW in Figure 7) and on the outside of the coil windings (OW in Figure 7). The flow channels were designed to be aluminum filled polycarbonate with thermal conductivity of 1 W/m-K by fused deposition modeling [34]. The water-cooling channels occupied the OW and BW positions shown in Figure 7.…”

Additive Manufacturing in Construction of Electrical Machines – A Review

“…Fig. 4a) show a liquid cooled heat exchanger (HE) for direct heat evacuation from the winding body [13]. Here, HE is sharing the stator slot together with winding assembly.…”

“…Here, HE is sharing the stator slot together with winding assembly. To assess the HE concept, the authors evaluated a number of alternative plastics including: ABS, Al-PC, CF-Nylon and PLA, with Al-PC being the preferred choice here [13]. A 44% reduction in winding operating temperature as compared with no HE alternative stator/winding assembly has been reported.…”

“…Elements of thermal management systems for electrical machines, a) integrated liquid cooled HE (CAD of stator/winding together with HE and HE hardware) -University of Wisconsin-Madison[13], b) integrated aircooled HE/stator mechanical support (stator core pack and HE hardware) -Newcastle University, c) set of HG for enhanced heat transfer in electrical machines (hardware variants prior to final processing) -Newcastle University[15] Examples of rolling bearing cages fabricated using AM -Oak Ridge National Laboratory[16] …”