Equivalent Thermal Conductivity Improvement of Stator Winding and Thermal Benefit for Air-Cooled Electrical Aviation Machine

Electrical machines with high power density are key enabling components of propulsion systems for flying cars. Air cooling system is widely utilized for electrical aviation machine for its compact and reliable composition. For air-cooled electrical machine, the equivalent thermal conductivity of stator winding is the main parameter in determining the thermal resistance inside the slot winding. To get a further understanding, the analytical evaluation method and improvement of the equivalent thermal conductivity of stator winding is studied. Furthermore, the influence of the improvement in equivalent thermal conductivity of stator winding on heat transfer path is investigated and thermal benefit and performance benefit are evaluated. The analysis shows that with the equivalent thermal conductivity of stator winding increases to 3 W/m·K, a 100 °C-temperature reduction can be achieved in the stator winding.