Thermal analysis of the electrical axle drive from project HeAD – High performance electrical Austrian Drivetrain

Abstract

The highly increasing demand for environmentally friendly electrically powered vehicles requires electric drive units that are characterized by high efficiency, compact size, high performance and sustainability. The consortium by TU Wien, Zoerkler Gears, Thien eDrives, Power I.D. and e.battery systems has defined the HeAD project funded by the FFG with the goal of developing a highly integrated electric drive axle with a high speed electric machine for passenger cars operated by an innovative control. A high integration level of the electrical axle with a compact size and a high power density leads to a strong mutual influence of specific components, especially considering the loss and cooling characteristics. Therefore, one focus is set to a holistic thermal consideration of the electric axle in order to ensure high availability with demand-oriented cooling under all operating conditions and enabling an optimal operation close to the thermal limits of the materials and components used, like permanent magnets, motor windings, oil, etc. In this work, results from simulations and experimental tests of the built prototype are presented to show insights and further optimization potential of the HeAD e-axle.