Aluminum Hairpin Solution for Electrical Machines in E-Mobility Applications : Part II:Thermal and Cooling Aspects

Along with efficiency and performances, one of the main aspects of nowadays electric machines design is sustainability, especially when it comes to the transition period the automotive field is dealing with, and the focus placed on electrification. This paper aims at lowering the environmental load of the electric machines, replacing copper hairpin stator windings with aluminum ones. In the first part of the paper, electromagnetic aspects of the electrical machines design using aluminum hairpin were studied and a multi-objective optimization process was carried out taking into account design objectives in performance, cost, efficiency and sustainability. In this second part of the paper, the optimized design candidate resulted from the electromagnetic design optimization is evaluated from a thermal perspective, proposing potential layouts of the cooling system. The setup of the CFD and thermal models for the optimized design is addressed and conclusions on the thermal behavior of the proposed solution are made.