Miba lecture at Vienna Motor Symposium: electric motors with bar windings

The latest research and developments in the diverse field of vehicle drives and the latest trends in automotive engineering were presented at the 39th International Vienna Motor Symposium and discussed by more than 1,000 experts, including top managers of the automotive industry, development engineers and scientists from all over the world. Mateo Primorac from Miba eMobility Innovation Lab gave a lecture on "High efficient electric motors with bar windings for serial production".

Electric motors with bar windings are one of the most important innovation directions in the electrification of vehicles. Compared to round wire windings, in most cases bar windings (Hair-Pin) show a higher copper fill factor in the slot and a better thermal connection. The result is advantages in efficiency and power density. Other advantages can arise when straight bars (I-pin) are used. The thermal and electrical efficiency in particular can be improved. The thermal efficiency is optimized by using a highly flexible winding head cooling for efficient head dissipation behavior. The electrical efficiency is optimized by using parallel pins to lower existing AC resistance effects at higher frequencies. Additionally, more flexible variations of performance and torque classes are possible by using uneven pins. Furthermore, cost and quality benefits are present when applying the simpler production process of i-pins. The undesirable and complex process steps of the hair-pin forming, the insertion into the lamination core and the cutting are not necessary. This influences the product cost for high-volume serial production.