Bernd Cebulski
System Development E-Traction, IAV GmbH Chemnitz

Abstract

High efficiency and low cost are some of the challenges on the way to fully electrified car drivetrains to reach a high driving range and low battery cost. The biggest influence to a low loss electric machine is a high copper slot filling factor therefore the concept of the so called ‘hairpin winding’ is very popular among European carmakers. Despite its promising properties there are a lot of difficulties to face for the motor design engineer. Some of them like skin and proximity effect can lead to extensive losses in the high speed region deteriorating the overall car performance.
Starting from the primary design by using different approaches JMAG can be used in certain ways to handle most problems during the way to a robust, cost effective, mass production electric machine. Some new approaches of inverse design method will be discussed as well as some topics to find and optimize solutions for a good winding design that can be produced easily in high volumes and still keep a good compromise between cost and performance.