Multiphysics topology optimization of aluminium and copper conductors for automotive electrical machines

Abstract

This paper proposes loss & thermally optimised copper and aluminium structures for automotive electrical machines. A first batch of multiphysics optimisation is performed parametrically for 6 different electrical conductor topologies. Then, a multiphysics -thermal and electromagnetic -hybrid parametric and topology optimisation coupled with Multi Objective Differential Evolution (MODE) and with an additional step of Local Search (LS) is proposed. The introduced Topology Optimisation (TO) algorithm is explained in detail and applied to optimise electrical conductor geometries of pure Cu and AlSi10Mg. After that, the manufacturing by Additive Manufacturing (AM) of the most promising model is presented. The produced topology is benchmarked against a well-known fully rectangular structure. The proposed topology optimised geometry has been found to improve conventionally manufactured electrical conductors at intermediate frequencies, around 600-800 Hz, and improves considerably at high frequencies, achieving a reduction in losses of 58% at 2000 Hz comparing to a conventional rectangular copper structure.