Remanufacturing a Synchronous Reluctance Machine with Aluminum Winding: An Open Benchmark Problem for FEM Analysis

Abstract

The European Union’s increasing focus on sustainable and eco-friendly product design has resulted in significant pressure on original equipment manufacturers to adopt more environmentally conscious practices. As a result, the remanufacturing of end-of-life electric machines is expected to become a promising industrial segment. Identifying the missing parameters of these types of machines will play an essential role in creating feasible and reliable redesigns and remanufacturing processes. A few case studies related to this problem have been published in the literature; however, some novel, openly accessible benchmark problems can facilitate the research and function as a basis for comparing and validating novel numerical methods. This paper presents the identification process of an experimental synchronous machine. It outlines methodologies for identifying material properties, winding schemes, and other critical parameters for the finite element analysis and modelling of electric machines with incomplete information. The machine in question is intended for remanufacturing, with the plan to replace its faulty winding with an aluminium-based alternative. It also serves as an open benchmark problem for researchers, designers, and practitioners.

Circular Economy Aspects of Permanent Magnet Synchronous Reluctance Machine Design for Electric Vehicle Applications: A Review

“…Due to the environmental issues related to copper [51,96,134], the easier recycling and lower mass density of aluminium [135], the significantly lower price of it [136], its abundance [137], and higher flexibility in manufacturing [138,139], the use of aluminium has re-emerged as a possible winding solution over copper in the case of electric machines. Even though aluminium has ∼65% higher resistivity (2.83 µΩcm), ∼47% lower thermal conductivity (210 W/m • C), and ∼41% higher thermal expansion coefficient (19.63 mm/mm) considering pure metals [140,141].…”

“…The amount of eddy current loss is inversely proportional to the conductive material's specific resistance (σ). Aluminium has 64% higher specific resistance than copper, so it is expected to have lower eddy current losses [141]. Comparing the AC losses of copper and aluminium conductors that have been designed for the same winding concludes that the difference in the AC/DC loss ratio, which exponentially increases after the break-even point at around 300 Hz, is in favour of aluminium winding [150].…”