Experimental Parameter Analysis for the Induction based thermal Demagnetization of PM Rotors from Electric Traction Drives

In the context of decarbonization, electromobility is currently undergoing a strong global expansion, whereby up to 75 million vehicles could be electrically powered by 2035. Ensuring the supply of necessary raw materials is crucial for this development. Electric vehicles require critical raw materials not only for batteries but also for the traction drives. Due to their advantageous properties, permanent magnet (PM) motors containing rare earth (RE) magnets are mostly applied. The required RE elements are considered as critical raw materials due to their highly vulnerable supply. In parallel, their primary production has a high ecological footprint. In this context, recovery of RE magnets from traction drives is a key to ensure a resilient and sustainable supply chain. Corresponding extraction processes are currently the subject of research, whereby demagnetization is always obligatory. For this purpose, a process based on inductive heating of complete rotors is proposed and systematically analyzed.