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Engineering consultancy Ricardo is developing a next-generation electric vehicle motor that avoids the use of expensive rare earth elements, making it much cheaper than existing products.
The prototype 85kW synchronous reluctance drive has been designed primarily for EV traction applications. It has emerged from the RapidSR (Rapid Design and Development of a Switched Reluctance Traction Motor), collaborative research and development project that includes carmaker Jaguar Land Rover.
Using a conventional distributed stator winding, the Ricardo synchronous reluctance electric machine uses low-cost materials, and simple manufacturing processes and construction. It has a rotor made from cut steel laminations, which direct and focus the flux across the air gap. By maximising this flux linkage between the stator and rotor, performance can be optimised within a tightly packaged design that is lightweight and free of rare earth elements.
Paul Rivera, managing director of the Ricardo hybrid and EV systems business, said: “As the market for electric vehicles grows, there is an imperative to explore alternatives to permanent magnet traction motors, which require the use of expensive and increasingly difficult-to-source rare earth elements. This prototype demonstrates what can be achieved by using the latest electric machine design processes.”
Since its launch in 2012, the RapidSR project has been researching the design of next-generation economic electric motors that avoid the rare earth elements typically used in permanent magnets. By developing effective CAE-led design processes as well as prototype designs, the team claims to have created a framework for the future design and manufacture of EV motors that offer the performance, compact packaging and light weight required for EV applications, but at a reduced cost compared to permanent magnet machines.
Ricardo’s partners in this research include project leader Cobham Technical Services – which is developing its multi-physics CAE design software, Opera, as part of the project – and JLR. The research is being co-funded by Innovate UK.
“By bringing together simulation technology with advanced electric machine design we have created a credible, next-generation EV motor concept that shows considerable promise,” said Dr Will Drury, Ricardo team leader for electric machines and power electronics.
“The prototype is now built and will be tested over the coming weeks to validate the positive results that it has shown in simulation, as a concept that provides a balance of performance, compact package, light weight and low cost.”