Next-generation switched reluctance motor uses no rare earth elements

Ricardo RapidSR electric motor

Ricardo has developed a new prototype 85 kW synchronous reluctance motor designed for EV applications. Most EV motors use permanent magnets made from materials such as neodymium-iron-boron and samarium-cobalt. However, the rare earth elements in these compounds can be expensive and problematic to obtain.

Switched reluctance motors, which do not use permanent magnets, show great promise as a replacement technology. They are also simple and robust, and can offer good efficiency and high power density.

Ricardo RapidSR electric motor_250

“As the market for electric vehicles grows globally, 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,” said Ricardo Managing Director Paul Rivera. “The Ricardo prototype that we have announced today demonstrates what can be achieved by using the latest electric machine design processes in the creation of a high performing, compact, lightweight, and rare earth element free concept.”

Ricardo’s prototype has a rotor made from cut steel laminations, which are used to direct and focus the flux across the air gap. By maximizing this flux linkage between the stator and rotor, performance can be optimized in a tightly packaged and relatively lightweight design.

“The Ricardo prototype is now built and will be rigorously tested over the coming weeks in order to validate the extremely positive results that it has shown in simulation, as a concept that provides an exceptional balance of performance, compact package, light weight and low cost,” said Ricardo Team Leader Dr. Will Drury.


Source: RicardoGreen Car Congress