Drives and Controls Magazine
Motor 'delivers rare-earth performance without rare-earths'
Published:  21 January, 2015

The US motor manufacturer UQM Technologies has been granted a US patent for an electric and hybrid electric vehicle motor design that uses non-rare earth magnets and is claimed to deliver a similar performance to motors that use rare-earth magnets. The patent covers a “unique” rotor design and magnet geometry that enables the use of non-rare earth magnets and avoids the demagnetisation issues that would occur with these magnets if used in conventional motors. It also covers a motor manufacturing method.

Most electric and hybrid electric vehicles produced today use permanent magnet (PM) motors based on rare-earth magnet materials. Once development work on the new design is completed, it will allow UQM to choose whether or not to use rare-earth magnets, depending on future magnet costs.

“The patented technology that we’ve developed provides a viable option to existing rare-earth motor technology, limiting exposure for us and our customers to the price and political volatilities of rare-earth magnets,” says UQM president and CEO, Eric Ridenour. “We are now in the prototype stage and the first samples are meeting our objectives, providing us with the validation to move into the next phase of development.”

Implementation the newly patented technology is part of a $4m advanced research and development grant awarded to UQM by the US Department of Energy (DOE) to develop non-rare earth magnet motors for use in electric and hybrid vehicles.

UQM says that its non-rare-earth motor will deliver a similar performance to machines using rare-earth magnets

Colorado-based UQM develops and manufactures high-efficiency and high-power-density motors, generators and controllers for the truck, bus, automotive, marine, military and industrial markets.