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China’s rare-earth stranglehold spurs rise in alternative motor technologies

19 March, 2013

China’s move to corner the market for rare-earth minerals (REMs) has prompted manufacturers of low-voltage industrial motors to adopt alternative technologies that reduce or eliminate the use of these materials, spurring new growth in the motors market, according to a forthcoming report from IMS Research, now part of IHS.

The report estimates that the global market for IE4 “super premium efficiency” LV motors will be worth $418.2m by the end of 2015, up 153% from $165.4m in 2012. Emerging lower-cost alternatives to traditional permanent magnet synchronous motors (PMSMs) that achieve IE4 levels of efficiency have added momentum to this niche market.

The graph (above) shows IHS’s predictions for global revenues from the sale of IE4 LV motors (bargraph, left-hand axis) and the market’s growth rate (line graph, right-hand axis).

IE4 motors based on conventional PMSM designs have relied heavily on rare-earth materials, such as neodymium and dysprosium, which are needed to produce the high-powered magnets that allow motor efficiencies above IE3 and Nema Premium levels.

But PMSM motor manufacturers have been hit hard in recent years by export caps on rare-earths imposed by China, the world’s leading producer and processor of these minerals, which caused neodymium magnet prices to soar in 2011. Some degree of stabilisation has returned since mid-2012, but prices still remain high and represent a cost that motor manufacturers have to pass on to their customers.

“Similar to the samarium cobalt (SmCo) magnet sourcing scarcity of the 1980s, which hastened the development and introduction of neodymium magnets to the marketplace, China’s tightening of its grip on REM exports has caused manufacturers to seek alternative IE4 technologies,” says IHS’s senior analyst for motors and mechanical power transmission, Mark Meza.

“Manufacturers have been very creative in dealing with magnet sourcing issues by producing drive technologies that reduce the number of neodymium magnets needed in a PMSM motor, or by producing IE4-class motors that use no magnets,” he adds.

For example, ABB’s synchronous reluctance motors and Nidec’s switched reluctance motors achieve IE4 levels of efficiency without using magnets, and offer viable, lower-cost alternatives to the traditional neodymium-based PM machines. Although reluctance technologies have been around for many years, they are attracting renewed interest because of their high efficiencies.

“When discussing the industrial IE4 motor market in the past, the landscape was mostly limited to neodymium-based PM motors, or motors with copper rotors,” Meza continues. “Now, several proprietary designs that use traditional ferrite magnet technology must be included in the discussion as well.”

For example, US-based NovaTorque has developed an electrically commutated PM IE4 motor that uses traditional ferrite magnets, while Hitachi Metals is developing an axial-flux motor using amorphous metal ribbons made of iron, silicon and boron, coupled with traditional ferrite magnet technology, to achieve an IE4 level of efficiency.

“There are always application-specific pros and cons when considering the most appropriate motor technology to use,” Meza remarks. “But in an energy-conscious world, having more alternatives, and at lower cost, will only help the industry.”

Most current IE4-class motors are limited to 1–5hp (0.74–3.7kW) power ratings. However, as industry acceptance increases with more affordable manufacturing cost structures, IHS expects higher power-rated IE4 motors to gain more traction in the marketplace.

IHS’s new report, The World Market for Low Voltage Motors – 2013 Edition, will focus on how, and to what degree, government-mandated motor efficiency regulations are affecting motor-efficiency transitions. It will also provide analyses of regional motor market growth, as well as covering applications. 

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