Energy-saving EV motors now in overdrive

Non-auto industry players advancing current technologies to improve performance

Electric cars at a parking lot of an automobile factory in China's Hebei Province © Reuters
TOKYO -- As the global market for electric vehicles continues to grow, companies in Japan are racing to improve the drive motors in EVs. So far, they are looking like winners. 

Lithium-ion batteries typically get most of the attention from the standpoint of squeezing out longer driving distances. But developers are starting to look more closely at drive motors, owing to their role in overall vehicle performance.

Since EVs have only about half to one-tenth the number of engine parts compared to gasoline-powered vehicles, there are fewer avenues to increase performance, hence the renewed interest.

Japan is a leader in developing motors for air conditioners, home appliances, factories and other applications. This has opened the field for companies outside the auto industry to jump on the EV bandwagon through research and development of drive motors.

Companies not associated with the auto industry are now digging deep into their technologies of everything electric -- from air conditioners to industrial motors -- to devise more energy-efficient motors, and are making new partners along the way.

Industry-education collaborations

Daikin Industries, a multinational air conditioning manufacturer, has joined forces with Osaka Prefecture University in an attempt to drastically reduce electricity loss in drive motors, while Mitsubishi Electric and Kanazawa Institute of Technology have developed a new motor that rotates efficiently regardless of driving speed.

 
A new drive motor that was developed jointly by Kanazawa Institute of Technology and Mitsubishi Electric.
Professor Shigeo Morimoto and associate professor Yukinori Inoue at OPU are working with Daikin engineers in their quest for a more efficient motor. The team employs innovations such as a two-layer array of permanent magnets to drive their motor, and is also experimenting with new materials to increase magnetic fields and electric currents.

The team came up with a 30cm prototype that convinced them of the possibility of reducing electricity loss by 40% compared with drive motors in domestically manufactured hybrid vehicles. The motor would use new materials for magnetic steel sheets and permanent magnets found in iron cores and other components.

They will continue testing in the hope of eventually producing a commercially viable motor.