Wireless power transfer tested on Korean railway

Korean engineers have developed a new wireless power transfer technology for railways, harbor freight and airport.

The Korea Advanced Institute of Science and Technology (KAIST) and the Korea Railroad Research Institute (KRRI) today successfully tested it out on railroad tracks at Osong Station.

The technology supplies 60 kHz and 180 kW of power remotely to transport vehicles at a stable, constant rate, they say. It was developed originally as part of an electric vehicle system introduced by KAIST in 2011 known as the On-line Electric Vehicle (OLEV).

The first models, a bus and a tram, tap 20 kHz and 100 kW power at an 85 percent transmission efficiency rate, while keeping a 20cm air gap between the underbody of the vehicle and the road surface.


Today’s demonstration of the technology in a train shows that OLEV can be used successfully in larger-scale systems.

“We have greatly improved the OLEV technology from the early development stage by increasing its power transmission density by more than three times. The size and weight of the power pickup modules have been reduced as well,” says Professor Dong-Ho Cho of KAIST.

“We were able to cut down the production costs for major OLEV components, the power supply, and the pickup system, and in turn, OLEV is one step closer to being commercialized.”

KAIST and KRRI plan to apply the wireless power transfer technology to trams in May and high speed trains in September.