Researchers at the Korea Advanced Institute of Science and Technology (KAIST) hope to move Korean mass transit away from overhead power wires and high-voltage rails. A system called On-line Electric Vehicles, or OLEV, is already being road-tested around the country.
OLEV uses inductive coupling, a technology that allows power cables embedded in roadways to transmit electricity to coils installed under the floor of electric vehicles. The cables can supply 180kW of stable, constant power at 60kHz to passing vehicles, which receive the power at about 100kW at 20kHz through a gap about eight inches wide, Txchnologist reports. The electricity is also used to charge an on-board battery that keeps the vehicle running even when it is not in close enough proximity to the power line.
In July 2013, an OLEV bus is scheduled to run on a regular, inner-city route in the city of Kumi, which consists of about 40 minutes of driving. This is the first vehicle with OLEV since its development to run on a road not specifically designed for it in a controlled environment.
There are also plans to install this technology on train tracks, Dong-Ho Cho, the director of the Center for Wireless Power Transfer Technology Business Development, wrote in a press release. He also said that compared to its early days, OLEV technology has improved by leaps and bounds and is feasible for public transportation, and for eventual commercialization.
It would eliminate the need for overhead wires in tram stations, and save fuel in buses. Trains running on OLEV power would also require smaller tunnels and need less maintenance to repair wear and tear, saving money on construction costs.
On the KAIST campus in Daejeon, the buses are already in use by students while the trams are used to shuttle passengers around in an amusement park in Seoul. OLEV was selected as one of the top ten emerging technologies of 2013 by the World Economic Forum. It was included with technologies such as 3D-printing, self-healing materials and energy efficient water purification.