When trains were getting faster than their coal-driven ancestors, train engineers turned to diesel fuel, and for a while, this was pretty good, especially with the addition of aerodynamic design and suspension design.
Eventually, though, instead of driving the wheels directly, electric motors were installed, which offered much more torque and speed. The diesel engines powered generators to directly power the motors. Instead of carrying a huge, and heavy, diesel engine, generator, and fuel, though, what if they could be eliminated?
The fastest trains in the world do not run on diesel anymore, but pure electricity. The electricity is fed through an overhead cable through a contact arm, the pantograph, and to the electric motors. These latest trains are lighter and more powerful than ever, but their speed is limited by the ability of the pantograph and overhead cable to withstand the passing over 200mph. But what if this limitation was removed as well?
The Korean Advanced Institute of Science and Technology, and Korea Railroad Research Institute is working on a wireless system to power trains. That would eliminate the need for physical contact from the power source to the train’s power system.
The On-Line Electric Vehicle [OLEV] prototype technology started out in a bus and a tram, both of which featured wireless charging up to 100kW at 85% efficiency without exceeding international standards for electromagnetic radiation.
The latest iteration of OLEV wireless technology has been tested with a battery-electric train and charging blocks under the tracks in Osong Station. Scaled up a little from the previous version, the new OLEV charges up to 180kW. For comparison, the Tesla Supercharger maxes out at 90kW with a physical connection. The train carrying the new wireless technology is indeed a battery-electric vehicle, but carries a battery only 1/5th the size of a traditional e-train.
Korean OLEV technology could revolutionize the high-speed trains of tomorrow. The wireless charging inductive coils of the OLEV system theoretically never wear out and can be placed under the tracks, safely out of the way. Power lines, utility poles, pantograph, and overhead cable can all be eliminated, saving space and maintenance costs, as well as enabling the trains to go faster.
