The University of Tennessee at Chattanooga Center for Energy, Transportation and the Environment (CETE) is leading an international team of researchers who are developing a more efficient way to power electric buses. With maximum efficiency and convenience, the Inductive Power Transfer, (IPT) will revolutionize this process.
“IPT is a contactless power transfer system that charges buses with electrical energy without any electrical or mechanical contact,” said Dr. J. Ronald Bailey, CETE director and Guerry professor. “Essentially, the system eliminates the effort required to plug and unplug battery charges to vehicles.”
This week, CETE is hosting researchers from the University of Kansas Transportation Research Institute (KUTRI); UniServices, Ltd., located at the University of Aukland, New Zealand; and the Wampleter Group, a leading international company for mobile energy solutions. Funding for this work is provided by the Federal Transit Administration.
As a proponent of alternative energy, innovation and science education, Congressman Zach Wamp supports the IPT.
“Technology and innovation are transforming the way people travel,” said Wamp. “The high-tech research of our local university and collaborating work from researchers around the world are helping lead the way in the development of more efficient and convenient ways to power our vehicles.”
Unlike a conventional transformer, IPT is a loosely coupled system. Each IPT system consists of a primary (stationary) side with a 70-kW track supply and two 30-kW primary coils imbedded in the street at the opportunity charge station (typically a bus stop at or near the end of the line). The secondary (vehicle) side consists of two 30-kW pickups and rectifiers, installed onboard the vehicle.
Power can be transferred across air gaps of several inches. Because it requires no physical contact, the system can operate in harsh environments. Power transfer is not affected by concrete, tar or other non-permeable materials.
“When an electric bus pulls into the charging station, the positioning system checks whether the bus is correctly positioned over the charging platform,” Bailey said. “If proper position is confirmed, a signal is sent to the Track Power Supply (TPS) to automatically begin the charging process. Persons, animals, cars, buses or trucks cannot cause activation of the charging station.”
For the Inductive Power Transfer system to be tested, a frame was needed to support the secondary coil while allowing for three dimensional movement. A Smart Cart team of engineering students from The University of Tennessee at Chattanooga were tasked with developing the frame as their senior engineering design project.
The Smart Cart team included Andrew Bonner, Matt Chatham-Tombs, William Dawson, Benjamin Gordon, Nathan Holland, Walter Hooper, Amir Malekzadeh, Michael Murphy and Eric Young.
“What’s really important is the experience our students are gaining. Their hands-on work begins to make sense of equations and theory,” Bailey said. They will go on to use this technology in their careers as they meet engineering challenges.”
Another student team converted a car that ran on gasoline or ethanol to hydrogen (see http://www.utc.edu/Academic/EngineeringProjects/HydrogenVehicle/ ) and a third student group has done research and design for the hydrogen fueling station (see http://www.utc.edu/Academic/EngineeringProjects/HydrogenFuelingStation/.
CETE researchers and students are also working with electric cars and hope to move into work with vehicles that use solar power.