Kettering University in Flint has partnered with HELLA, a developer of electronic components for automotive parts with its North American headquarters in Plymouth Township, to develop an electric vehicle charger that would offer 97 percent efficiency.
“The design will make the charger ultra compact and light, which eventually will be a game changer for the (electric vehicle) charging industry,” says Kevin Bai, associate professor of electrical engineering at Kettering University. “By using gallium-nitride devices, the charger switching frequency also is significantly higher, nearly double the present charger.”
Bai is leading a research team at Kettering that is working on system design and testing. He says the charger has a two-stage design, unlike chargers now on the market that have a three-stage design. The three-stage design converts AC grid voltage to volts direct current or DC, then inverts the DC to high frequency AC to feed the transformer, and then finally converts AC back to DC to charge the battery. “The process offers 94 percent efficiency, while the two-stage design would improve efficiency by about 3 percent,” Bai says.
Bai says a prototype of the charger is expected to be completed by October, and several patents for the project have been applied for. Bai and his team have also developed a 24-kilowatt charger for Turkish automaker Derindere Motorlu Araclar and a 10-kilowatt charger for Magna E-car.