Dr. Kevin Bai

Kettering University researchers working on next generation charger for HELLA

“As an innovator, HELLA is very much a hands-on company. Engaging with the students and staff at Kettering University allows us to get a fresh perspective while sharing our knowledge of real world applications in technology.”

Researchers in Kettering University’s Advanced Power Electronics Lab (APEL) have become a go-to resource for global companies seeking innovations in electric vehicle (EV) charging technology.

The latest collaboration is with HELLA, a globally positioned company that develops and manufactures lighting technology and electronic products for the automotive industry. One such product is the Level-2 EV charger. Presently, level-2 EV chargers on the market have three-stage design -- converting AC grid voltage to 400 VDC, inverting this DC to high frequency AC to feed the transformer, and then rectifying AC to DC again to charge the battery. Assuming that each stage of that process leads to about a 2 percent loss of overall power, the overall wall-to-battery efficiency is 94 percent.

“As an innovator, HELLA is very much a hands-on company. Engaging with the students and staff at Kettering University allows us to get a fresh perspective while sharing our knowledge of real world applications in technology,” said Matt McAmmond, Advanced Engineering Manager at HELLA Corporate Center in Plymouth, Michigan.

A research team led by Dr. Kevin Bai, associate professor of Electrical Engineering at Kettering University, is working with HELLA to develop a next-generation charger that has a 2-stage design rather than 3-stage design, which would offer 97 percent efficiency, an improvement of 3 percent.

“By using the novel gallium-nitride devices, the charger switching frequency is also significantly higher, nearly double of the present charger,” Bai said. “The design will make the charger ultra compact and light, which eventually will be a game changer for the EV charging industry.”

The research team includes Bai, a research graduate and a research engineer working on the system design and test. A prototype of the charger is expected to be finished by October and several patents have already been applied for related to this project.

Bai and researchers in his lab have worked with numerous industry partners to develop charging technology, including development of a 24-kilowatt charger for Turkish automaker Derindere Motorlu Araclar (DMA) and development of a 10-kilowatt charger for Magna E-car.


Written By Patrick Hayes | Contact: Patrick Hayes - phayes@kettering.edu - (810) 762-9639