Researchers at Oak Ridge National Laboratory (ORNL) have achieved a significant milestone by demonstrating the first 270-kW wireless electric vehicle (EV) charging technology. This development follows their earlier record-setting achievement of a 100-kW wireless charger demonstrated in March.
In partnership with the Volkswagen Group, the team showcased the wireless power transfer of 270 kW on a Porsche Taycan EV. This compact high-power system addresses the challenges faced by light-duty passenger vehicles, such as space, weight, and volume constraints, which complicate the accommodation of large and heavy conventional wireless power transfer systems.
Innovative Compact Design
The current research focuses on developing wireless charging systems for light-duty cars that can achieve up to 11 kW of power with 92 percent efficiency. Industry standards currently support power levels up to 20 kW. ORNL has developed a lightweight system for powering the Porsche Taycan using polyphase electromagnetic coupling coils. These coils, slightly over 19 inches in diameter, deliver high power density in a compact form, inspired by the wireless charging technology used for small gadgets.
The system’s distinctive coil design and geometry enable the transmission of exceptionally high power levels through rotating magnetic fields created by the coil phase windings. This enhances power delivery, and the charging system is efficiently incorporated into the vehicle’s undercarriage. ORNL’s system achieves a 50 percent charge in just 10 minutes at over 95 percent efficiency, with a 4.75-inch gap between the coil and the ground.
Advanced Safety and Efficiency
Wireless power transmission technology from ORNL includes robust protection mechanisms against short-circuiting, overheating, and exceeding voltage and current restrictions. These systems can initiate shutdown operations in case of power outages or other unforeseen circumstances to ensure safe power transfer.
“We’re also working with Volkswagen on developing a polyphase system for residential charging applications and collaborating on the development of a lightweight enclosure design that will improve mechanical, electrical, thermal, and magnetic performance,” said Omer Onar, ORNL’s leader of the Vehicle Power Electronics group and lead researcher on the Porsche demonstration.
Future of EV Charging
For the past decade, ORNL researchers have been advancing wireless charging technology. In 2016, they successfully transferred 20 kilowatts to an SUV using their own inverter and coupling technology. By 2018, they reached 120 kW in lab tests with conventional coils. The recent 100- and 270-kW tests are the first applications of ORNL’s polyphase system on electric vehicles.
ORNL aims to extend the range and simplify the charging process to promote the usage of EVs, especially for light-duty passenger cars used for everyday commuting. “This achievement gets us one step further to the reality of a future where an electric vehicle can pull into a charging station and recharge in the same time it would take to walk into a store and grab a snack,” said Burak Ozpineci, ORNL’s corporate fellow and distinguished researcher who leads vehicle and mobility systems research.
In the near future, ORNL and Volkswagen plan to continue their collaboration to enhance the 270-kW charging prototype, aiming to make it a more affordable and scalable system. These trials support the Department of Energy’s objective of creating an extreme fast-charging system capable of charging electric vehicles in 15 minutes or fewer while supplying 250–300 kilowatts of power.
By Impact Lab
