Delphi Automotive has equipped several test vehicles with its Wireless Charging System, a wireless energy transfer system featuring technology developed by WiTricity Corporation. (Earlier post.) Delphi is displaying the technology at this year’s IAA International Motor Show.
Engineers have installed the Delphi Wireless Charging System on multiple test vehicles, and have confirmed that system performance meets automotive market requirements, according to Randy Sumner, director, global hybrid vehicle development, Delphi Packard Electrical/Electronic Architecture.
WiTricity is commercializing an approach to “mid-range” wireless charging—distances from a centimeter to several meters. (Earlier post.) Developed by a team led by MIT Professor Marin Soljačić, the company’s technology is based on sharply resonant strong coupling, and is able to transfer power efficiently even when the distances between the power source and capture device are several times the size of the devices themselves. WiTricity’s technology is a non-radiative mode of energy transfer, relying instead on the magnetic near field.
Other wireless charging systems under development make use of conventional inductive charging. These systems work over a limited distance range, require precise accurate parking alignment and can be very large and heavy, making them impractical for widespread use on electric vehicles, Delphi says.
The Delphi Wireless Charging System offers more practical and flexible installation than traditional inductive systems because it uses highly resonant magnetic coupling, a modern technology that safely and efficiently transfers power over significantly larger distances and can adapt to natural misalignment often associated with vehicle positioning during parking.
The Delphi Wireless Charging System offers more practical and flexible installation than traditional inductive systems because it uses highly resonant magnetic coupling, a modern technology that safely and efficiently transfers power over significantly larger distances and can adapt to natural misalignment often associated with vehicle positioning during parking.—Randy Sumner
As a result, Delphi charging sources can be buried in pavement, are unaffected by environmental factors such as snow, ice or rain, can accommodate a wide range of vehicle shapes and sizes and accommodate differing ground clearances. The Delphi system is also more forgiving to vehicle parking positions on top of the charger without requiring any moving parts to accommodate. The system transfers energy using an oscillating magnetic field, which is intrinsically safe for humans and animals.
According to Sumner, the system will automatically transfer power to the electric vehicle’s battery pack at a rate of 3.3 kW—the same rate as most residential plug-in chargers—and is able to do so with the smallest and lightest modules possible. These components are important to minimizing overall vehicle weight and cost while maximizing the driving range of EVs.
We are excited by our testing and validation of the system and believe we have a valuable and unique wireless charging solution that offers the most potential for widespread use in the automotive market. With the support of automotive manufacturers, this technology can be integrated into the next generation of electric vehicles.—Randy Sumner
Wireless charging technology will need to co-exist with plug-in charging solutions, Sumner added, so that electric vehicle drivers have the ability to charge their vehicle when they are away from their wireless charging source.
Delphi also makes a Portable Electric Vehicle Charger that fits conveniently in the trunk of an electric vehicle. The user-friendly, UL-listed charging system plugs into any standard 120-volt outlet to enable safe electric vehicle battery charging at home or away. The charging unit can also be integrated into stationary charging applications.