The 12-volt automobile electrical system has reached the end of the road, according to Mary Gustanski, Delphi Automotive’s vice president of engineering and program management.
In an interview with Automotive News, Gustanski explained developing electrical architectures will have to support:
• All the components for autonomous driving — cameras, radar, lidar sensors, computers, etc.
• A greater array of drivetrain components, such as the oil and water pumps, that will switch from mechanical to electrical power.
• An assortment of hybrid-drive parts that will propel the car under electric power.
• More computing power that will improve vehicles’ connectivity, not just to the Internet, but to other vehicles and buildings, traffic signals and other structures in the environment.
Delphi estimates that adding 48-volt capability could cost around $1,200 per vehicle.
Gustanski believes hybridization and the electrification of energy-hungry components will be essential for most automakers to meet tighter fuel economy standards.
U.S. regulators are now aiming for a fleetwide fuel economy target of between 50 and 52.6 mpg by the 2025 model year, revised down from 54.5 mpg mostly as a result of increased sales of less fuel-efficient pickups and SUVs.
But credits for such things as environmentally friendly air conditioners and stop-start systems means that the actual fuel economy rating on the window sticker will be less than 54.5 mpg in nine years, and vehicles still will meet the target.
But, generally, full-line automakers that are heavily dependent on sales of pickups and SUVs — General Motors, Ford, Fiat Chrysler Automobiles — have to improve their fuel economy by as much as 5% each year to reach the goal.
Today’s electrical architectures are not going to be robust enough to carry the workload. Gustanski says the move to downsize and downspeed engines also has reduced the amount of power available for the ever-increasing electrical load.
“Automakers have backed themselves into the most effective and efficient engines ever, yet the pull for features and functionality is at its highest,” she said.
Not every electrical component will switch to 48-volt. Lights, radios, electric windows and door locks, for example, would stay 12-volt. Delphi’s vision is that vehicles with 48-volt systems would also have a strong regenerative braking system to capture much of the energy lost when a vehicle slows down.
48-volt’s time appears to have arrived, claims Gustanki
“Electrical architecture is not just about getting the voltage, getting everything powered and getting the signals going, it’s about the data speed,” says Gustanski. “It’s about the computing power and how you lay out the electrical system.”
Today’s cars, Gustanski says, process data at about 65 megabits, or 15,000 pieces of data, per second. “Tomorrow, it’s 1.5 gigabits,” she says, “or 100,000 pieces of data every time you blink your eyes.”