Electric cars are coming. That much is sure, but a world with only battery electric cars is still decades away. In the interim, 48 volt electrical systems wil power many systems and sub-systems in conventional cars. Borg Warner is leading the way to the 48 volt future. Voltage is like water pressure in a pipe. The higher the pressure, the more work it can do. The obverse is that high pressures can make use of thinner pipes.
What can 48 volts systems do? They can power the electric steering and braking systems that are so critical to self driving cars. They can run air conditioning and heating systems at stop lights when a gasoline engine goes into shut down mode to boost fuel economy. They can zip windows up and down, open and close sunroofs, move power seats back and forth. In other words, they can relieve internal combustion engines from many of the chores that sap power and mileage from today’s cars.
One of the most exciting new applications for 48 volt systems is powering electric superchargers that spool up to their design speed of 130,000 rpm or more in a fraction of a second. Manufacturers are downsizing their internal combustion engines and adding turbochargers to increase power. But turbos have an inherent disadvantage. They only work when the flow of exhaust gasses is high.
While idling at a traffic light, turbos drop to low rpm. Once the light turns green, they can’t have any meaningful impact on engine power until engine revs get high enough to send a healthy stream of gasses out the exhaust manifold, spooling the turbo up to speed. An electric supercharger can fill in that gap, increasing engine power from just off idle until engine speeds are high enough to power up the turbo.
Borg Warner has several products that are at the leading edge of the 48 volt revolution. A major supplier to the automotive industry, these products are off the shelf items that car makers can incorporate into vehicles directly without the need for extensive R&D development, prototyping, and testing. Here are some of the products Borg Warner has available.
- eBooster – BorgWarner’s electrically driven compressor, which can be adapted for a wide range of combustion and hybrid applications, delivers boost on demand until the turbocharger takes over, enabling smaller four and six cylinder engines to deliver the same performance as much larger conventional V8 engines.
- iBAS – Otherwise known as an integrated belt alternator starter, they are designed to combine fast and quiet engine startup with high efficiency energy generation, torque assist, and regenerative braking.
- off-axis P2 module – Facilitates various hybrid functions, including regenerative braking, brake boosting, and pure electric driving. It achieves this in a more compact package compared to conventional on-axis modules through a chain-driven off-axis motor.
- Electric All-Wheel Drive (eAWD) – Traction and stability should not be jeopardized in hybrids and when compared to conventional AWD solutions this cost-neutral modification reduces fuel consumption by up to 9%.
One other advantage of 48 volt systems is that they do not require extensive safety shielding the way higher voltage components do. That saves weight and lowers installation costs. 48 volt components are now included in 17 models worldwide. Within a decade, the company expects that number to climb to 400 models with more than 22 million cars with 48 volt systems on the road.
Source and photo credits: Borg Warner