Making the transition to 42V electrically-powered "beltless engines" If it comes, transition to 42V electrically-powered beltless engines will be difficult, but presents opportunities to engineers By Qi Wang, Keithley Instruments To meet increasing electrical power demands, automakers are moving to increase vehicle battery voltage from today"s 14V to approximately 42V. It"s been more than 40 years since car makers switched from the standard 6V system - a change triggered by similar power considerations.
Since then, vehicle electrical power consumption has increased by more than 50 percent. Next-generation cars will have even more electronics and require a power source with an output of more than 3kW, the limit of today"s 14V system. A 42V system will deliver around 8kW and allow better management of the higher power requirements.
A 42V system sets the stage for ADVANCED technologies that will allow a switch from mechanical belt-driven systems to electrically-powered ones. Possibilities include electric power steering, electromechanical brakes, electrical HVAC systems, electromagnetic valve trains, integrated starter-generators and electronic ride CONTROL systems. The so-called "beltless engine" of the future will be another reason for lower weight packaging (because accessories can be located outside the engine compartment), leading to higher efficiency that improves gas mileage and reduces emissions.
Before 42V systems can be adopted widely, many engineering problems must be addressed, including the engine/electrical system architecture and a migration strategy (dual 14/42V systems vs. straight 42V systems). Short-term challenges associated with dual voltage systems include more wiring, extra weight and added complexity.
Regardless of migration path, suppliers need time to develop new components and a part identification system that distinguishes between 14V and 42V parts.
