Delphi has shown its new 42-volt belt alternator/starter system that
replaces separate starters and alternators with a high-output combined
belt-driven motor/alternator. This 42-volt system doesn’t replace the
existing 12-volt system, but rather has dual-voltage architecture of
42/14 volts.
While generating, the unit — and what Delphi refers to as eBox —
produces 42 volts, which charges a 36-volt battery. The eBox contains
an inverter and controller. A DC-DC converter is used to generate 14
volts from 42 volts, which is used to charge a conventional 12-volt
battery.
The 42-volt system will lead to a stop-start function that shuts
off the engine when the vehicle stops. The driver just needs to step on
the accelerator to restart the engine. Delphi claims this will lead to
an 8- to 10-percent improvement in fuel mileage in city traffic.
