Dual voltage power supply system with 48 volts (BMW presentation)

As convened, here is a snapshot of Ottmar Sirch's presentation on 48 volt. This paper is scheduled during CESA 2012.
As an introduction, our expert from BMW reminds that the continuous increase of functionality for comfort, safety, driver assistance and infotainment systems as well as the insertion of innovations raise the requirements. In combination with the electrification of powertrain functions and ancillary units for CO2 reductions these requirements drive today´s vehicle power supply to its limits.

Then, Mr Sirch gives examples : Start-Stop-Function, Brake Energy Recuperation und electrification of mechanical driven systems as well as superpositioning of high power loads. The demand of electric energy and power as well as the cycling of accumulators have increased significantly.

In the future, OEMS will need High Power Recuperation (> 5 kW), Extended Start-Stop-Functions, E-Assist/E-Boost, eTurboCharge, as well as Electrification of ancillary units (electric climate compressor, electrification of chassis control systems) and new functions (front screen heating, electrohydraulic valve control)

As a conclusion, displacing all high power loads and implementation of new high power functions can reduce the requirements to the DC/DC converter and the 12-V-battery significantly.