Power distribution architecture evolution

Power distribution in vehicles is evolving because automotive architectures are changing as a whole, sparking the need for optimized wiring and increased software control. As shown in Figure 3, power distribution networks feed vehicle power supplies into a PDB, which distributes power to each zone. Each zone then distributes power locally to nearby ECUs, actuators or sensors.

Figure 4 illustrates different power distribution architectures. With the introduction of smart eFuses, and 48V systems, OEMs are enhancing their systems by replacing accessible fuse boxes managed by the driver with electronic fuse boxes managed by vehicle software. The transition to 48V power distribution will take time, as not all loads and actuators are ready to make the jump to this higher voltage level. As a result 12V loads will remain in first generation 48V systems. As OEMs continue to evaluate 48V power distribution, power distribution architectures will continue to evolve, possibly replacing 12V sources altogether.

48V systems enable further evolution by allowing you to use a backbone architecture where ZCMs distribute both primary and secondary power. It then becomes possible to remove the PDB as shown in Figure 5. The reduced load currents with 48V architectures allow more power distribution input and outputs in the ZCMs given lower thermal losses. This topology greatly simplifies the power distribution network.