Advancing autonomous driving functions requires increasing redundancy, additional sensing, and interaction of the board-net components. Increasing redundancy can be realized by adding components, such as extra DC/DC converter for safe energy supply, however with focus on costs, volume und weight reduction, this solution would reduce the benefits of the advancing technology. The reduction of resources and energy, combined with additional features to enhance comfort and safety, presents challenges that must be addressed.
Future board nets for vehicles with increasing autonomous driving features must provide a reliable power supply for the growing number of components. These components are distributed throughout the entire vehicle body, each requiring a certain amount of power. This all requires energy storages, energy conversion and energy distribution, in different locations and on different levels. Low-volt (LV) board net topologies can be designed with different voltage levels: 12 V only, 48 V only, or a combination of both.
Zonal board net topologies offer the possibility to divide the requested power into limited amounts to stay below defined current limits of a 12 V board net, by defining zones optimized for this purpose. The 12 V board net only reduce s development costs due to the use of commodity components. This makes it suitable for small to medium-sized vehicles and may be a good option. However, changes in LV board net topology are necessary for medium and luxury segment vehicles. In these cases, the LV board net requires higher voltage to meet power demands in emergencies or for additional power supply. Solutions such as superCAP modules or batteries must be applied. 48 V board net voltage offers reduced cable cross-section at higher power levels but comes with additional components and increased development costs.
Various approaches will be discussed with defining the assumed vehicle segment and its benefits and drawbacks. Hella GmbH & Co. KGaA´s portfolio covers all components for the LV board net, and the experience covers challenges of interaction of those. The focus will be on energy conversion, storage, and distribution to meet the requirements of future board nets with features for autonomous driving functions.