The world is talking about electric cars. And indeed: In January 2020, battery electric vehicles and plug-in hybrids achieved a market share of 6.5 percent according to the Federal Motor Transport Authority in Germany. As a result, high-voltage systems are taking up a large part of the discussion about the vehicle’s electrical system of the future. This neglects how important the 12-volt vehicle electrical system will remain in the future and how urgently innovative ideas are needed for this voltage level. After all, the number of functions in future vehicles will continue to increase, even independently of the powertrain. Those who fail to manage the resulting complexity will not be able to meet the high-quality requirements of the market.
To differentiate suitable from unsuitable solution paths, we from intedis – as a joint venture of the wiring system specialist LEONI and the electronics supplier Hella – recently conducted an extensive study. This involved initially investigating 34 possible E/E architectures for vehicles in the medium and luxury classes concerning their future viability. These architectures are derived from vehicle benchmarks of existing vehicles, publications by manufacturers and suppliers as well as our ideas with the potential for market entry. There were three decisive factors that we defined: Firstly, the architecture had to be fundamentally capable of providing robust power supply. Using a simulation model that takes into account the power consumption of all consumers, extreme situations such as a cold start or a short circuit to ground were simulated with a large number of consumers switched on. Secondly, the potential effects of individual faults were examined based on a fault tree analysis. Thirdly, we analyzed the functional realization on a logical level. Incidentally, about half of all theoretically possible wiring system architectures did not survive this selection process.