Common global architecture applied to automobile electrical distribution systems

Abstract

Electrical and electronic components have a prominent role in today's vehicles. Particularly during the last two decades, functionality has been added at an exponential rate, resulting in increased complexity, especially of the Electrical Distribution System (EDS), which is the backbone of the Electrical and Electronic System (EES). Increased content and complexity of electrical systems, together with pressure to reduce the design cycle time - to bring a larger variety of products to the market and at a faster pace - are forcing car companies to re-evaluate their existing electrical development processes. One of the ways that car makers have devised to accomplish this is a common EES architecture strategy, which consists in combining communization, standardization, reusability and best practices to create flexible EES architectural concepts that will be used in a higher number of derivative vehicles. This common architecture has several benefits, the most important being: reduction of development costs and time, which translates in less time for putting the products in the market; architecture, concepts and components reuse; rapid platform modifications, to adapt to market changes and regional preferences. The EES architecture choice for a vehicle is the result of the implementation of the desired functions in hardware and software. Many considerations need to be taken into account: costs, network capabilities, modularity, manufacturing, energy management, weight, among several others. The present work aims to explain these considerations, as well as the elements of the common EES, and in particular their impact on the EDS. Another important aspect for the successful implementation of the common architecture is the EDS development process. Despite the availability of a wide range of software tools, the current EDS approach is intensely manual, relying on design experts to define and maintain the interrelationships and complexities of the core design definition. There is a need to redefine the process, from concept to manufacture using a systems engineering approach, which would yield key benefits, like shorten development time, produce accurate harness manufacturing prints, reduce wiring costs by synchronizing all input and output data. An analysis of the tools and methods for design and validation of wire harnesses will be presented in the last two chapters of this thesis.