12 Volt electric network evolutions for new functions integration: coasting function, recovery and boost with enhanced electric machines, and support for downsizing/down-speeding with a boosting support

摘要

Engine and vehicle electrification becomes a reality. However, when premium OEMs are targeting higher voltage than 12V to support their functions (i.e. 48V), most of the big volumes OEMs want affordable improved functions in order to provide fun to drive and fuel economy to their customers. Valeo, as a Tier 1 supplier, is focusing on developing products for fuel savings at the right cost for his OEMs, therefore Valeo is still focusing on 12V network while working in parallel on 48V products. Indeed, 12v still have a lot of potential improvements by using in a breakthrough manner this power supply. This paper will be divided in 4 parts: What are the capabilities of a 12V network and what we need to improve/modify to get the full benefits of this network? Which 12V system for which benefit? Coasting function, with a special focus on the product and the benefits. Evolution of the 12V alternator from high efficiency alternator to the iStars family. Electrical boosting capabilities associated with an improved 12V network. This paper will be based on Valeo's internal results on demo cars and also by system simulation. Finally, a focus will also be given on the engine control strategies in order to drive and welcome those new features.