Rising fuel prices and stringent carbon emission regulations puts automotive industries under considerable pressure to improve fuel efficiency of vehicle as a result vehicle manufacturers always work towards development of new technologies to improve fuel efficiency of vehicle. Advancement in electronics controls is helping many improvements in vehicle features and energy efficiency. One such aspect of improvement in fuel economy is optimization of auto electrical charging via alternator operation. Alternator is connected with engine via a pulley and it draws mechanical power from the engine and converts that into electrical power which is used to charge the battery and cater the electrical consumer load of the vehicle. Alternator load on engine is increasing as more electrically driven accessories are getting added to the vehicle which results in additional fuel consumption of IC engine. An intelligent battery sensor enables real time SOC monitoring of the battery. With deployment of this device on vehicle, real time optimization of alternator operation based on instantaneous vehicle conditions and SOC feedback is possible. The idea is to control and optimize alternator operation as per vehicle power demand to optimize the energy loss and improve vehicle level fuel economy. This paper discusses control strategy to improve vehicle fuel economy. As initial evaluation and critical parameter optimization of these control strategies are important for fair assessment of the technology, a virtual vehicle level simulation model is developed for both traditional as well as smart alternator for like to like comparison and fuel economy simulations are carried out under different initial conditions and duty cycles. This paper presents fuel economy improvement quantification via digital simulation model. This paper also discusses impact of different critical parameters and initial conditions on fuel efficiency. A comparative analysis of differences in energy efficiency improvement w.r.t. different driving conditions like city and highway drive is also presented. Finally, simulation results and smart alternator logic impact on fuel efficiency improvements are validated through vehicle level testing data to summarize simulation model correlation with testing and actual overall fuel economy benefit of the technology.

Mr. Chaitanya Tiwari, DGM, TATA Motors