Avaliação experimental de um veículo equipado com alternador com desacoplamento eletromecânico e sistema stop-start

Abstract

During recent decades, the automotive industry has developed important initiatives in order to reduce global carbon dioxide emissions and to mitigate the man-made greenhouse effect. Multiple international agreements have promoted limits for CO2 emissions legislation and energy consumption of passenger cars. Energy saving technologies are being developed and have been implemented to increase the automotive efficiency, reducing fuel consumption and CO2 emissions. This research aimed at the experimental analysis of the isolated and combined application for three automotive technologies: an “intelligent alternator” system with electrical partial decoupling; Stop-Start system that promotes internal combustion engine automatic shutdowns at vehicle stops; and an electromechanical decoupling alternator (EDA) from the internal combustion engine crankshaft (based on an integrated pulley with an electromagnetic clutch). The latter technology system represents an innovation in terms of controlling the generation and electric energy usage, in which the decoupling events are performed according to the battery state of charge and internal combustion engine operating conditions. Thus, this strategy allows the complete engine crankshaft unloading in relation to the alternator's inertia and electromagnetic field. In tests carried out with a passenger vehicle it was possible to achieve reductions in the combined energy consumption (from urban FTP-75 and highway cycles combination) in the range of 2.17%, applying only the "intelligent alternator" technology, and up to 4.68% by the combination of Stop-Start system and ADE test configuration. The reductions in CO2 emissions were also significant, so that for the urban cycle there was a reduction of up to 6.51% and up to 1.50% for the highway cycle.