Current significant challenges in the automotive industry for
increasing fuel economy and reducing CO₂ emissions remain with
traditional combustion engines. Moderately small increases in fuel
efficiency lead to major reductions in CO₂ emissions, primarily due
to large production volumes utilizing incremental fuel saving
technologies.
Enhancements of today's vehicle powertrains, including
micro-hybrids and mild-hybrids with stop-start systems, and
coasting and energy recuperation have shown a positive cost benefit
and shorter payback period. This is identified when the technology
is compared to more complex and expensive HEVs (Hybrid Electric
Vehicles) and BEVs (Battery Electric Vehicles).
This paper describes the development of a baseline conventional
vehicle model for estimating fuel savings and CO₂ reduction; it
provides a benchmark for the development of fuel saving energy
management technologies such as stop-start, coasting, and dual
voltage architecture with regenerative braking and
"on-demand" fuel senders. It will be shown that a
stop-start system will provide a simulated 2.9% FE (Fuel Economy)
benefit for the EPA unadjusted combined city/highway driving
cycles. Also enhanced stop-start with aggressive coasting with
engine-off (≺100 km/hr) provides an additional benefit of 7.1%.
In addition, this paper describes a case study for the
development of a HIL (Hardware-In-the-Loop) simulator which makes
use of the conventional baseline model. The HIL system measures
fuel savings of replacing a "100% driven" fuel system
with an "on-demand" fuel delivery system. The case study
will show a 40% CO₂ reduction over "100% driven" DC pump
with a DC "on-demand" pump and an additional 22% CO₂
reduction for the BLDC "on-demand" pump for the EPA
city/highway driving cycles using a Mini Cooper vehicle model.