INTRODUCTION In response to the more stringent international standards concerning the environmental impact of the road traffic, automobile manufacturers are currently developing new vehicle concepts featuring lower emissions and fuel consumption ([ 1,2]). One promising approach is the partial electrification of traditional powertrains: Hybrid Electric Vehicles (HEVs). These innovative systems attempt to couple the advantages of traditional vehicles with electric propulsion. However, the resulting powertrain is complex and requires a suitable operating management strategy to properly exploit the expected benefits. ([ 3,4,5]). In this framework, simulation can play a significant role to properly identify the optimal hybrid operating management strategy. In this paper, the fuel economy, NO x emissions and combustion noise of a parallel hybrid architecture are analyzed through a dedicated numerical code. The model reproduces real-driver behavior and, taking into accountbattery performance limitations, determines the power split between the Internal Combustion Engine (ICE) and the Electric Machine (EM). As far as the powertrain layout is concerned, the traditional starter has been replaced with a high-voltage Belt Alternator Starter (BAS) in a light-duty diesel engine passenger car. The design of the resulting drivetrain is very similar to that of a traditional vehicle. Moreover, engine Stop&Start, regenerative braking, electric boosting and ICE load point shift are enabled. Among the most common Hybrid Operating Strategies (HOS) that are available in the literature, the adopted approach is based on the reduction of total losses ([ 6]). SIMULATION MODEL The simulation model was developed using GT-Drive software, a Gamma Technologies Inc. tool for the zero- dimensional simulation of vehicles and powertrains ([ 7]). A 2012-01-1008 Published 04/16/2012 Copyright © 2012 SAE International doi:10.4271/2012-01-1008 saealtpow.saejournals.org Analysis of Various Operating Strategies for a Parallel-Hybrid Diesel Powertrain with a Belt Alternator Starter Edoardo Morra and Ezio Spessa Politecnico di Torino Claudio Ciaravino and Alberto Vassallo General Motors Company ABSTRACT The sustainable use of energy and the reduction of pollutant emissions are main concerns of the automotive industry. In this context, Hybrid Electric Vehicles (HEVs) offer significant improvements in the efficiency of the propulsion system and allow advanced strategies to reduce pollutant and noise emissions. The paper presents the results of a simulation study that addresses the minimization of fuel consumption, NO x emissions and combustion noise of a medium size passenger car. Such a vehicle has a parallel-hybrid diesel powertrain with a high-voltage belt alternator starter. The simulation reproduces real-driver behavior through a dynamic modeling approach and actuates an automatic power split between the Internal Combustion Engine (ICE) and the Electric Machine (EM). Typical characteristics of parallel hybrid technologies, such as Stop&Start, regenerative braking and electric power assistance, are implemented via an operating strategy that is based on the reduction of total losses. After model calibration and validation against available experimental data, various Hybrid Operating Strategies (HOS) have been examined. These are investigated over the New European Driving Cycle (NEDC) and the Artemis Urban Cycle (AUC) in terms of fuel economy, NO x emissions and combustion noise. Finally, optimal calibrations are suggested as the best compromise between all the analyzed targets. ____________________________________ 231CITATION: Morra, E., Spessa, E., Ciaravino, C. and Vassallo, A., "Analysis of Various Operating Strategies for a Parallel- Hybrid Diesel Powertrain with a Belt Alternator Starter," SAE Int. J. Alt. Power. 1(1):2012, doi:10.4271/2012-01-1008.Downloaded from SAE International by University of Michigan, Saturday, July 28, 2018coupled code in Matlab envir