Optimization of a CNG Driven SI Engine Within a Parallel Hybrid Power Train by Using EGR and an Oversized Turbocharger with Active-WG Control IVK, University of Stuttgart

Format:

Conference/Event

Author/Creator:

Boland, Boland, author.

Contributor:

Bargende, Michael

Berner, Hans-Juergen

Conference Name:

SAE 2010 World Congress & Exhibition (2010-04-13 : Detroit, Michigan, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 2010

Summary:

The hybrid power train technology offers various prospects tooptimize the engine efficiency in order to minimize the CO₂emissions of an internal-combustion-engine-powered vehicle. Todaydifferent types of hybrid architectures like parallel, serial,power split or through-the-road concepts are commonly known. Toachieve lowest fuel consumption the following hybrid electricvehicle drive modes can be used: Start/Stop, pure electric/thermaldriving, recuperation of brake energy and the hybrid mode.The high complexity of the interaction between those powersources requires an extensive investigation to determine theoptimal configuration of a natural-gas-powered SI engine within aparallel hybrid power train. Therefore, a turbocharged 1.0-liter3-cylinder CNG engine was analyzed on the test bench. Using anoptimized combustion strategy, the engine was operated atstoichiometric and lean air/fuel ratio applying both high- andlow-pressure EGR. The range of possibilities given by hybrid powertrain architectures allows a phlegmatic operation strategy for theinternal-combustion engine, where the load demand is subject toslow transients. By applying an oversized turbocharger (widerturbine-neck cross-section) with Active-WG control (open wastegateat part-load operation) the engine efficiency was optimized overthe whole operation range.Secondary simulations of the longitudinal vehicle dynamicbehavior based on the measured steady-state performance maps fromthe engine test bench were carried out. To manage the differentpower sources a modified version of the common "EquivalentConsumption Minimization Strategy" was used. This"non-forward" looking operation strategy was developed toattain the initial state of battery charge at the end of thedriving cycle. Consequently no compensation calculation had to beperformed. Furthermore this strategy was designed to achieve lowestfuel consumption over the whole driving cycle. Hence, fuelconsumption and CO₂ emissions for legal driving cycles weredetermined

Notes:

Vendor supplied data

Publisher Number:

2010-01-0820

Access Restriction:

Restricted for use by site license