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Closed-Loop Combustion Control for a 6-Cylinder Port-Injected Natural-gas Engine

Kaiadi, Mehrzad LU ; Tunestål, Per LU and Johansson, Bengt LU (2009) SAE International Powertrains, Fuels and Lubricants Congress In SAE International Journal of Fuels and Lubricants 1(1). p.1232-1241
Abstract
High EGR rates combined with turbocharging has been identified as a promising way to increase the maximum load and efficiency of heavy-duty spark ignition engines. With stoichiometric conditions a three-way catalyst can be used which means that regulated emissions can be kept at very low levels. Obtaining reliable spark ignition is difficult however with high pressure and dilution. There will be a limit to the amount of EGR that can be tolerated for each operating point. Open-loop operation based on steady state maps is difficult since there is substantial dynamics both from the turbocharger and from the wall heat interaction. The proposed approach applies standard closed-loop lambda control for controlling the overall air/fuel ratio for a... (More)
High EGR rates combined with turbocharging has been identified as a promising way to increase the maximum load and efficiency of heavy-duty spark ignition engines. With stoichiometric conditions a three-way catalyst can be used which means that regulated emissions can be kept at very low levels. Obtaining reliable spark ignition is difficult however with high pressure and dilution. There will be a limit to the amount of EGR that can be tolerated for each operating point. Open-loop operation based on steady state maps is difficult since there is substantial dynamics both from the turbocharger and from the wall heat interaction. The proposed approach applies standard closed-loop lambda control for controlling the overall air/fuel ratio for a heavy-duty, 6-cylinder, port-injected natural gas engine. A closed-loop load control is also applied for keeping the load at a constant level when using EGR. Furthermore, cylinder pressure-based dilution limit control is applied on the EGR in order to keep the coefficient of variation at the desired level of 5%. This way confirms that the EGR ratio is kept at its maximum stable level all times. Pumping losses decrease due to the further opening of the throttle, thereby the gas exchange efficiency improves and since the regulator keeps track of the changes the engine all the time operates in a stable region. Our findings show that excellent steady-state performance can be achieved using closed-loop combustion control for keeping the EGR level at the highest level while the stability level is still good enough. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
keywords
Internal Combustion Engine, Natural Gas, Control
in
SAE International Journal of Fuels and Lubricants
volume
1
issue
1
pages
10 pages
conference name
SAE International Powertrains, Fuels and Lubricants Congress
external identifiers
  • Other:SAE Technical Paper 2008-01-1722
  • Scopus:77953240575
language
English
LU publication?
yes
id
9ae497dd-850e-4018-bb83-016087d4acdf (old id 1396318)
alternative location
http://saefuel.saejournals.org/content/1/1/1232.abstract
date added to LUP
2009-05-13 12:22:32
date last changed
2017-01-01 08:08:50
@inproceedings{9ae497dd-850e-4018-bb83-016087d4acdf,
  abstract     = {High EGR rates combined with turbocharging has been identified as a promising way to increase the maximum load and efficiency of heavy-duty spark ignition engines. With stoichiometric conditions a three-way catalyst can be used which means that regulated emissions can be kept at very low levels. Obtaining reliable spark ignition is difficult however with high pressure and dilution. There will be a limit to the amount of EGR that can be tolerated for each operating point. Open-loop operation based on steady state maps is difficult since there is substantial dynamics both from the turbocharger and from the wall heat interaction. The proposed approach applies standard closed-loop lambda control for controlling the overall air/fuel ratio for a heavy-duty, 6-cylinder, port-injected natural gas engine. A closed-loop load control is also applied for keeping the load at a constant level when using EGR. Furthermore, cylinder pressure-based dilution limit control is applied on the EGR in order to keep the coefficient of variation at the desired level of 5%. This way confirms that the EGR ratio is kept at its maximum stable level all times. Pumping losses decrease due to the further opening of the throttle, thereby the gas exchange efficiency improves and since the regulator keeps track of the changes the engine all the time operates in a stable region. Our findings show that excellent steady-state performance can be achieved using closed-loop combustion control for keeping the EGR level at the highest level while the stability level is still good enough.},
  author       = {Kaiadi, Mehrzad and Tunestål, Per and Johansson, Bengt},
  booktitle    = {SAE International Journal of Fuels and Lubricants},
  keyword      = {Internal Combustion Engine,Natural Gas,Control},
  language     = {eng},
  number       = {1},
  pages        = {1232--1241},
  title        = {Closed-Loop Combustion Control for a 6-Cylinder Port-Injected Natural-gas Engine},
  volume       = {1},
  year         = {2009},
}