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Model based TDC offset estimation from motored cylinder pressure data

Tunestål, Per LU (2009) 2009 IFAC Workshop on Engine and Powertrain Control, Simulation and Modeling, E-COSM'09 42. p.241-247
Abstract

Finding the correct top dead center (TDC) offset for an internal combustion engine is harder than it seems. This paper introduces a novel method to find the TDC offset based on a simple assumption that the heat loss power through the combustion chamber walls is constant for motored cycles in a narrow crank angle interval around TDC. The proposed method uses nonlinear least squares optimization to find the combination of specific heat ratio and TDC offset that makes the heat loss power as constant as possible. The standard deviation of the TDC estimate is approximately 0.05° crank angle (CA) when using a crank resolution of 0.2°CA for the measurements. The bias of the TDC estimate is in the 0-0.02°CA range both when comparing to... (More)

Finding the correct top dead center (TDC) offset for an internal combustion engine is harder than it seems. This paper introduces a novel method to find the TDC offset based on a simple assumption that the heat loss power through the combustion chamber walls is constant for motored cycles in a narrow crank angle interval around TDC. The proposed method uses nonlinear least squares optimization to find the combination of specific heat ratio and TDC offset that makes the heat loss power as constant as possible. The standard deviation of the TDC estimate is approximately 0.05° crank angle (CA) when using a crank resolution of 0.2°CA for the measurements. The bias of the TDC estimate is in the 0-0.02°CA range both when comparing to measurements with a TDC sensor and with simulated motored cycles. The method can be used both for calibration and on-board diagnostics purposes e.g. during cranking, fuel cut-off or engine switch-off.

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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
Cylinder pressure, Estimation, Least squares estimation, LLS, NLLS, TDC offset
host publication
IFAC Proceedings Volumes
volume
42
edition
26
pages
7 pages
conference name
2009 IFAC Workshop on Engine and Powertrain Control, Simulation and Modeling, E-COSM'09
conference location
Rueil-Malmaison, France
conference dates
2009-11-30 - 2009-12-02
external identifiers
  • scopus:80051513031
ISBN
1474-6670
DOI
10.3182/20091130-3-FR-4008.00032
project
Competence Centre for Combustion Processes
language
English
LU publication?
yes
id
51c24435-064e-4d84-9714-674e0391bf1b
date added to LUP
2017-12-14 17:27:21
date last changed
2021-06-16 02:07:39
@inproceedings{51c24435-064e-4d84-9714-674e0391bf1b,
  abstract     = {<p>Finding the correct top dead center (TDC) offset for an internal combustion engine is harder than it seems. This paper introduces a novel method to find the TDC offset based on a simple assumption that the heat loss power through the combustion chamber walls is constant for motored cycles in a narrow crank angle interval around TDC. The proposed method uses nonlinear least squares optimization to find the combination of specific heat ratio and TDC offset that makes the heat loss power as constant as possible. The standard deviation of the TDC estimate is approximately 0.05° crank angle (CA) when using a crank resolution of 0.2°CA for the measurements. The bias of the TDC estimate is in the 0-0.02°CA range both when comparing to measurements with a TDC sensor and with simulated motored cycles. The method can be used both for calibration and on-board diagnostics purposes e.g. during cranking, fuel cut-off or engine switch-off.</p>},
  author       = {Tunestål, Per},
  booktitle    = {IFAC Proceedings Volumes},
  isbn         = {1474-6670},
  language     = {eng},
  pages        = {241--247},
  title        = {Model based TDC offset estimation from motored cylinder pressure data},
  url          = {http://dx.doi.org/10.3182/20091130-3-FR-4008.00032},
  doi          = {10.3182/20091130-3-FR-4008.00032},
  volume       = {42},
  year         = {2009},
}