Abstract
Dilute combustion using exhaust gas recirculation (EGR) is a cost-effective method for increasing engine efficiency. At high EGR levels, however, its efficiency benefits diminish as cycle-to-cycle variability (CCV) intensifies. In this simulation study, cycle-to-cycle fuel control was used to reduce CCV by injecting additional fuel in operating conditions with sporadic misfires and partial burns. An optimal control policy was proposed that utilizes 1) a physics-based model that tracks in-cylinder gas composition and 2) a one-step-ahead prediction of the combustion efficiency based on a kernel density estimator. The optimal solution, however, presents a tradeoff between the reduction in combustion CCV and the increase in fuel injection quantity required to stabilize the charge. Such a tradeoff can be adjusted by a single parameter embedded in the cost function. Simulation results indicated that combustion CCV can be reduced by as much as 65% by using at most 1% additional fuel. Although the control design presented here does not include fuel trim to maintain A = 1 for three-way catalyst compatibility, it is envisioned that this approach would be implemented alongside such an external controller, and the theoretical contribution presented here provides a first insight into the feasibility of CCV control using fuel injection.
| Original language | English |
|---|---|
| Title of host publication | 2021 American Control Conference, ACC 2021 |
| Publisher | Institute of Electrical and Electronics Engineers Inc. |
| Pages | 1830-1835 |
| Number of pages | 6 |
| ISBN (Electronic) | 9781665441971 |
| DOIs | |
| State | Published - May 25 2021 |
| Event | 2021 American Control Conference, ACC 2021 - Virtual, New Orleans, United States Duration: May 25 2021 → May 28 2021 |
Publication series
| Name | Proceedings of the American Control Conference |
|---|---|
| Volume | 2021-May |
| ISSN (Print) | 0743-1619 |
Conference
| Conference | 2021 American Control Conference, ACC 2021 |
|---|---|
| Country/Territory | United States |
| City | Virtual, New Orleans |
| Period | 05/25/21 → 05/28/21 |
Funding
ACKNOWLEDGMENT This research was supported by the DOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office, and used resources at the National Transportation Research Center, a DOE-EERE User Facility at ORNL. This work was supported in part by the Laboratory Directed Research and Development Program of ORNL. NOTICE: This manuscript was authored in part by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan).