Reactivity controlled compression ignition (RCCI)
engines center on a combustion strategy with higher thermal
efficiency, lower particulate matter (PM), and lower oxides
of nitrogen (NOx) emissions compared to conventional diesel
combustion (CDC) engines. However, real time optimal control
of RCCI engines is challenging during transient operation due
to the need for high fidelity combustion models. Development
of a simple, yet accurate control-oriented RCCI model from
physical laws is time consuming and often requires substantial
calibrations. To overcome these challenges, data-driven models
can be developed. In this paper, a data-driven linear parametervarying
(LPV) model for an RCCI engine is developed. An LPV
state space model is identified to predict RCCI combustion
phasing as a function of multiple RCCI control variables. The
results show that the proposed method provides a fast and
reliable route to identify an RCCI engine model. The developed
model is then used for the design of a model predictive
controller (MPC) to control crank angle for 50% fuel burnt
(CA50) for varying engine conditions. The experimental results
show that the designed MPC with the data-driven LPV model
can track desired CA50 with less than 1 crank angle degree
(CAD) error against changes in engine load.
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Data-driven Modeling and Predictive Control of Combustion Phasing for RCCI Engines
Reactivity controlled compression ignition (RCCI)
engines center on a combustion strategy with higher thermal
efficiency, lower particulate matter (PM), and lower oxides
of nitrogen (NOx) emissions compared to conventional diesel
combustion (CDC) engines. However, real time optimal control
of RCCI engines is challenging during transient operation due
to the need for high fidelity combustion models. Development
of a simple, yet accurate control-oriented RCCI model from
physical laws is time consuming and often requires substantial
calibrations. To overcome these challenges, data-driven models
can be developed. In this paper, a data-driven linear parametervarying
(LPV) model for an RCCI engine is developed. An LPV
state space model is identified to predict RCCI combustion
phasing as a function of multiple RCCI control variables. The
results show that the proposed method provides a fast and
reliable route to identify an RCCI engine model. The developed
model is then used for the design of a model predictive
controller (MPC) to control crank angle for 50% fuel burnt
(CA50) for varying engine conditions. The experimental results
show that the designed MPC with the data-driven LPV model
can track desired CA50 with less than 1 crank angle degree
(CAD) error against changes in engine load.
more »
« less
- Award ID(s):
- 1762520
- NSF-PAR ID:
- 10112262
- Date Published:
- Journal Name:
- Proceedings of the ... American Control Conference
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Reactivity controlled compression ignition (RCCI) engines center on a combustion strategy with higher thermal efficiency, lower particulate matter (PM), and lower oxides of nitrogen (NOx) emissions compared to conventional diesel combustion (CDC) engines. However, real time optimal control of RCCI engines is challenging during transient operation due to the need for high fidelity combustion models. Development of a simple, yet accurate control-oriented RCCI model from physical laws is time consuming and often requires substantial calibrations. To overcome these challenges, data-driven models can be developed. In this paper, a data-driven linear parameter varying (LPV) model for an RCCI engine is developed. An LPV state space model is identified to predict RCCI combustion phasing as a function of multiple RCCI control variables. The results show that the proposed method provides a fast and reliable route to identify an RCCI engine model. The developed model is then used for the design of a model predictive controller (MPC) to control crank angle for 50% fuel burnt (CA50) for varying engine conditions. The experimental results show that the designed MPC with the data-driven LPV model can track desired CA50 with less than 1 crank angle degree (CAD) error against changes in engine load.more » « less
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Reactivity controlled compression ignition (RCCI) is a promising low temperature combustion (LTC) regime that offers lower nitrogen oxides (NOx), soot and particulate matter (PM) emissions along with higher combustion efficiency compared to conventional diesel engines. It is critical to control maximum pressure rise rate (MPRR) in RCCI engines in order to safely and efficiently operate at varying engine loads. In this paper, a data-driven modeling (DDM) approach using support vector machines (SVM) is adapted to develop a linear parameter-varying (LPV) representation of MPRR for RCCI combustion. This LPV representation is then used in the design of a model predictive controller (MPC) to control crank angle of 50% of fuel mass fraction burn (CA50) and indicated mean effective pressure (IMEP) while limiting the MPRR. The results show that the LPV-MPC control strategy can track CA50 and IMEP with mean tracking errors of 0.9 CAD and 4.7 kPa, respectively, while limiting the MPRR to the maximum allowable value of 5.8 bar/CAD.more » « less
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