Mean Value Engine Model Including Spark Timing for Powertrain Control Application

A first principle based-control oriented gasoline engine model is proposed that is based on the mathematical model of the actual piston and crankshaft mechanism. Unlike conventional mean value engine models (MVEMs), which involve approximating the torque production mechanism with a volumetric pump, the proposed model obviates this rather over-simplistic assumption. The alleviation of this assumption leads to the additional features in the model such as crankshaft speed fluctuations and tension in bodies forming the mechanism. The torque production dynamics are derived through Lagrangian mechanics. The derived equations are reduced to a suitable form that can be easily used in the control-oriented model. As a result, the abstraction level is greatly reduced between the engine system and the mathematical model. The proposed model is validated successfully against a commercially available 1.3 L gasoline engine. Being a transparent and more capable model, the proposed model can offer better insight into the engine dynamics, improved control design and diagnosis solutions, and that too, in a unified framework.

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Turbocharged CNG Engines for Urban Transportation: Evaluation of Turbolag Reduction Strategies by Means of Computational Analyses

ASME 2009 Internal Combustion Engine Division Spring Technical Conference ◽

10.1115/ices2009-76067 ◽

2009 ◽

Cited By ~ 1

Author(s):

Mirko Baratta ◽

Ezio Spessa

Keyword(s):

Public Transportation ◽

High Performance ◽

Exhaust Valve ◽

Liquid Fuels ◽

Transient Condition ◽

Specific Reference ◽

Engine Model ◽

Spark Timing ◽

Pollutant Reduction ◽

1D Numerical Simulation

Nowadays, many urban buses for public transportation are fuelled by compressed natural gas (CNG), due to its potential for energy saving and pollutant reduction, with specific reference to particulate matter emissions. However, turbocharging is required to recover the gaseous-fuel related power gap with respect to more traditional engines running on liquid fuels. Therefore, turbolag reduction is fundamental to achieve high performance during engine transients. Significant support for the study of turbocharged CNG engines and guidelines for the turbomatching process can be provided by 1D numerical simulation tools. In this paper, the topic of turbolag reduction is analyzed, and different strategies, namely, Early-Exhaust Valve Opening-Variable Valve Actuation (E-EVO-VVA) and spark timing control for combustion retard (ComR), are analyzed by means of a specifically developed and calibrated GT-POWER® engine model. Tip-in maneuvers in which the engine was coupled to a torque hydraulic converter under stall conditions were investigated, so as to reproduce a typical load transient condition for an urban bus accelerating from engine idle. The best improvement of turbolag was obtained by combining E-EVO-VVA and ComR, with a reduction of turbolag ranging from 60% to 70%. When a limit on the incylinder pressure is introduced, in order to prevent excessive exhaust valve mechanical stresses, the higher achievable reduction in turbolag was found to be between 35% and 45%.

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Combined mean value engine model and crank angle resolved in-cylinder modeling with NOx emissions model for real-time Diesel engine simulations at high engine speed

Energy ◽

10.1016/j.energy.2015.05.072 ◽

2015 ◽

Vol 88 ◽

pp. 515-527 ◽

Cited By ~ 27

Author(s):

Fadila Maroteaux ◽

Charbel Saad

Keyword(s):

Diesel Engine ◽

Real Time ◽

Engine Speed ◽

Mean Value ◽

Nox Emissions ◽

Engine Model ◽

Crank Angle ◽

High Engine Speed

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A Correlation Methodology between AVL Mean Value Engine Model and Measurements with Concept Analysis of Mean Value Representation for Engine Transient Tests

10.4271/2017-24-0053 ◽

2017 ◽

Cited By ~ 1

Author(s):

Silvio A. Pinamonti ◽

Domenico Brancale ◽

Gerhard Meister ◽

Pablo Mendoza

Keyword(s):

Concept Analysis ◽

Mean Value ◽

Engine Model ◽

Value Representation

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Model-Based Actuator Trajectories Optimization for a Diesel Engine Using a Direct Method

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4001807 ◽

2010 ◽

Vol 133 (3) ◽

Cited By ~ 23

Author(s):

Michael Benz ◽

Markus Hehn ◽

Christopher H. Onder ◽

Lino Guzzella

Keyword(s):

Numerical Optimization ◽

Fuel Injection ◽

Direct Method ◽

Optimization Methods ◽

Optimization Method ◽

Mean Value ◽

Pollutant Emissions ◽

Pollutant Emission ◽

Transient Operation ◽

Engine Model

This paper proposes a novel optimization method that allows a reduction in the pollutant emission of diesel engines during transient operation. The key idea is to synthesize optimal actuator commands using reliable models of the engine system and powerful numerical optimization methods. The engine model includes a mean-value engine model for the dynamics of the gas paths, including the turbocharger of the fuel injection, and of the torque generation. The pollutant formation is modeled using an extended quasi-static modeling approach. The optimization substantially changes the input signals, such that the engine model is enabled to extrapolate all relevant outputs beyond the regular operating area. A feedforward controller for the injected fuel mass is used to eliminate the nonlinear path constraints during the optimization. The model is validated using experimental data obtained on a transient engine test bench. A direct single shooting method is found to be most effective for the numerical optimization. The results show a significant potential for reducing the pollutant emissions during transient operation of the engine. The optimized input trajectories derived assist the design of sophisticated engine control systems.

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