Authors: Autier, Erwin; Kouadri, Afia

Abstract: We present a study of a carbon dioxide transcritical power Rankine cycle using exhaust gas from fishing boat diesel engine, in order to reduce fuel dependence. Two types of cycle have been studied: with or without internal heat exchanger. This work has been realised without defining the geometry of the heat exchangers. This choice means that their effectiveness is not considered. Results show that an optimal pressure is found for each temperature below 438K for systems without internal heat exchanger and for each temperature below 503K for systems that have one. Moreover, results show that an optimal temperature exists for each pressure in systems with internal heat exchanger. Those facts prove that an optimisation of this system is possible at design of heat exchangers, and this, in correlation with all other parts: pump, expander, etc. Furthermore, presence of those optimal conditions shows us possibility of a future system control that enables to stay at optimum despite exhaust gas variations.

Keywords: Exhaust Gas Aftertreatment; Energy Management

Identifier: 10.3182/20091130-3-FR-4008.00018

Conference: 2009 IFAC Workshop on Engine and Powertrain Control, Simulation and Modeling

Location: IFP, France

Start Date: Mon Nov 30 2009 - End Date: Wed Dec 02 2009

Authors: Schallock, Robert; Peyton Jones, James; Muske, Kenneth R.

Abstract: This paper presents the results of an experimental study into the dynamic behaviour of a three-way automotive catalyst. The study suggests that the dynamic response of the catalyst can be significantly affected by a persistent memory effect in addition to the familiar oxygen storage / release dynamics of the system. In particular, the effects of prior rich or stoichiometric operation are shown to persist even after extended periods of lean operation. This memory effect is important, not only because of its potential impact on conversion efficiency, but also because of its impact on the repeatability of experiments carried out under what would appear to be similar operating conditions.

Keywords: Exhaust Gas Aftertreatment; Diagnostics; Spark Ignition

Identifier: 10.3182/20091130-3-FR-4008.00027

Conference: 2009 IFAC Workshop on Engine and Powertrain Control, Simulation and Modeling

Location: IFP, France

Start Date: Mon Nov 30 2009 - End Date: Wed Dec 02 2009

Authors: Vasile, Iulian; Doenitz, Christian; Voser, Christoph; Vetterli, Jan André; Onder, Christopher Harald; Guzzella, Lino

Abstract: Downsized and supercharged hybrid pneumatic vehicles may prove to be a viable and cost-efficient alternative to hybrid electric vehicles since they offer an almost as high fuel saving potential. One part of the fuel saving potential for this concept originates from the start/stop capability. This paper shows that the pneumatic motor mode can be used to start the engine rapidly enough to justify the use of a start/stop functionality. The paper presents fundamental considerations that have to be made for various possible hardware structures. A physics based model is introduced that describes the pneumatic start dynamics for any number of cylinders and any kind of valve profiles. Based on the validated model, the pneumatic engine start has been optimized and the optimal actuations have been implemented at the testbench for the engine under consideration. The experiments were carried out on a downsized and supercharged hybrid pneumatic prototype engine with two cylinders. It was shown that the engine's idling speed (1200 rpm) can be reached within 310 ms for a tank pressure of 10 bar.

Keywords: Hybrid and Electric Vehicles; Engine Control; Powertrain Control

Identifier: 10.3182/20091130-3-FR-4008.00013

Conference: 2009 IFAC Workshop on Engine and Powertrain Control, Simulation and Modeling

Location: IFP, France

Start Date: Mon Nov 30 2009 - End Date: Wed Dec 02 2009

Authors: Chasse, Alexandre; Hafidi, Ghizlane; Pognant-Gros, Philippe; Sciarretta, Antonio

Abstract: This paper focuses on the comparison of the offline optimization results with the online energy management laws obtained in a purely simulation environment and with a semi-physical testing equipment. Real-time implementation is introduced as an intermediate step of a complete chain of tools aimed at investigating the Energy Management System (EMS) problem. These tools comprise an offline optimizer based on Pontryagin Minimum Principle (PMP), the resulting Equivalent Consumption Minimization (ECMS) implemented in real time in a simulation platform and in an experimental environment (Hy-HiL test bench). Results illustrate the energy management laws issued by the different tools and compares the offline-generated ones with their online counterparts, both in terms of trajectories over time and in terms of global results (fuel consumption, SoC deviations)

Keywords: Powertrain Control; Hybrid and Electric Vehicles; Hardware-in-the-loop Simulation

Identifier: 10.3182/20091130-3-FR-4008.00015

Conference: 2009 IFAC Workshop on Engine and Powertrain Control, Simulation and Modeling

Location: IFP, France

Start Date: Mon Nov 30 2009 - End Date: Wed Dec 02 2009

Authors: Majecki, Pawel; Javaherian, Hossein; Grimble, Michael

Abstract: The problem of simultaneous air-fuel ratio regulation and torque tracking in a spark ignition engine with electronic throttle control is considered. The proposed methodology involves the use of a set of piecewise-affine models to represent the nonlinear engine dynamics. These models are the basis of a supervisory multiple-model control scheme, which, in its simplest form, consists in switching among the predefined bank of controllers. In the following a monitoring signal generator is driven by a bank of observers, and a supervisor ensures the robustness of the switching scheme. An optimal linear-quadratic cost function enables the trade-off between emissions performance and drivability to be adjusted. Simulation results using the data obtained from a vehicle with a 5.3L V8 engine on Federal Test Procedure (FTP) driving cycles are presented, with a nonlinear regression model of the engine identified from the FTP data. The results indicate that both tight lambda regulation and fast torque tracking are possible using the proposed designs.

Keywords: Control Architectures; Powertrain Control; Engine Modeling

Identifier: 10.3182/20091130-3-FR-4008.00004

Conference: 2009 IFAC Workshop on Engine and Powertrain Control, Simulation and Modeling

Location: IFP, France

Start Date: Mon Nov 30 2009 - End Date: Wed Dec 02 2009

Authors: Mrosek, Matthias; Isermann, Rolf

Abstract: An extension of the air- and exhaust-system with a two path EGR-system consisting of a conventional cooled high-pressure EGR and a cooled low-pressure EGR has the potential to significantly reduce the NOx-emissions. Model based control structures and model based controller calibration can handle the increasing complexity of the air-system. An automated controller calibration based on a semi-physical mean value model of reduced complexity is presented. The system configuration of a two path EGR system is introduced. Its static and dynamic properties are investigated. Additional to the static couplings in the classical air-path new couplings appear. Also the system’s dynamic properties are investigated. A decentralised gain scheduled PI(D)-control approach is chosen to control the variables air mass flow rate, high-pressure EGR mass flow rate and charge-air pressure. The controller maps depend on the engine operation point and are calibrated by a local linearisation of the semi-physical model. Couplings resulting on the low-pressure EGR-path are compensated by a semi-physical feed forward control.

Keywords: Engine Control; Exhaust Gas Aftertreatment; Engine Modeling

Identifier: 10.3182/20091130-3-FR-4008.00008

Conference: 2009 IFAC Workshop on Engine and Powertrain Control, Simulation and Modeling

Location: IFP, France

Start Date: Mon Nov 30 2009 - End Date: Wed Dec 02 2009

Authors: Andrianov, Denis Igorevich; Dingli, Robert Joseph; Brear, Michael; Manzie, Chris

Abstract: A one-dimensional model of a monolithic three-way catalyst is presented, featuring a reduced order chemical kinetic scheme with oxygen storage and comprised of 10 reactions. The model behaviour is validated against measurements taken from air/fuel ratio sweeps as well as European emission drive cycle data, covering a broad range of flow velocities, gas composition and inlet temperatures. The effects of grid resolution and oxygen storage reactions on the predicted light-off time and conversion efficiency are investigated to provide insight into the minimum modelling requirements.

Keywords: Exhaust Gas Aftertreatment; Engine Control

Identifier: 10.3182/20091130-3-FR-4008.00026

Conference: 2009 IFAC Workshop on Engine and Powertrain Control, Simulation and Modeling

Location: IFP, France

Start Date: Mon Nov 30 2009 - End Date: Wed Dec 02 2009

Authors: Thomasson, Andreas; Eriksson, Lars; Leufven, Oskar; Andersson, Per

Abstract: The torque response of an engine is important for driver acceptance. For turbocharged spark ignited (TCSI) engines this is tightly connected to the boost pressure control, which is usually achieved with a wastegate. A challenging scenario is when the throttle is fully open and the load is essentially controlled by the wastegate. First a model for the pneumatic wastegate actuator and air control solenoid is developed. The wastegate model consists of three submodels; the actuator pressure, the static position, and an additional position dynamics. A complete engine model is constructed by including the actuator model in a Mean Value Engine Model (MVEM) for a TCSI engine. This model describes the transient boost pressure response to steps in wastegate control inputs. The subsystems and complete MVEM are validated on an engine test bench and it explains the overshoot seen in the step responses. The model is used to study the system response and give insight into the dominating phenomena and it points out that the engine speed is important for the response. Further, for each speed it is sufficient to model the system as a second order linear system, that captures an overshoot. A controller consisting of a mapped feedforward loop and a gain scheduled feedback loop is developed together with a tuning method based on the IMC framework for the feedback loop. The controller and tuning method is shown to achieve the desired boost pressure behavior both on the complete MVEM and on real engines. The experimental validation is carried out both in an engine test cell and in a vehicle.

Keywords: Engine Modeling; Engine Control; Turbocharging

Identifier: 10.3182/20091130-3-FR-4008.00012

Conference: 2009 IFAC Workshop on Engine and Powertrain Control, Simulation and Modeling

Location: IFP, France

Start Date: Mon Nov 30 2009 - End Date: Wed Dec 02 2009