What was inside the 1st edition of ECOSM?

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Ainsi, il n'est plus considéré comme « présomptueux » d'associer l'analyse de la stabilité du système en boucle fermée, à une analyse de robustesse. Les ingénieurs chargés de développer le contrôle moteur en ont même fait un de leurs soucis principaux. Afin de réguler la composition du combustible admis dans le cylindre avant la phase de combustion, le contrôle de la boucle de l'air est amplement remanié via diverses techniques automatiques, dans le but d proposed an overview of the current advances in the field of engine control and modelling. Engine control is playing an ever increasingly important place in the design of vehicles. Because engine control is intimately linked with electronics, its growth seems obvious and very fast to everybody and this, even though the technology inside remains in some cases rather conservative. The design of engine control based on the Control Theory is still rather young: it unites two scientific fields which are learning to know each other but each of which considers the other with (scientific) scepticism: on the one hand, powertrain system evolutions are doomed to failure (guaranteed to lead nowhere) if the new engine technologies (HCCI/LTC/CAI) do not come with adequate controllers; on the other hand, Control Theory does not provide a systematic response to a given problem without a thorough knowledge of the underlying physics via the modeling of the system considered.
In this context, the purpose of the congress was to highlight the interaction between different scientific fields involved in the same research objectives. The engine control combines the System Modeling stage and the Control Design stage taking the engine or vehicle issues into account to lead to successful innovation in the field of Powertrain engineering.

MODELING TO SUPPORT CONTROL OR MODEL-BASED CONTROL?
The first session related directly to the powertrain modeling approaches and simulation tools. In the control design process, the engine modelling task plays a central part as: -a simulator with physical based models which reproduce physical phenomena and dynamics to be controlled even if it does not correspond to the mathematical representation of the problem use in the control algorithms, -a simulation environment which will be used during the whole phase of Design, from the unitary test of the control law with a local model, to the test with the complete Powertrain simulator. This session opened with the keynote speech of Alain Dauron, "Model-Based Powertrain Control: many uses, no abuse", which gave an assessment of the contribution of modeling in the engine control design cycle. This use of modeling is often extended in terminology, in the powertrain development cycle to the Model-based-design, by forgetting its original signification as a state-observer. In this session, papers presented both complete modelling environments allowing the design and the test of part of the engine control [Albrecht] and aspects purely related to modeling system Editorial [Arsie]. As Powertrain Modeling is emergent, more in its application than its development, the following objectives to manage its development could be fixed: -define its perimeter of use, -demonstrate its real potential in supporting automobile development, -represent and follow the innovation of the powertrain system from the new combustion processes to its extension to the constraints domain which must also be modelled such as pollutant production or driveability.

TOWARDS THE LIMITS OF STABILITY: LEADING ROLE OF THE CONTROL
The second session focused on control issues produced by the new gasoline and diesel combustion processes such as HCCI, LTC or CAI. This session illustrated the fact that innovations in the field of new combustion systems provide cleaner and more efficient engines but involve more complex control issues. The engine technology is still of great importance but the engine control system becomes a critical part. Several papers illustrated this point and showed suitable control methods to face these specific problems. HCCI combustion is feasible under very restrictive running conditions (compositions of the gas, temperatures); a failure to respect them can result in a serious dysfunction of the combustion, potentially leading to system instability [Avolio, Karrelmeyer]. Adequate control becomes a necessary key element to ensure and maintain the stability of the system. Thus, the stability analysis of the closed-loop system, combined with a robustness analysis stops being a "theoretical vanity" but becomes a central issue for any engineer in engine control development. To control the composition of gases fed to the cylinder before the combustion phase, AirPath control is largely reorganized by using various automatic techniques with an objective to increase the band-width of the system for a better transient management of high EGR rates [Nitsche, Chauvin, Daeubler]. The AirPath plays a leading role in HCCI CI engine, by providing high EGR rate while maintaining high air flow rate: it involves the integration of the new turbocharger technologies with their dedicated control [Nitsche, Eriksson].

CONVERGENCE OF THE SI, CI ENGINE CONTROL
The third session began with the turbocharger control within a novel AirPath structure. Here, the associated control problem is independent of the engine combustion system. Lars Eriksson, in his keynote speech, "Modelling and Control of Turbocharged SI and DI engines", presented a synthesis on this fundamental subject dealing with the emergent engine technologies. The set of themes of gasoline engine control is proposed with different but complementary engine architectures and objectives: the downsizing concept with the use of variable valve timing camshafts where the model-based approach to manage the air and the residual gases trapped into the cylinder is prevalent [Le Solliec, Öberg]. The choice within the Air supervisor of the "dephasing" strategies is addressed via modelling. This method based on simulation support helps to optimize the potential benefits carried out by this technology [Filipi].

CONTROL OF HYBRID POWERTRAIN: A CONTINUATION OR A BREAKDOWN?
Last but not the least, the ECOSM congress finished with a session dedicated to the Control and Modeling of Advanced Power Sources. This is a topical subject which was not exhaustively handled in this session, but several papers give a good overview of Modeling and Control techniques applied in hybrid powertrain design. Lino Guzzella, througth his keynote speech, "Modeling and Control of Advanced Propulsion Systems", presented the different scientific topics concerned: from the Modeling paradigms to the Optimal Control.