Abstract-New likelihood-based stochastic knock controllers have the potential to deliver significantly improved regulatory response relative to conventional strategies, while also maintaining a rapid transient response, but evaluation studies to date have only been performed in simulation. In this paper an experimental validation of the new strategy is presented. To demonstrate the robustness of the method, the algorithm is implemented on two different engine platforms, using two different knock intensity metrics, and evaluated under different operating conditions. One of these platforms is a five cylinder variable compression ratio engine, enabling the controller to be tested under different compression ratios, as well as different speed and load conditions. The regulatory and transient performance of the likelihood-based controller is assessed in a back-to-back comparison with a conventional knock controller and it is shown that the new controller is able to operate closer to the knock limit with less variation in control action without increasing the risk of engine damage.

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Résumé -Commande des gaz basée sur un modèle utilisant des compensateurs statiques et un placement de pôles -Au sein des moteurs à allumage commandé modernes, les gaz sont régulés par le boîtier de commande électronique (ECU ; Electronic Control Unit), qui permet la régulation directe par l'ECU du flux d'air et ainsi du couple moteur. Cela conduit à des exigences élevées quant à la vitesse et à la précision du régulateur qui positionne le papillon des gaz. Le problème de commande des gaz est compliqué par deux forts effets non linéaires, le frottement et le couple de mode de secours ("limp-home''). Cet article propose l'utilisation de deux compensateurs statiques, actifs simultanément, pour contrer ces effets et linéariser approximativement le système. Un régulateur PID est conçu pour le système linéarisé, où un placement de pôles est appliqué pour concevoir le régulateur PD et une partie I à gains paramétrés est ajoutée pour la robustesse par rapport aux erreurs de modèle. Un mode opératoire systématique destiné à générer les paramètres du compensateur et du régulateur à partir d'expériences en boucle ouverte est également développé. Les performances du régulateur sont évaluées à la fois par simulation, sur un problème de référence de commande des gaz, et expérimentalement. Une étude de robustesse a montré que la position de mode de secours constitue un paramètre important pour les performances du régulateur, ceci étant souligné par les écarts trouvés au cours des expériences. La méthode proposée pour l'identification des paramètres atteint la précision désirée. Abstract -Model-Based Throttle Control using Static Compensators and Pole Placement -In modern spark ignited engines, the throttle is controlled by the Electronic Control Unit (ECU), which gives the ECU direct control of the air flow and thereby the engine torque. This puts high demands on

Abstract:Using a bi-turbocharged configuration makes for better utilization of the exhaust energy and a faster torque response in V-type engines. A special surge phenomenon that should be avoided in bi-turbocharged engines is co-surge, which is when the two interconnected compressors alternately go into flow reversals. If co-surge should occur, the control system must be able to quell the oscillations with as little disturbance in torque as possible. This paper presents a model of a bi-turbocharged engine based on a Mean Value Engine Model that includes a MoreGreizer compressor model for surge. The model is validated against measured data showing that it captures the frequency and amplitude of the co-surge oscillation. The effect of momentum conservation in the pipes is investigated by adding this feature to the control volumes before and after the compressor. This gives a slightly better mass flow shape with the drawback of increased simulation time, due to more states and a higher frequency content in the model. A sensitivity analysis is performed to investigate which model parameters have most influence on the co-surge behavior. It is shown that the largest influence comes from the turbocharger inertia, the volumes after the compressor and the "zero mass flow pressure ratio" during flow reversal in the compressor. The model is used to investigate principles for control strategies to detect and quell co-surge. The detection algorithm is evaluated on measured data.