Control-Oriented Models for Real-Time Simulation of Automotive Transmission Systems

N. Cavina, E. Corti, F. Marcigliano, D. Olivi, L. Poggio
2014 Oil & Gas Science and Technology  
and available online here Cet article fait partie du dossier thématique ci-dessous publié dans la revue OGST, Vol. 70, n°1, et téléchargeable ici Abstract -A control-oriented model of a Dual Clutch Transmission (DCT) was developed for realtime Hardware In the Loop (HIL) applications, to support model-based development of the DCT controller and to systematically test its performance. The model is an innovative attempt to reproduce the fast dynamics of the actuation system while maintaining a
more » ... lation step size large enough for real-time applications. The model comprehends a detailed physical description of hydraulic circuit, clutches, synchronizers and gears, and simplified vehicle and internal combustion engine submodels. As the oil circulating in the system has a large bulk modulus, the pressure dynamics are very fast, possibly causing instability in a real-time simulation; the same challenge involves the servo valves dynamics, due to the very small masses of the moving elements. Therefore, the hydraulic circuit model has been modified and simplified without losing physical validity, in order to adapt it to the real-time simulation requirements. The results of offline simulations have been compared to on-board measurements to verify the validity of the developed model, which was then implemented in a HIL system and connected to the Transmission Control Unit (TCU). Several tests have been performed on the HIL simulator, to verify the TCU performance: electrical failure tests on sensors and actuators, hydraulic and mechanical failure tests on hydraulic valves, clutches and synchronizers, and application tests comprehending all the main features of the control actions performed by the TCU. Being based on physical laws, in every condition the model simulates a plausible reaction of the system. A test automation procedure has finally been developed to permit the execution of a pattern of tests without the interaction of the user; perfectly repeatable tests can be performed for nonregression verification, allowing the testing of new software releases in fully automatic mode. Re´sume´-Mode´lisation oriente´e-controˆle pour la simulation en temps re´el des syste'mes de transmission automobile -Un mode'le oriente´vers le controˆle d'une transmission a'double embrayage (DCT, Dual Clutch Transmission) a e´te´de´veloppe´et imple´mente´en temps re´el dans un syste'me Hardware In the Loop (HIL), pour supporter le de´veloppement du controˆleur DCT et pour tester syste´matiquement ses performances. Le mode'le repre´sente une tentative innovatrice de reproduire les dynamiques rapides du syste'me d'actionnement tout en conservant une dimension de pas de calcul assez grande pour l'application en temps re´el. Le mode'le comprend une description physique de´taille´e du circuit hydraulique, des embrayages, des synchroniseurs et des engrenages, et des sous-mode'les simplifie´s du ve´hicule et du moteur ac ombustion interne. Comme l'huile circulant dans le syste'me est caracte´rise´e par un module de compressibilite´e´leve´, les dynamiques de pression sont tre's rapides, pouvant provoquer une
doi:10.2516/ogst/2013216 fatcat:2mabypktfrfq3h7nioq2ngcf7y