Design and experimental validation of a physics-based oxygen storage — thermal model for three way catalyst including aging

Control-oriented modelling of three-way catalytic converter for fuel-to-air ratio regulation in spark ignited engines

“…These models allow a deeper understanding of the phenomena related to the dynamic behaviour of the system, dealing with different complexity levels, from multi-dimensional models [3][4][5][6][7][8][9][10] to more common one-dimensional approaches. [11][12][13][14][15][16][17][18][19][20][21] Of course, all of them provide wide and accurate information regarding the converter state, but they cannot be used for real-time applications (RTA), which rule them out for control purposes. On the contrary, the integrator-type or black-box models [22][23][24][25][26][27][28] were the only feasible option for OSL estimation in RTA some years ago, when the computational capabilities of the common electronic control units (ECUs) were rather limited, but they are not accurate enough for today's requirements.…”

Modelling, control and diagnosis of aftertreatment systems based on three-way catalyst in spark-ignited engines

“…As a consequence of these advances, the proper AFR control around stoichiometric conditions was feasible, thus TWCs started to be a more competitive component, in terms of compactness and cost-performance, than the use of independent reduction and oxidation converters. Thanks to those rst TWCs, once above the light-o temperature (the temperature at which at least 50 % of the HC are converted) the emissions at steady conditions were markedly [24] and to deal with transient conditions [25,26] are ongoing tasks. Regarding the last one, the addition of ceriazirconia (CeO 2 − ZrO 2 ) is one of the last great advances [27], allowing the TWC to improve thermal stability and store oxygen, thereby, keeping low emissions even during AFR excursions dierent from stoichiometric conditions.…”

“…Focusing on the level of complexity, the multi-dimensional, detailed, rstprinciple models [121128] present excessive computational requirements for control purposes. Other rst-principle models in the literature are one-dimensional evolutions of the previous ones, developed with the idea of reducing the computational demand [25,26,129138]. But they often require a considerable amount of time to run simulations, and especially while properly identifying their parameters.…”

“…26 shows a zoomed view of the same test. At the beginning, the system is working at lean conditions with an OSL around 1 until the moment at which a signicant step towards rich is performed.…”

“…4.2 Zero-Dimensional control-oriented modelling of three-way catalystDetailed chemical rst-principle models of both, λ sensor[224] and TWC have been developed over the past three decades. These models allow a deeper understanding of the phenomena related to the dynamic behaviour of the system, dealing with dierent complexity levels, from multi-dimensional models[121127,225] to more common one-dimensional approaches as[26,128, 133140,226]. Of course, all of them provide wide and accurate information regarding the converter state, but they cannot be used for real-time applications (RTA), which rule them out for control purposes.…”