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Over the past few years, innovative engine layouts have enabled significant reductions in both fuel consumption and pollutant emissions. However, exponential growth of powertrain control strategies complexity has inevitably accompanied these achievements. As a result, control and calibration development time and effort have become an ever-growing concern in powertrain design. An illustrative example of this complexity is Diesel Particulate Filters (DPF), which requires periodic regeneration to eliminate the accumulated soot. The main challenge for a DPF is to enhance the efficiency of these regeneration events, which depend largely on the quality of the regeneration temperature control. In this paper, we describe the DPF regeneration process, especially the main constraints and identification tests. We then give a simulation based comparison of two model based control solutions for the DPF thermal control during regeneration.

This paper presents an after-treatment architecture combining a close coupled NOx trap and an under floor NOx trap. Instead of simply increasing the volume of the catalyst, we propose to broaden the active temperature window by splitting the LNT along the exhaust line. In order to design this architecture, a complete 1D model of NOx trap has been developed. Validated with respect to experimental data, this model has been useful to define the two volumes of LNT, making significant savings on the test bench exploitation. However, one of the main difficulties to operate the proposed architecture is the NOx purge and sulfur poisoning management. In order to optimize the NOx and sulfur purge launches, we have developed a control strategy based on an embedded reduced LNT model. These strategies have been validated on different driving cycles, by the means of simulation and of vehicle tests using rapid prototyping tools.

Diesel Particulate Filters (DPF) are now considered as efficient solutions to reduce Diesel PM emissions. Concerned by environment, Renault will equip all serial production Diesel vehicles with this technology. The main issue for these devices is the periodical regeneration necessary to eliminate the accumulated soot. The challenging enhancement of the regeneration event can be achieved with a better regeneration temperature control. For this purpose, a controller based on a physical model is proposed to manage the DPF temperature during active regeneration. This paper describes the methodology which has been followed to design this controller. In a first step, a reduced physical model has been developed and validated with experimental data. In a second step, two model-based controllers have been studied: a robust LPV (Linear Parameter Varying) and a gain scheduling PID..Special attention has been paid to the simplification as far as possible of the controller tuning process.