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In this paper, we compare controllers for the electronic throttle and variable geometry turbocharger in boosted stoichiometric gasoline direct injection engines. The control objectives are fast response and small overshoot of the intake manifold pressure. The problem is treated within the multi-objective optimization framework, applied to a simulation model of the engine. Pareto optimal fronts are constructed for each of the controllers and compared to each other. The best controller is thereby identified and further options to improve its response via preview-based control are discussed.

An engine torque modulation methodology is developed for use in engines equipped with electronic throttle control, ETC. It is shown through simulation that an engine with ETC is capable of following a transmission torque modulation command that includes a linearly increasing torque during the torque phase, a torque reduction during the inertia phase and a post-shift torque increase. It is also shown that such a strategy can be used to minimize the transmission output torque variation during a shift. The impact of engine indicated mean effective pressure, IMEP, variation on vehicle longitudinal acceleration is analyzed using Monte-Carlo simulation. It is shown that the IMEP induced variation in the vehicle acceleration is largely due to end of shift engine torque output timing errors. It is then recommended that during a shift the engine IMEP variation be held to a one-sigma variation of three percent or less.