Zhao, Kai (Sophia University), Shi, Haoyun (Sophia University), Shen, Tielong (Sophia University)

Combustion Variation Control of SI Engines Via Hypothesis Testing and EGR Step Valve

Scheduled for presentation during the Regular session "Engine control system" (MoBT1), Monday, August 23, 2021, 16:30−16:50, Room T1

6th IFAC Conference on Engine and Powertrain Control, Simulation and Modeling, August 23-25, 2021, Tokyo, Japan

This information is tentative and subject to change. Compiled on April 26, 2024

Abstract

In gasoline engines, the variation of the combustion is often evaluated by the coefficient of variance (CoV) of the indicated mean effective pressure (IMEP). Due to the involvement of the mean and the standard deviation in the calculation, a large number of engine cycles are necessary for an accurate estimation of the CoV. However, in the case of real-time engine control, the number of available data is often limited. Thus, statistic-based methods have to be applied to determine whether the CoV is greater or less than a given threshold. In this work, a hypothesis testing based on McKay's approximation is proposed to statistically evaluate the CoV of IMEP. The results of the proposed testing method are then used to control the EGR valve step to maintain the IMEP CoV at a given threshold. The proposed method was validated on a testbench with a production gasoline engine.