Time-Varying Linear Observer for Torque Balancing on a DI Engine

Abstract Torque balancing for DI engines aims at eliminating the vibration mode and decreasing the level of emissions induced by disturbances such as variability in injectors efficiency, inertia and geometry between cylinders. The contribution of this article is to present a real-time experimental setup along with simulations and experimental results of estimation of the indicated torque of a DI engine. We build a time-varying linear model of the system and design a linear observer to estimate the indicated torque produced by each cylinder. This is achieved with the instantaneous engine speed as only measurement. This work can be used in a next step when unbalance could be corrected in an adaptive manner by controlling the mass injected into each cylinder.