Feedback Linearization Control for Enhanced Load Transient Performance in an Off-Road Diesel Engine With E-Booster

Abstract This paper proposes a multiple-input multiple-output (MIMO) nonlinear feedback linearization controller to enhance load transient performance in a 4.5L off-road diesel engine equipped with an e-booster (electrically driven compressor). The engine’s air-path subsystem is strongly coupled and highly nonlinear due to thermodynamic interactions between pressures and flows, making traditional single-input single-output (SISO) strategies less effective, especially during transients involving additional degrees of freedom such as e-booster actuation. A six-state mean value engine model based on physics is developed and used to design a non-linear MIMO controller that tracks key outputs: air–fuel ratio (AFR), engine speed and diluent-air ratio (DAR, representative of% EGR). Feedback linearization is applied to handle nonlinearities and decouple input–output dynamics, with a feedback PI controller added to improve robustness. The approach is compatible with production-level sensors, enabling practical implementation. The controller was evaluated during a simulated load transient from 100 Nm to 500 Nm in 0.3 seconds at constant speeds of 1200, 1600, and 1800 rpm, reflecting real-world off-road operating conditions. Compared to other linear control strategies, the proposed controller consistently achieved lower engine speed droop, improved DAR tracking, and minimized AFR dip.