Model predictive controller design for throttle and wastegate control of a turbocharged engine

Abstract

In this paper, we consider the problem of turbocharged gasoline engine air-path control. Specifically, we apply linear Model Predictive Control (MPC) to coordinate throttle and turbocharger wastegate actuation for engine airflow and boost pressure control. Simplification of the prediction model used for the MPC reduces the memory requirement for implementation. We neglect the effects of variable cam timing in the prediction model, and instead, these effects are considered through a robustness analysis of the MPC to system variability. We compare two methods to achieve offset-free reference tracking, namely, the use of an integrator with actuator-saturation-based anti-windup logic, and the use of a Kalman filter to estimate plant-model mismatches. Evaluation of these methods for a vehicle acceleration scenario demonstrates advantages with using the Kalman-filter-based approach in the presence of system variability.