Design and off-line tuning of a longitudinal driver model for EiL applications

Abstract

Tightnening emission regulations and increasing powertrain complexity lead car manufacturers to rely on novel testing methods in order to frontload development. Among these, Engine-in-the-Loop, that is, the coupling of a physical internal combustion engine (ICE) on a testbed with a virtual environment, shows great promise for emission- and consumption-related tasks. In particular, this study focuses on the driver model, a simple yet crucial component of the virtual environment. A longitudinal driver model is developed in Simulink based on the PI-regulation structure and augmented with anti-windup, cycle preview, and takeoff strategy. While the PI approach is generally chosen in the literature, this study details the implementation of the added functions, and proposes a method for the gains of the model to be tuned in simulation by considering engine dynamics, and using several performance indicators. The virtual driver is then tested in a complete EiL setup simulating an electric hybrid driveline and shows satisfactory cycle-following and overall behavior on a WLTC. Robustness of the tuning method is also studied by varying vehicle parameters on the EiL bench.

An Overview of Modelling and Energy Management Strategies for Hybrid Electric Vehicles

“…In order to ensure that the actual vehicle speed is close to the reference working speed, the driver model controls the demanded power supplied to the vehicle by adjusting the different throttle and brake pedal openings. The internal control is the vehicle's energy management system, which allocates the demanded power to the engine and battery via a built-in strategy [50,51].…”

Vehicle dynamics response due to the adjustment of K&C parameters with the aid of a dynamic simulator with 9 DOF and a correlated virtual model

“…It is noteworthy that the choice of steering ratio as the parameter for validation is because studies regarding the influence of this parameter in the vehicle dynamic behavior are well known and intuitive to interpret. 5,6 In this context, the use of simulation in the automotive industry has become a fundamental step during the development of new projects 7 and it has not been different in the chassis design, 8,9 especially regarding the suspension [10][11][12] and its correlated systems behavior. 13,14 Parallel to this, the parameters that govern vehicle kinematics and compliance are among the most important keys to a vehicle chassis design.…”

“…In this context, the use of simulation in the automotive industry has become a fundamental step during the development of new projects 7 and it has not been different in the chassis design, 8,9 especially regarding the suspension 10–12 and its correlated systems behavior. 13,14 Parallel to this, the parameters that govern vehicle kinematics and compliance are among the most important keys to a vehicle chassis design.…”