Model-Based Calibration of a Gasoline-Fueled Spark Ignition Engine for Torque Control Application Using Mean Value Engine Modeling

This article aims to calibrate a gasoline-powered spark ignition (SI) engine using the model-based calibration (MBC) technique for torque control application. MBC methodology has been used to solve the calibration problem more effectively compared to the conventional method. It uses the statistical approach to lower the calibration time and cost. This study described different MBC steps to calibrate a multicylinder SI engine. After that, the calibrated engine parameters were utilized to develop a torque control system using mean value engine modeling (MVEM) in MATLAB Simulink. The analysis showed that the MBC method proved to be effective for generating real-time calibrated maps with a smaller workload and time. Additionally, it helps to enhance the output torque of the engine. While designing a control system, the focus is to achieve accurate transient and steady-state performance over a wide operating range. Thus, two different cylinder airflow calculation-based (speed-density and throttle-flow) techniques were used to develop the engine models for investigation. The simulated results of these two models were compared with the experimental results of the original controller to find an optimal strategy for effective torque control. It was found that the throttle-flow and speed-density methods both offered comparable torque tracking control during load torque variation. However, compared to speed-density, the throttle-flow methodology provided peak tracking error at the initial stages of acceleration and deceleration conditions. The throttle-flow method provided an instant torque response to the acceleration and deceleration conditions. Hence, the throttle-flow approach can be considered for the controller design of high-speed vehicles.