Reverse Dynamic Optimization of Variable Displacement Engine Operation and System Integration

Variable displacement engines are a proven technology for improving fuel economy without sacrificing performance. To achieve the most benefit, variable displacement needs to be properly integrated into the vehicle system. A reverse tractive road load demand model, dynamic optimization methodology, and Matlab®/Simulink® based tool are developed to address the challenge of properly matching variable displacement engines and their control strategies to specific vehicle applications for improved overall vehicle system efficiency. Using a reverse model and a dynamic programming algorithm, optimal variable displacement control strategies considering the gear shift and torque converter clutch interaction effects for various drive cycles are developed virtually. The development of an optimal control strategy facilitates better integration of variable displacement into vehicle system designs.