Modeling and design of hybrid control system for dual hybrid electric vehicle drivetrains

This paper describes the modeling of dual hybrid electric vehicle drivetrain and proposes a hybrid control system for controlling the drivetrains. In dual hybrid electric drivetrains, the energy from the engine passes through the planetary gear set and is split into the generator and motor paths. A complete dual hybrid electric drivetrain system model is developed. The modeling process is discussed for each of the major components of dual hybrid electric drivetrain, such as planetary gear transmission, gasoline engine, motor, generator and vehicle dynamics. Integrated nonlinear model and effects of parameter variations are also studied. The hybrid control system which is a discrete-event system interacting with a continuous-state system, is suitable for modeling and control of the systems that have state jumps and dynamics changes. In this paper, on/off state of engine is treated as a discrete state of HEV system and, velocities and torques, etc., as continuous states. The proposed hybrid control system consists of a continuous-state plant to be controlled, a continuous-state controller, an interface, and discrete-state controller. Simulation results are also presented comparing the performance of the proposed hybrid control system with that of the conventional HEV controller.