Systematic design and power management of a novel parallel hybrid electric powertrain for heavy-duty vehicles

A novel multi-degree-of-freedom parallel hybrid propulsion system with multi-gear for heavy-duty vehicles is proposed to optimize fuel economy, driving comfort, and dynamic performance. The system has a compact structure and high integration. The detailed design and the power flow of the parallel hybrid propulsion system are introduced. The full power system prototype is designed and assembled. The control methods for the driving torque compensation and energy management are investigated. The simulated results of the parallel hybrid propulsion system are presented. The propulsion system power is not interrupted during gear shifting with the torque compensation control. The jerk of the vehicle is also reduced during shifting. The internal combustion engine can work more efficiently in the hybrid propulsion mode with the equivalent consumption minimization strategy. The purpose of this paper is to provide a hybrid driving scheme for commercial vehicles.