Optimization Matching And Simulation Analysis Of The Driveline For A Heavy-duty Hybrid Electric Vehicle

Hybrid electric vehicle combines the advantages of conventional vehicles and pure electric vehicles. Hybrid electric vehicle is becoming more practical and advanced vehicle, for its low power consumption and long driving range. The research and development of hybrid electric vehicle is the most effective and feasible way to achieve the industrialization of energy-efficient automobiles at present. Many domestic automobile manufacturers and research institutions have been dedicating to the research of hybrid electric technology, however the development of heavy-duty hybrid electric vehicles are still in the infant stage. It can be predicted that the development of heavy-duty hybrid electric vehicles will be the direction of hybrid technology, which is also in line with the state policy about new energy vehicles. Heavy-duty vehicles demand high performance, because of their poor working conditions and heavy load. In particular, the heavy-duty hybrid electric vehicle researched in this paper assumes the urban sanitation functions. It has the characteristic of frequent start and stop, heavy load, small running range and the demands of high efficiency and low emissions, which is a challenge for the design of the driveline.Based on the technical information of the prototype vehicle provided by the manufacturers, the dynamic and fuel economy of the prototype vehicle was calculated by MATLAB program. Various performance curves and critical parameters were obtained and compared with the test value, and the feasibility of simulation with the correlation model was proved.Various literature related to the design of hybrid electric vehicle driveline were studied. Trough the contrast and analysis about driveline coupling means, including torque coupling, speed coupling and torque/speed coupling integration, the means of torque coupling and torque/speed coupling integration were selected, and the specific driveline structure was designed.Then according to the selection principle that engine meets basic load demand and the motor meets peak load demand, the power and transmission units of the two programs were selected. And through simulation and verification, the dynamic performance achieved the level of prototype vehicle, which is the foundation of rear calculation for the fuel economy.Two typical control strategies were introduced, and they were integrated to form the control strategy of torque coupling program. Through the analysis of work patterns for the integration program, the control strategy was established, which were the basis of fuel economy calculation that based on the drive cycle.Finally, the performance of hybrid electric vehicle was calculated, and energy consumption level of two programs were obtained. Through the analysis, the energy consumption level of hybrid electric vehicle was proved. And the differences of driveline structure and hybridization degree were considered as the cause of dissimilarity for the energy conservation level of the two programs.