The Improved Design Of Driving System Of Series-parallel Hybrid Electric Bus

The development of the world’s automotive industry has brought great pressureto environment and energy. What’s kind of city bus for the future Low-carbon City?Hybrid Electric Bus (HEB) has become the main development direction of newenergy bus today. The study contents of this paper is based on the driving systemstructure of a Bus Company’s XML6125HEB. For its bad dynamic performance atlow speed, and a new improved design of HEB’s drive system structure with betterdynamic performance and fuel economy is put forward. HEB’s structure arrangement,components selection and parameters design of HEB’s driving system, buildingHEB’s forward simulation model, HEB’s control strategy and simulation studies arecontents of this paper.Firstly, Aiming at a variety of HEV’s drive systems, structure analysis andcomparison of the pros and cons has done. Further, research and analysis of theXML6125-type HEB’s drive system structure and working process is completed, anda new improved design of HEB’s drive system structure is put forward. According tosome old design methods of HEB’s driving system, the components selection andparameters design of the improved design of HEB has been finished.Then, based on this two kinds of HEB’s driving system structure scheme, thistwo kinds of HEB’s whole vehicle forward simulation model are established byapplying the theory of the whole vehicle forward modeling and simulation withMATLAB/SIMULINK software. The two kinds of forward simulation vehicle modelis mainly composed of the various components’ model of each HEB’s driving system.In addition, comparative analysis of different driving system structures of HEB’susual control strategy is worked. The two kinds of HEB’s control strategy areestablished, and HEB’s control strategy models are builded.Finally, based on the two kinds of HEB’s forward simulation vehicle model, asimulation study and analysis of HEB has conducted. According to the operationalfeatures of HEB, several typical driving cycles have been choosed and the two kindsof HEB models’simulation have been carried out under these driving cycles. Thesimulation results indicate that this improved design of HEB not only avoid the mainproblem that the electricity short of its Super Capacitor at low speed happening to the old HEB during its operation, but also has good dynamic performance and economicalfuel consumption. The anticipated improvement design targets are reached.