The Design Of Plug-in Hybrid City Bus Driving System Based On EMT

With the energy crisis and environment problem getting worse, the use of traditional cars is continuous questioned by energy saving and emission reduction. It is considered that the future of the automobile industry is new energy vehicle, and it will become the most promising industry. In this background, BEV, PHEV, FCEV turn into the hot direction of research and development in auto industry.In this paper, it introduce the supportive policy of new energy vehicle by our government, the construction and development of related basal supporting facility such as charging station, and the present development situation of PHEV at home and abroad. As a result, the opportunity of developing PHEV is coming. Comparing to the ordinary hybrid cars, it gets the advantages of PHEV.Based on the EMT project from Wuhan Tongyu Company of new energy resources, the plug-in hybrid electric city bus is researched and designed. On the basic of existing vehicle WD6100HN, it designs a PHEV driving system with compact arrangement, simple mechanism, reasonable matching and high transmission. With analyzing various kinds of HEV driving system structure, it chooses the single axle parallel hybrid system and RWD drive mode. Besides, the vehicle power system is controlled by HCU, the power coupling between engine and motor is achieved by an automatic clutch.Requested by the design objective, it choose component model of vehicle WD6100HN driving system and match parameters of energy, motor, transmission and storage battery. It uses the self-research EMT system by Automotive School of Wuhan University of Technology. It is an integration of motor and gear box, and it complete shift gears by motor's active speed governing. Referring to current HEV control policies, and combining with the driving system's characteristic of design vehicle, the control policy of transmission's shifting gears and the peculiarity of Chinese typical city bus road condition, it put forward a suitable vehicle control policy. After finishing the initial design, it checks the designing through simulation. In the simulating software ADVISOR, it builds the engine model, motor model, transmission model, storage battery model, vehicle model and control policy model, guides the Chinese typical city bus road condition into the software, inputs each parameter in the operator interface, and finally do the simulation analysis. And then it gets the results of max speed, acceleration performance, climbing performance, the vehicle fuel consumption per hundred kilometers and the working point distribution map of engine and motor. These-results demonstrate that the design reaches design requirements and the whole design is reasonable.