Integrated Design And Simulation Study Of Electric Bus Wheel-Rim Drive System

At present, new energy vehicles have become the focus on the development of strategic emerging industries in our country. The city bus plays a special position in the urban traffic, makes the pure electric city bus become the focus of the new energy automotive research direction. Wide channel and low floor bus because of its advantages such as large capacity, high liquidity of passengers, easily going on and down, becomes the development direction of new harmonious city bus. However, the traditional centralized drive bus has to keep the main reducer and differential mechanism, which makes it hardly to realize low floor. If the wheel-rim drive system can be used in the city bus, its unique decorate form can help to reduce the floor height, broaden the channel width and improve the level of city bus. But this system also has disadvantages like overlarge unsprung mass and hardly being sealed, which will bring ride comfort difficult challenges to the city bus.In this dissertation, focusing on the specialty of the city bus, I analysed and researched a set of reasonable wheel-rim drive system used on city bus, studied the braking energy recovery of this system, and built the whole car’s simulation model including this system in AMESim and did the simulation study. This dissertation’s main research content is as follows:Firstly, I summarized and analysed the advantages and disadvantages of different kinds of wheel-rim drive system, comparative analysed the similarities and differences of the wheel-rim drive system used in different vehicles, to absorb the advantages and avoid the disadvantages, I put forward a set of wheel-rim drive system with two levels of reducer, which includes a fixed axis type reducer and a planetary gear reducer. Secondly, by the public 12-meter bus, according to the scheme proposed in this paper, I designed the wheel-rim drive system’s each reducer’s ratio and other parameters in detail at all levels by the vehicle dynamics. Thirdly, focusing on the differences between traditional centralized drive system and wheel-rim drive system, I studied the braking energy recycling proces. Finally, I built the whole car simulation model including this wheel-rim drive system in AMESim, under several specific working conditions, studied the simulation study on the car body’s and driving wheel’s kinematics performances.