MODELING AND SIMULATION OF THE DRIVETRAIN FOR FUEL CELL CITY BUS

摘要

Air pollution mainly caused by emission of hundreds of vehicles in city makes people look after various solutions. Fuel cell electric vehicle (FCEV), as a zero-emission vehicle, shows great potential to alleviate air pollution and reduce energy consumption. So it is necessary to develop FCEV, especially the fuel cell city bus (FCCB) which is an important urban public vehicle. FCCB program, as a part of the state "863" key project, will directly serves for the 2008 Beijing Olympic Games. FCCB adopts the series drivetrain which contains fuel cell system, DC/DC converter, battery packs, induction motor and its controller, transmission, final drive, as well as selectable ultra capacitor units. Most components of the drivetrain are controlled by the vehicle control unit (VCU) through CAN bus. Some difficulties such as the nonlinearity of components especially like the batteries, the strong coupling between separately components and the variety of the parameters etc. challenge us to develop the drivetrain model. In this paper, we will discuss the drivetrain performance of FCCB through computer simulation with Matlab& Simulink. Firstly, each component model of the drivetrain are described, especially the fuel cell system, battery packs and electric drive system for their essentiality in the drivetrain. Secondly, a forward-looking simulation program for drive train is described, with analysis of modeling process, applicability of different models, and simulation results. Finally, Validity of simulation is discussed through experiment results which come from dynamometer test and the operation test of a prototype of FCCB.