Computer Simulation of an Electric Trolley Bus

摘要

This report describes a computer model developed at the Transportation Systems Center (TSC) to simulate power/propulsion characteristics of an urban trolley bus. The work conducted in this area is sponsored by the Urban Mass Transportation Administration as part of a larger effort concerned with the demonstration and test evaluation of advanced bus propulsion concepts. The computer models developed by TSC provide a means of rapidly evaluating bus performance and of comparing simulated bus performance with results obtained from engineering tests. They also provide a means of developing comparative information of the performance characteristics and component sizing requirements of various bus propulsion systems. The results of the computer analyses will be incorporated into the Annual Technological Assessment Report for future reference and evaluation. This present report includes a description of the application of the trolley bus model to a typical urban bus drive cycle. The requested mission profile is given as input to the bus model while the actual mission profile determined by the limitation of the bus propulsion system appears as output. The output data file also lists the electrical drive characteristics, including component power losses, at successive intervals of drive time. The report describes the computer simulation of an electric trolley bus as it traverses an arbitrary mission profile of specified acceleration, roadway grade, and headwind. The models for the different bus components are examined and the impact of cam-control on trolley bus performance is reviewed. The simulation model is used to generate power-propulsion characteristics for a trolley bus operating over different urban drive cycles. Program listings, including a CALCOMP subroutine for graphic display, are presented in the Appendix.