Modeling and Simulation of Fuel Cell Buses

Abstract

Fuel cell buses are powered by lithium batteries and fuel cells, according to the characteristics of the transmission structure and power source of a particular fuel cell bus, the mathematical models of the longitudinal dynamics, driver, demand torque, motor, fuel cell, and battery have been analyzed and established based on Matlab/Simulink. At the same time, a power-following real-time energy management strategy has been designed. After three sets of China heavy-duty commercial vehicle test cycles for buses and coaches were verified in a combined simulation, the results showed that the model of fuel cell bus better reflects the working characteristics, and the power distribution strategy can keep the fuel cell operating within a high efficiency range as much as possible. The battery provides energy when there is insufficient power, absorbs excess power from the fuel cell, and simultaneously recovers the energy lost from braking. The charging state is also maintained within a certain range. In addition, the hydrogen consumption has a negative correlation with the initial charging state.