Power Distribution Control for a Fuel Cell Hybrid Electric Bus

Under the pressure of air pollution and oil shortage of transportations, hydrogen as a renewable and clean energy gets more and more attentions from all over the world. There predicts that the 21s' century will be a hydrogen century. Nowadays, for the cost and not matured technology of fuel cell stack, hybrid system becomes the best solution. For a 5-ton fuel cell hybrid electric bus discussed in this paper, high-pressure PEMFC and high-power NiMH battery pack forms the hybrid system. In order to obtain the higher fuel efficiency and avoid the frequent charge & discharge of battery pack, a control strategy for the fuel cell-oriented control is proposed. The controlling limitation model for the high-pressure fuel cell engine is built. The control logic to realize the fuel cell as the primary power source and maintain the SOC of battery pack is built. Experimental results indicate that the fuel cell power can follow the driver's requirement very well. The hybrid vehicle's hydrogen consumption is up to 2.464 kgldr(100km)-1 (25.2 mpg).