Hybrid electric city bus Driving cycle Testing and Analysis Based on Data Stream

City bus driving cycle has important role on control strategy of hybrid electric vehicle. A testing system based on data stream function of vehicle electronic control system was developed to test the city bus driving cycle. By measuring such parameters as engine speed, throttle position, vehicle speed and passenger number, statistic results indicated that parking time, vehicle speed, acceleration, deceleration and passenger number accorded with normal school. In all the running time of a city bus, idle speed time account for 25.3 percent, acceleration and deceleration time 69.1 percent, and even speed time account for 5.6 percent only. According to the driving cycle developed, hybrid electric city bus control strategy was optimized. Research results indicated that engine consumed less fuel by such means as engine idle speed cycle limited, using small power engine, improving engine's running state and adopting regenerative braking technique.