The Development of an Electric Bus with Super-Capacitors as Unique Energy Storage

In this paper the development of an electric bus with super-capacitors as unique energy storage is proposed. Super-capacitor has the advantage of quick charge, large power density and long cycle life. The super-capacitor bus is suitable for using in city and the drive distance between two terminals is within 20 km. Its advantage is the capability of frequently start/stop, accelerate and decelerate. Especially, in low temperature the characteristic of super-capacitor is better than that of the chemistry battery. This feature makes it the best choice in the cold area. This project is supported by the government of Heilongjiang province, China. The power of the super-capacitor stacks is 14 kWh, and the voltage range is 160 V-320 V. The maximal speed is 50 km/h. A permanent magnetic motor and a two quadrant IGBT chopper controller are developed. The rating power of the motor is 60 kW and the transient power is 90 kW. Because of the short duration of charging the super-capacitor stacks (about 15 minutes) this kind of electric bus can be used in 24 hours. The performance and the principle details are described in the paper