The Study Of Modeling And Simulation Of Composed Energy Storage System Of Hybrid Bus

Hybrid electric vehicle has become the most potential way to solve the problem of energy source shortage and environmental pollution which is serious increasingly. The main characteristic of hybrid electric vehicle is much more efficient than traditional vehicle by using two power devices in different modes. The reason why electric vehicles have not been marketing is that the technology of battery has not been broken through. Hybrid electric vehicle which is being developed or has been developed uses battery as its energy storage system, so there are the same problems as electric vehicle, which is not as serious as it. So the technology of battery has become one of the most key technologies which influence the development of hybrid electric vehicles.Battery can reduce dynamic performance of vehicle because of its lower power. On the other hand the life cycle of battery has been shortened greatly during the period when it is charged or discharged in large current. A newly hybrid energy storage system which is composed of battery and ultracapacitor can compensate the shortness of battery. Ultracapacitor has played more and more role on energy storage system as a new storage device. Ultracapacitor has a big power, a small internal resistance and a high efficiency and a long life so that it can afford or accept a large current when vehicle accelerates or brakes. So hybrid energy storage system composed of battery and ultracapacitor can exploit their strength and compensate their weakness.The object of this paper is hybrid energy storage system based on hybrid electric bus XML6112PHEV of Xiamen Golden Dragon Coach Co.Ltd. The insight of the development of hybrid energy storage is shown and the characteristics of energy storage device are analyzed firstly according to a lot of papers. Secondly, adding a new strategy is finished in order to protect battery as soon as possible based on present control strategy of hybrid electric vehicle. At the end of this paper , the components of XML6112PHEV will be designed and simulation will be finished with advisor2002.The results show that ultracapacitor can shield battery from large current greatly and protecting battery and prolonging the life cycle of battery.