Supercapacitor Bus Hybrid Traction System Parameters Design And Control

After years of development,the performance of vehicle-used supercapacitors has been greatly improved,with advantages of low internal resistance,high working efficiency,low pollution,and long cycle life,which is particularly suitable for the urban conditions of hybrid electric buses.At present,the battery life cycle cannot meet the operation requirements of the whole vehicle.Domestic mainstream bus enterprises sell the composite power supply(supercapacitor-battery)scheme as the mainstream product even though our country has no financial subsidy policy for the ultracapacitors.There is no doubt about the recognition of performances of supercapacitor in the bus industry.Relying on the bus platform of hybrid power system,supercapacitor is selected as the only energy storage device,and the following work is mainly carried out:1.Determine the type selection scheme of supercapacitors.The performance parameters of supercapacitors are matched according to the technical requirements of the powertrain driving motor and the electric accessories.2.According to the actual vehicle require power and relevant information collected from the trial operation of the hybrid electric bus in different cities,a power database of the vehicle demand power under cyclic operating conditions was established,and the digital characteristics and distribution rules of the vehicle demand power were analyzed by using the statistical probability distribution theory.3.The contact relationship between the high efficiency zone of the engine and motor and the common operating conditions,and the relation between it and the fuel economy are both derived.The technical requirements for the engine,motor and generator with the supercapacitor as the only energy storage are put forward.4.The experimental sample vehicle was modified,and the control strategy of the supercapacitor vehicle was developed at the same time,which improved the instantaneous efficiency of the engine and motor,and completed the local optimization of control parameters.The fuel consumption of typical urban cycle test was 21.44 l /100 km,which decreased 38.5 percent compared with the conventional vehicle.5.Promoted in domestic bus company,completed several sample car tests,and prepared well for market operation!...