Study On Control Strategies Towards Power System Of Hybrid Bus

Under the background that global energy decreases and environment problem extrude,every country pays more and more attention to hybrid power automobile.And these vehicles help to improve the efficiency of energy using and decrease the emission of harmful gas,so they hold a higher and higher proportion.In recent years,our country tries her best to promote and popularize hybrid power automobiles,and they play an important role in economy and daily life.Hybrid power carriages are important part of hybrid power automobiles,and they are mainly used in urban area;the traffic situation there has this feature that vehicle run in fixed time and road and idling mode often appears,which is good for hybrid power carriages to save energy and decrease harmful gas.As the performance of a carriage is depend on its strategies,large numbers of people try to research.In this passage,control strategies basing on a domestic hybrid power carriage was studied and the powertrain was also optimized.Then control strategies basing on rule and ECMS are used to research fuel economy as the following:(1)Prototype vehicle performance parameter,key parts parameter are investigated and studied;and then the powertrain was also optimized.The new vehicle is still parallel with one axle,but the key parts are optimized: the engine is YC6J180-42 type instead of the former,the motor is taken placed by Ac induction motor with new parameter,the battery is lithium ion battery with a bigger capacity to improve mixedness level and the speed ratio of main reducing gear and transmission is adapted to meet the requirement of moving.(2)ECMS(Equivalent Consumption Minimization Strategy which is excellent control strategy is chosen for better function;it is analyzed in theory and realizing way and its Simulink model is created.ECMS find the least equivalent consumption with constraint condition while rule-based control strategies changes its model when relevant parameter reach the goal value.(3)The whole vehicle model is created,and the two strategies above are used for simulation.And the simulation results are analyzed.And the whole vehicle model includes vehicle body model,engine model,motor model battery model and transmission model,the optimized goals are consumption and the working condition of circulation is ECE circulation.And then the final optimized goals are compared andanalyzed to promote that ECMS are better strategies.The research starts from practical problem and it can do good to the optimization of prototype vehicle.