Control And Parameter Matching For Dual Planetary Hydraulic Hybrid Drive System

As an important branch of new energy vehicles, Hydraulic hybrid technology not onlycould take the effect of energy-saving and emission reduction like gasoline-electric hybridvehicles, but also avoided the problem of battery that the short life, relatively unsafe workand pollution arising from the post-processing. Nowadays, the parallel and series hydraulichybrid buses and transport trucks have come out domestically and abroad. But thepower-split hydraulic hybrid system still stays at the stage of research and development. Andthis paper is about the power-split hydraulic hybrid configuration.Dual planetary hydraulic hybrid vehicle is driven by both the traditional internalcombustion engine and hydraulic pump/motor. It possesses full advantage of dual planetarygear mechanism characteristics and optimizes force distribution of three kinds of powersources, thereby improving the efficiency of the whole drive system, achieving the purposeof fuel saving and improving the power performance. In order to research on a new type ofenergy-saving hydraulic hybrid system, this paper combines the advantages of hydraulicdrive system and the coupling characteristics of planetary gear, and then studies onparameter matching and power train control of the hybrid system.First of all, this paper introduces and analyses the research development of hydraulichybrid vehicle, instructions the research significance of hydraulic hybrid system, whichconfirms the feasibility of the application of the vehicle.Second, the paper analyzes hydraulic hybrid system architectural and describs themathematical model of the power parts detailly, and then builds a physical model of thevehicle on the software platform of AMESim. After that, according to the subject of thisarticle and the characteristics of the selected configuration, on the premise of the selectedcycling conditions, the paper comes up with a method of parameter matching to ensuredynamic and in the target of best fuel economy. Accordance with the matching method, the paper matches parameters of every the power parts, and at last chooses the power trainconfiguration based on actual product parameters.Again, for the determined characteristics of the dynamic driving and the hydraulic drivesystem, the paper compares the respectively advantages and disadvantages between the logicthreshold control strategy and the engine optimal working curve control strategy. With theadvantages of both strategies, the paper developed logic threshold control strategy based onthe engine optimal work curve. At last, the paper developed control strategy model on thesoftware platform of the MATLAB/Simulink.Finally, on the basis of above study, with the application software of AMESim andMATLAB/Simulink, this paper realize an off-line co-simulation of the whole vehicle model.Through analyzing the simulation results, the paper can conclude that the vehicle's powerperformance meets the request of design and mission, and the energy-saving is better thanthe design goals, which verify the rationality of the system model, matching, selection andcontrol strategy of the hybrid system.In this article, the study which is about control strategy and parameter matching ofhydraulic hybrid system can provide guidance for the follow-up real-time simulationexperiment, power train configuration experiment and vehicle design, can provide theoreticalbasis for study on the key technology of hydraulic hybrid vehicles. The purpose of this paperis to promote hydraulic hybrid technology and to make the hydraulic hybrid technologyapplied to daily traffic system as soon as possible.