The Research On Parallel Hydraulic Hybrid Hydraulic System Dynamic

In this paper, the main research object is the hydraulic system of hydraulichybrid vehicles, except the hydraulic system to more fully absorb the kinetic energygenerated when the vehicle brake, study and analyze the energy recovery during thevehicle braking process, so as to achieve the purpose of vehicle energy saving andenvironment protection.Based on the analysis of main components of hydraulic hybrid vehicle, selectthe parallel structure as the main research object, and determine the main componentof system. Study and analyze each component work of the parallel hydraulic hybridvehicle energy recovery process. Through the comparative analyzing each controlstrategies of hydraulic hybrid vehicle, determine the hydraulic auxiliary controlstrategy. On the basis of the hydraulic energy recovery working principle, considerthe nonlinear factors in the hydraulic system, determine the dynamic characteristicsof hydraulic system energy recovery process. Make contrast on the common methodused in system dynamic modeling. Power bond graph can well represent power flowof the system in the dynamic process, help to understand physical significance, bebeneficial to correct analysis, avoid mistake; and also deduce the correspondingmathematical model with the power bond graph of system. Establish the dynamicmodel and equation of state model of hydraulic system energy recovery with themethod of power bond graph. Based on the evaluation of hydraulic energy recoveryefficiency, use MATLAB software to simulate the dynamic characteristics in theprocess of hydraulic system recycling energy, analyze parameters of the maincomponents of hydraulic system that affect the energy recovery efficiency whenvehicle brakes according to the simulation results, reflect the characteristics andadvantages of power bond graph used in system dynamic characteristics analysis.