Simulation And Optimization For Powertrain Systerm Design Of Hybrid Cross-country Vehicle

The cross-country car has broad market prospects, Because of Power and safety the use of hybrid technology in off-road vehicle can solve the high consumption and high emission characteristics.Let the dynamic performance and fuel economy achieve optimal, but at present the hybrid power technology more use on the buses and cars,very rarely used in off-road vehicle, I will do some research on hybrid drive system how to use on the cross-country car, the main contents are as follows:(1) Firstly, Researching background and significance for the development of hybrid electric vehicle, the feasibility analysis of using hybrid technology on off-road vehicle, the key technology of hybrid and listing the off-road HEV development condition, proposing research methods and ideas in this paper on the cross-country car.(2) According to the characteristics of the cross-country vehicle-4WD, analysis the layout plan of4WD on SHEV, PHEV and SPHY. Combined with its dynamic as requests, I determined the research of hybrid off-road vehicle driving system structure.. Then I analysis the hybrid vehicle working process, study is based on the engine and battery for the advantages and disadvantages of different control strategies focus,then build SIMULINK diagram, finally to get the control strategy of power off-road vehicle.(3) Combined with the traditional power off-road vehicles, it puts forward a hybrid SUV vehicle parameters and performance indicators, selection of drive system of hybrid electric off-road vehicles and parameters calculation, including the choice of engine power, motor speed power determination, the determination of battery voltage and the determination of the transmission ratio.(4)Choosing hybrid vehicle simulation software, and establishing model of the drive system. To separate modeling of special structure of all-wheel drive SUV, finally to establish good power performance and fuel economy of the vehicle model to do analysis, and compare with conventional power SUV.(5)Using optimization tools to option hybrid sport utility vehicle drive system and control parameters of the system, introduced different optimization methods, and finally choose a simple genetic algorithm as the optimization method in this article, the problem is reduced to a typical nonlinear constrained multi-objective optimization problem, using a weighting factor optimization method, the multi-objective optimization problem into a single objective optimization problem. And before and after optimization parameters and results for analysis shows that the reason for the occurrence of early convergence for analysis.