Four-wheel Drive Vehicle Transmission Efficiency Analysis And Test System Design

In this paper,in the light of the 4WD vehicle transmission efficiency problem,first of all,through to the transmission system’s foundation component power characteristics analysis and theoretical calculation,and based on the MATLAB / Simulink to build simulation model of all drive system components transmission efficiency and vehicle drive system efficiency model.The simulation analysis shows that,under different the condition of the gear speed,the efficiency of the transfer case transmission system efficiency and the efficiency of the whole vehicle transmission system.In addition,design the mechanical system of the 4WD vehicle transmission system comprehensive performance test bench,and based on LabVIEW software written a set of test software of transfer case testing and torque transmission efficiency testing.Finally,the efficiency test data of the key components of the transmission system is obtained through the loading test to verify the model of the transfer case transmission system efficiency model validity is by the experimental data.The concrete research content is as follow:Analysis foundation component of the 4WD vehicle transmission power loss,established each unit mathematical model of power loss.According to the theory of thermodynamics and mechanical principle and other disciplines of professional knowledge,through all of component of the 4WD vehicle transmission system carries on the theoretical analysis,and take advantage of some empirical formulas of dynamic,static and other relevant theoretical knowledge and friction power loss,used MATLAB / Simulink established transmission components mathematical model of power loss of gear meshing、the friction resistance coefficient of the tablet group、bearing friction power loss and other rotating parts wind drag,oil mixing.Finally,set up the all of components transmission efficiency simulation model and the model of vehicle transmission system efficiency,and transmission efficiency of transfer case efficiency and the four-wheel drive transmission efficiency of transfer case carry on simulation.In order to experimental study and analysis of the four-wheel drive vehicle transmission system key parts,the design of the four wheel drive vehicle transmission system simulation test bench.The requirements and scheme of the test bench,the selection of the transmission parts,the connection of the mechanical assembly,the simulation of the front-and-back driving damping,and the control system of the test bed are designed,and completed build the overall platform.In the light of test bench test system,based on LabVIEW development environmentauthorized strength measurement and control software,and combined with the measure and control system based on PXI hardware design test bench,measurement and control system can realize the online data acquisition,monitoring control and off-line data analysis function and so on.Used four-wheel drive transmission system comprehensive test platform,and selected measurement and control system,to the torque transmission efficiency of on a certain timely four-wheel drive transmission system key component transfer case tested..According to transmission efficiency of mechanical transfer case of test method Standard,making transfer case transmission efficiency test scheme,the transmission efficiency of key components of the four-wheel drive vehicles test,and test and analyze and process the experimental data,verify the transfer case power loss theoretical analysis and results of simulation unity,and analysis error.