The Research On Transmission System Parameter Optimization And Shifting Strategy Of Agricultural Truck

The pickup,as an important transportation tool of agricultural products logistics and the modern agriculture development,has it car-ride comfort and certain ability of camping,and it is an important part of agricultural modernization and new rural construction.For the pickup often travels in rural paths,it has to overcome the complex driving conditions.The power affects the whole pickup's transportability characteristic and controllability,the fuel economy has impacts on the cost of farmers and the ability to meet the national fuel consumption requirements;the emissions directly determine the car can reach the national emission standards and whether has the access to production and marketing authorization.In this paper,the power of the pickup truck,fuel economy and emission characteristics are the optimization objectives,it aims to optimize the drive system parameters and shift strategies.Also through the pickup simulation model to analyze the optimization strategies of pickup power,fuel economy and emission.Finally it adopts the comprehensive evaluation system to evaluate all the above strategies.This paper has deeply discussed the method of optimal matching of driveline parameters and evaluated the index of matching also,and the comprehensive evaluation system of vehicle performance is established.Based on the relevant original parameters and experimental data,GT-Drive software is used to build the pickup simulation model,and simulates the mode through statics,dynamics and kinematics.The we compared the simulation results and the original pickup data or official published data to complete the calibration.Also we do simulation calculation of the pickup's drive system parameters.Then through analysis to find the existing problems and causes of the original transmission system,and finally ideas and methods are provided to improve the optimization of the driveline.In this paper,a complete set of method for the optimal matching of the driveline is established,and VBA is used to develop the parameters of the driveline parameter optimization program.Also the program can be based on customer's needs,to do the forward design of the drive system parameters,and the calculation will be more convenient and faster.After the optimization of the transmission system,we further studied the shift strategy,and established the best economic shift strategy mathematical model,and developed the basic principles of the best economic shift strategy.Also use the GT-Drive solution module to get the best economic shift strategy curve;transfer the best economic shift strategy to carry out the vehicle simulation calculation,analyze of the vehicle power,fuel economy and ermissions.And after comparative analysis of the whole pickup's transmission system,we find that the transmission system and shift strategies are optimized.Finally,through the establishment of a comprehensive evaluation system to evaluate the scheme of the original pickup,optimized transmission,and both optimized the transmission system and the shift system comprehensively.And the relevant comprehensive performance evaluation is 0.91,0.95 and 0.98 respectively.The higher the evaluation value is,the better the comprehensive performance of the vehicle is.Therefore,the pickup matching has optimized both the driveline and the optimal shift strategy,and achieved the purpose of optimization.