Dct Transmission System Of Agricultural Tractors Study

Big and medium-power tractor is compression technique manufacture in agriculture machine, which is a level to evaluate a country in technique in agriculture machine.Although our country has a great elevation in technique about tractor, but it has a bigger disparity in the world.At the present time,the DCT was widely used in automobile, but was none used in tractor. This paper will put DCT used in auto to tractor based on DCT research,which make power continue output in the shift process,and improve fuel economy.It will improve technique level in big and medium-power tractor our country.Dual clutch transmission which is based on the existent MT, inherits many advantages such as high transmission efficiency, compact package space, light weight and low cost, excellent shift characters and launch etc. Components and product line of manual transmission (MT) which is widely applied in transmission market of our country can be used to design and manufacture DCT, which is in favour of the upgrade from MT to automatic transmission and coincide with the situation of our country. This paper mainly studies on the following aspects, which based on transmission parameters of a specific tractor equipped with DCT.Types,configuration,work principles of DCT and study significance of this dissertation are briefly presented. In addition, the existing state of the starting strategy, shift schedule and optimization strategy of shift quality are detailedly summarized and the development trends are put forward.Dynamic characteristic of DCT during tractor runing are analyzed. The dynamic model of the wet clutch's starting process is built. Analyze the dynamic equation of different phases during the clutch engagement.clutch control strategy in the vehicle start-up process is presented after start-up assessment index and its influence factors are analyzed. Influences of Artificial Neural Network parameters to the accuracy of system identification,based on the experiment data of the engine,are analyzed.Model of the engine are established., Then design the Fuzzy controller of clutch pressure With fuzzy control theory.Dynamic simulation model of DCT powertrain was implemented using the MATLAB/Simulink/Stateflow software. Then simulat the vehicle starting process in different throttle opening by the vehicle powertrain model.The control strategy of clutch engagement and disengagement is analyzed.And the dynamic model of shift process is established and the shift process is simulated.The engaging process of the clutch is analyzed, clutch starting strategy based on fuzzy control which comprehensively considers the driver intention, engine running state and clutch engaging state is presented. Then, control parameters are choosed and control rule is presented.In addition, intelligent compensating shifting schedule using "sugeno"fuzzy methnod is devised, which can avoid shift hunting and can improve fuel economy.