Research Of Electro-Hydraulic Hitch System Of Tractor

Tractor is the most important power machinery in agricultural production activities,with a large demand,and its mechanization level largely represents the country’s agricultural level.When tractors participate in many farming activities,the hitch system is a very important component.Compared with the development status of foreign electro-hydraulic hitch systems,there is no mature market product in China and related research is focused on theoretical aspects.As well as the country’s needs and strong support for agricultural mechanization,this article will start the research on the electrohydraulic hitch control system.The main research contents are as follows:In chapter 1,the current product status and theoretical research status of electrohydraulic hitch systems at home and abroad are summarized,and the research content and preliminary schemes of electro-hydraulic hitch systems developed in this paper according to customer needs are formulated.In chapter 2,the working modes of the electro-hydraulic hitch system are introduced,this chapter designs the principle components of the system,the hitch control valve,and performs steady-state performance tests on the valve group to provide reliable data for simulation research.The required sensor selection and circuit principle design of the electronic control unit.In chapter 3,based on the establishment of the system mathematical model,analyzes the system performance of the electro-hydraulic hitch system in the time domain,frequency domain and stability,and analyzes its non-linear characteristics.Then,the comprehensive control mode of the system is analyzed by the AMESim and Simulink joint simulation method;Finally,a variable comprehensive degree coefficient control algorithm based on single neuron PID was proposed to solve the control problem brought by the change of soil specific resistance,and related simulation research was carried out.In chapter 4,an active vibration damping mode based on the electro-hydraulic hitch system is proposed for the transport conditions of the tractor.The system model is built by Simulink.The fuzzy PID controller design is completed using Fuzzy Logic Toolbox of MATLAB.Three different road input models are used.To verify the performance of the active vibration reduction system,evaluate its vibration reduction performance from three aspects of driving comfort.In chapter 5,the hardware equipment for experimental research is introduced,this chapter designs the control panel required for human-computer interaction according to user habits,completes the software design of the electronic control unit based on the hardware conditions,and performs the position control mode of the tractor electrohydraulic hitch system under the existing test conditions.In chapter 6,the progress of the work is summarized and further research directions are pointed out.