Research On Intelligent Control System Of Plot Grain Combine Harvester

Seed is the most basic means of production in agricultural production,which contributes 30%to the increase of agricultural production in China.Cultivation of improved varieties requires field breeding experiments.Grain seed harvesting in breeding plots is the final link of field breeding experiments.Harvesting quality and efficiency directly affect the accuracy of experimental results and the breeding of good varieties.The use of plot combine harvester effectively improves the efficiency of plot harvesting operation and reduces seed loss.However,because of the different planting conditions in each experimental plot,the working status of the harvester in the plot will change with the different experimental plots.If the parameters of the harvester can not be adjusted in time,it will lead to the failure of the harvester in the plot,affect the harvesting quality and efficiency,and even lead to the blockage of threshing drum or other working parts and damage the machine.It is necessary to design an intelligent control system for grain harvesting equipment to adjust its operation speed according to different working conditions in different plots so as to make it in the best working state.In this paper,the intelligent control system of high-purity grain harvesting equipment is studied with rice-wheat and maize combine harvester in plot as the research object.The main research contents are as follows:?1?Based on the analysis of the operation process of the rice-wheat and corn combine harvesters in the residential area,the functions required by the control system are determined:pre-alarm of blocking failure,real-time online control of operation speed;Through analyzing the influence of each working part on the harvest quality of the grain combine harvester in the plot,the monitoring object and input and output parameters of the system are determined,and the overall scheme design of the system is carried out.According to the system design principles and system design requirements,the system hardware equipment is selected.?2?The design of regulation and control scheme and pre-alarm scheme of the regulation and control system is carried out,a system blockage fault diagnosis method is proposed,and a pre-alarm judgment rule is established;The control process of the working speed of the walking system of the plot grain combine harvester is analyzed,the mathematical model of the valve-controlled hydraulic servo system is established,and the transfer function of the rotating speed₈)of the hydraulic motor of the servo system to the input voltageis determined.Based on this,the fuzzy PID controller of the working speed is designed,the fuzzy control rule table is established,and the fuzzy PID is simulated by Simulink.A fuzzy controller for threshing cylinder speed-expected working speed is designed.The experimental data of threshing cylinder in document[45]is used as the input signal of the simulation model,and the fuzzy PID working speed control algorithm is verified by simulation experiments.The simulation test of the regulation algorithm under the disturbance signal of different amplitude pulse signals is carried out to further analyze the dynamic response performance of the regulation algorithm and evaluate the effectiveness of the algorithm.?3?Software and hardware design of control system.Configure specific parameters of hardware equipment protocol converter,S7-1200 PLC CPU module,communication module,analog I/O module and touch screen;Design S7-1200 PLC software program,mainly including engine message analysis program,jam fault pre-alarm rule program and fuzzy PID control algorithm program;Design touch screen interface program,mainly including pre-alarm monitoring interface,parameter setting interface and rotational speed data storage design,touch screen system and safety protection design of key components;?4?Taking 4YWZ-1.0 plot corn combine harvester as an object,the system performance test was carried out to verify the correctness of the prediction and alarm rules of the working parts.