The Research On Intelligent Control System Of The Combine Driven By Electricity

The combine harvester is playing an increasingly important role in agricultural production. However, the combine harvester of China still exists many problems such as complex manipulation, unreasonable structure of transmission system and great pilot’s labor intensity at present. The design of combines modularly driven by electricity is proposed in the paper. It will make an important contribution for the upgrading of combine harvester and the development of agricultural mechanization in our country.The final purpose of this paper is design the electric scheme and the main control system of combine. For this reason, we extensive research the combine’s structure characteristics, control scheme, control algorithm and the design of the controller. The fuzzy controllers of threshing cylinder and centrifugal fan were designed, and we debugged the simulation model of the threshing cylinder fuzzy control system, the results show that the control algorithm and the fuzzy controller can adjust its control parameters according to conditions, so as to keep the biggest working efficiency. The main research contents, methods and results focus in the work followed.(1) According to the structure characteristics of combine harvester, the paper determined the electric scheme which is 5 modules driven by 7 independent motor. The 5 modules are the header module, the threshing cylinder module, the separation device module, the cleaning device module, the walk system module respectively. According to the various factors that affect the working states of combine harvester and its relationship between each other, the whole control system scheme of combine harvester is determined, and the control schemes of the main parts such as the threshing roller, the reel, the centrifugal fan and the header are also determined.(2) The combine harvester is often difficult to establish accurate mathematical model. Fuzzy control technology is especially applicable to combine who is a complex system. The paper mainly studied control algorithm of the threshing cylinder and centrifugal fan speed, and established the fuzzy controller of the threshing cylinder and the centrifugal fan respectively. And established the fuzzy inference system(Fuzzy Inference System, FIS for short) using MATLAB, the fuzzy controller is feasible through the surface of observer. The established fuzzy control rule can satisfy the requirements of the system.(3) In view of the power consumption model of the axial flow threshing cylinder and wheel speed model, the axial flow threshing cylinder model and wheel speed model is established in Simulink library. The model was encapsulated and created the subsystem of threshing drum and reel. And verify the correctness of the model. Established the fuzzy controller of the threshing drum using Fuzzy Logic Toolbox of Simulink, and the fuzzy controller, subsystems of the threshing drum and reel and other parameters modules were assembled, and completed simulation model of intelligent control system of combine initially.(4) The simulation experiments results show that when crop density changes, the callback time of threshing cylinder rotation speed is 5.0s, the largest deviation is /35.0srad, the steady-state deviation is /03.0-srad and the relative deviation is 0.77%. When crop humidity changes, the callback time of threshing cylinder rotation speed is 6.0s, the largest deviation is /6.0srad, the steady-state deviation is /1.0-srad and the relative deviation is 1.3%. The designed fuzzy control system can meet the requirements of complex combine, and achieved the desired design goals basically.