The Research Of Variable Fertilization Control System Based On The RBF-PID Algorithm

We invest more fertilizer resources in our traditional agriculture but the utilization rate is relatively low, which causes ecological problems of soil erosion, declining of soil fertility and groundwater contamination etc. Therefore, people need an effective method urgently to improve the utilization of fertilizer and reduce the damage to ecological environment. In this paper, electro-hydraulic proportional variable rate fertilization control system accomplish the research object, which researched on the RBF-PID algorithm to control the effect of variable rate fertilization control system.(1) Determining electro-hydraulic proportion variable fertilization control system, establish electro-hydraulic proportion valve controlled hydraulic motor mathematical model with adoption of mechanism analysis method. Combined with intelligent control theory to explore control strategy of variable rate fertilization control system, in which the rising time for RBF-PID algorithm is 0.05 s, adjusting time is 0.064 s and overshoot is 0.038%.(2) Propose a variable fertilization control system with the cores of PID parameter control software and variable fertilization closed loop controller and make detailed and deep research on two core parts of control system. Explore RBF-PID algorithm module interface with Java Builder component, compile PID parameter control software and propose and solve problems of PID parameter in line tuningof RBF neural network. Make research and development of variable fertilization closed-loop controller with the core of SCM, design precision constant current source, velocity measurement, D/A transfer, serial communication and other circuits and make closed-loop control to shaft speed of fertilizer with adoption of incremental PID algorithm.(3) Make detailed analysis of fertilization accuracy and speed tracking feature of variable rate fertilization control system based on fertilization experiment data. When the shaft speed of fertilizer at 30~120r/min, fertilizer amount and rotating speed change in proportion. Relative error of fertilization amount is less than 3.22%, rising time is less than 1.13 s and overshoot is less than 2.8%, the degree of rotation speed discrete data is relatively small in steady state.This paper analyzes the characteristics of variable fertilization control of RBF-PID algorithm with adoption of theoretical analysis, computer simulation and laboratory test and other methods. Research results show that RBF-PID algorithm has excellent dynamic performance and steady performance, which can adapt to changes of controlled object rapidly and give the optimal combination of PID parameter to improve the fertilization performance of variable fertilization control system and satisfy the requirements of precision agriculture variable fertilization control.