Design Of Quantitative Pump Control System For Water And Fertilizer Irrigation

Water and fertilizer integration technology is to mix water and fertilizer according to a certain proportion and then irrigate,and the function of water and fertilizer one machine is mixed fertilizer.There are many ways to mix fertilizers in the existing water and fertilizer machine,such as: using the pressure system or the natural terrain to transfer the fertilizer,using the opening degree of the valve to adjust the amount of fertilizer,with the help of the fertilizer barrel,the water fertilizer will be mixed in the fertilizer barrel.Mix and then irrigate.At present,most of the mixed fertilizer methods can’t be precisely transported.Which leads to the unreasonable use of chemical fertilizers,and causes a series of problems,such as environmental pollution.For the issue of precision irrigation,this paper has designed a quantitative pump control system.The purpose of the research is to control the quantitative transport of fertilizer in the integration of water and fertilizer,and to control the pump according to the information sent by the host computer.Quantitative pump design modification.The quantitative pump consists of a driving part and a liquid conveying part.This article compares the advantages and disadvantages of several types of motors and pump heads,and then combines the working environment of the system,finally selects the servo motor as the driving source of the quantitative pump,and selects the flexible impeller pump as the quantitative pump fluid delivery section.Finally,a connector was designed and manufactured to connect the two parts together to form a complete quantitative pump.Quantitative pump functional relationships.An experimental platform is designed and built,and a large number of experimental studies on the relationship among quantitative pump characteristics are conducted.The measured data is analyzed by MATLAB software.By comparison of various fitting methods,the three-dimensional surface relationship function among the pressure(MPa),rotation speed(r/min),and flow rate(lb/min)of this quantitative pump is obtained,and the obtained three-dimensional surface map is simplified.The mathematical model expression of the plan is obtained,and the expression of the mathematical model among the pressure(MPa),rotation speed(r/min),and flow rate(lb/min)is approximated by its’ plane figure.And through a large number of repeated experiments,the mathematical model expression parameters are optimized to improve the mathematical model accuracy.Quantitative pump control system design.By analyzing the functional requirements of the quantitative pump control system,the functional design of the control system is performed.The hardware circuit and software program with STM32F103ZET6 microprocessor as the control core are designed,including the minimum system circuit,key circuit,communication circuit,drive circuit and other modules.The system’s control algorithm is designed according to the obtained mathematical model,the system can automatically calculate the parameters value according to the information sent by the host computer,and then controls the operation of the quantitative pump.