The Design Of Decision-making And Control System Of Orchard Irrigation And Fertilization Based On PLC

At present,the technology of orchard irrigation and fertilization in China has been developed to a certain extent,and its advantages of water saving,fertilizer saving and high efficiency are obviously better than the traditional furrow irrigation,flood irrigation,artificial fertilization and furrow fertilization.However,the decision-making and control system of irrigation and fertilization equipment in China is still not perfect,and the applicability and stability problems have not been effectively solved,so it is very important to develop the decision-making and control system.The decision-making and control system of orchard irrigation and fertilization based on PLC designed in this paper takes Siemens S7-200 smart PLC as the control core of the lower computer,and the upper computer is composed of the cloud platform provided by the powerful technology QDGate301-L PLC remote control module and Siemens smart 700 IE V3 human-computer interactive touch screen,which realizes the stable control of orchard irrigation and fertilization.The system deployed soil sensor,fruit tree canopy environment temperature and humidity sensor,fruit tree leaf surface temperature and humidity sensor and meteorological station to obtain orchard information,and makes water and fertilizer decision-making scheme based on variable universe fuzzy decision-making method of adaptive weighted fusion algorithm.When the system works,according to the level sensor,pressure sensor and other sensors to obtain the real-time working status of the equipment,control the operation of the actuator.The research content of this paper is as follows:(1)Using Siemens S7-200 smart PLC built the information monitoring system of the decision-making and control system of orchard irrigation and fertilization.Six soil monitoring nodes were deployed in the orchard soil to collect the soil temperature and humidity,EC value and pH value in the way of square partition node deployment;two fruit nodes were deployed in the orchard in the way of random deployment to collect the canopy environment temperature and humidity and leaf surface temperature and humidity;one was deployed inside the orchard boundary The meteorological station realizes the real-time monitoring of orchard soil,fruit trees and meteorological information,and provides data support for the decision-making of water and fertilizer.(2)The control and execution system of orchard irrigation and fertilization decision-making and control system is developed by using Siemens S7-200 smart PLC,including irrigation water filtration and backwash subsystem,irrigation subsystem,fertilizer mixing subsystem,fertilization subsystem and pipeline valve control subsystem.Through the liquid level sensor,pressure sensor,liquid EC value sensor,pH value sensor and differential pressure switch to obtain the real-time working state of the system,the automatic operation of the orchard water and fertilizer equipment is realized.(3)The cloud platform provided by the powerful technology QDGate301-L PLC remote control module and Siemens smart 700 IE V3 human-computer interactive touch screen are used to complete the development of the monitoring platform,which realizes the orchard water and fertilizer information query,irrigation and fertilizer control and equipment status query,and provides the user with intuitive and simple human-computer interactive control.(4)The fuzzy decision-making method of variable universe based on adaptive weighted fusion algorithm is used to determine the decision-making of irrigation and fertilization.The fuzzy rules of double input and single output are established respectively by using the optimal soil moisture offset value and orchard temperature(average values of the fusion values of soil temperature,canopy environment temperature and leaf surface temperature),soil EC offset value and soil pH offset value The decision-making scheme of irrigation and fertilization was obtained.The decision-making and control system is stable,easy to operate,simple interface,expandable,can adapt to the operation of orchard irrigation and fertilization equipment,and has broad application prospects.