The Study Of Mix And Irrigate Control System Of Soilless Culture Nutrient Liquid

The technology of soilless culture is a new kind of agricultural technology that can culture crops without soil but by nutrient liquid. It is a great innovation in human plant method. It has developed quickly around the world because of its high-speed grow, good harvest and high quality. With development and synthetical application of modern agriculture ^ computer and environment control, it has grown up an agricultural technical system. Its development can bring important renovation to agriculture technical content and effect of production. In our country the soilless culture technology starts recently, so it is in underway and experimental phrase now. To fit the situation of our country we should develop the technology with easy operation, cheap cost and good effect. Mix and irrigation are keys of the technology. Mix nutrient needs specific control equipment that almost introduced from overseas nowadays. Therefore this paper has studied the system of nutrient liquid mix and irrigation for the purpose of replacement of overseas machine. This paper introduces the main adjustable parameter and theory project, and designs technical flame based on the project theory. Aimed at the system functional character, this paper studies the control system with quick response > easy operation and stability.The main adjustable parameter about control nutrient liquid is ionic consistence and acid. Electrical conduction varies with ionic liquid, so it can reflect the ionic of liquid. pH reflects the acid of liquid. So this paper expatiates on measure theory of EC and pH, and makes certain measure methods of EC and pH. Though finding answer by the theory of "black box", this paper selects the functional cell and drive mode. In the detailed design of mix and irrigation of nutrient liquid based on functional command this paper makes sure the performance parameter of main control system and introduces design of measure circuit and the selection of execute framework. As a while, this paper provides the control system theory overall graph. The paper analysis and makes sure the whole system's running project. At last the paper provides main program flow chart and introduces timing intermit module ^ data processing and real-time clock module designed by modules.The result of measure circuit stability test and coupling test suggests that the control system can reach the request of precision and finish control command of automatic mixingand irrigation.The method of design and test in this paper is aim at soilless culture mixing and irrigation control system. The theory and basic idea of this method is also fit for design and exploitation of other mechanic-electric system.