Capabilities Studies Of Nonelectrical Power Control Unit Which Used In Automatic Water Valves

Shortage of water resources has become a serious problem facing the world.At present,the domestic water-saving irrigation equipment is generally low degree of automation;water-saving irrigation equipment from abroad are able to achieve the level of automation,but higher costs. Automatic water-saving valve without electrical power control is a highly automated,low-cost and automatic control equipment,which solve the problems of water-saving irrigation equipment at home and abroad.No power control unit is the core of the automatic water-saving valve without electrical power control,study its performance is the key to the success of water-saving valve.In this paper,the main contents of the study and conclusions are as follows:1.Choice of steel mesh layers in control unit:from the experimental results of three materials in the control unit which made by a layer of steel mesh and two layers of steel mesh,we can see that the steel mesh layers has little impact on the permeable of the control unit,thus taking from the life and stability select the control unit which made by two layers of steel mesh.2.Choice of humidity materials in control unit:from the experimental study for dynamic capabilities of control unit,we can see that dynamic capabilitie of humidity material which mixed by aquasorb,wood fiber and black fungu as 1:5:5 is instability,from the simulation experiment in the greenhouse in the greenhouse we can see that humidity material which mixed by Aquasorb and gravel as 1:3 can not sensitive and automatically switches in accordance with changes in soil moisture.Only the valve with humidity material which mixed by Aquasorb and gravel as 1:5 can controll soil moisture within the framework of appropriate,so a more suitable humidity material in the control unit is the humidity material which mixed by aquasorb and gravel as 1:5.3.Choice of coefficient of spring stiffness in the control unit:in the greenhouse experiment we find that the greater spring coefficient of the steel,the later the timing of cessation of irrigation and beginning of irrigation,even when soil moisture is very low,still unable to start irrigation.This shows that the coefficient of spring steel in the control unit should not be too greater,coefficient of steel is benefit between 0.5N /mm - 2N / mm,estimated by the four springs selected in this paper.4.The establishment of the regression equation:in this paper,we establish the regression equation of soil moisture and the distance between the valve of the three valve successful experiments,this can be applied to facilitate future.In summary,this paper achieve automatically opening and closing of water-saving valve without electrical power control through the study of the performance of control unit,break the traditional idea of using manually or computer,sensors to achieve automatic control,cost savings,reduce labor, and energy-efficient,easy to universal,provide an effective line of thought for future research to automatic irrigation equipment.