Intelligent water-saving subsurface irrigation and drainage system

The invention relates to the field of farmland irrigation and water conservancy, in particular to an intelligent water-saving subsurface irrigation and drainage system to overcome the defects that in the existing farmland irrigation technology, the utilization rate of water resources is low, drainage of stagnant water is difficult, and the automation degree is low. The intelligent water-saving subsurface irrigation and drainage system comprises a water supply device, a subsurface irrigation net pipe, a draining device, a control module and a humidity sensing module. The water supply device comprises a water supply pump, a pressure tank and a first solenoid valve X1 used for being connected with the pressure tank and the subsurface irrigation net pipe. The draining device comprises a vacuum pump and a second solenoid valve X2 used for being connected with the subsurface irrigation net pipe and the vacuum pump. The control module comprises a control chip U1, wherein the two output ends of the control chip U1 are connected with the first solenoid valve X1 and the second solenoid valve X2. The humidity sensing module comprises a humidity sensor U2 and two test electrodes J1 and J2, wherein the two test electrodes J1 and J2 are connected with the two input ends of the humidity sensor U2, and the output end of the humidity sensor U2 is connected with the input end of the control chip U1.