Test device and test method for measuring change of rock core permeability along with pressure

The invention discloses a test device and a test method for measuring change of rock core permeability along with pressure. The device comprises a hydraulic cylinder, a servo motor, a PLC and a watertank, the water tank is communicated with the hydraulic cylinder through a water inlet pipe, and a water inlet valve is arranged on the water inlet pipe; the upper end of the hydraulic cylinder is communicated with the rock core through a water outlet pipe which is provided with a pressure sensor, a pressure gauge and a water outlet valve; the lower end of the hydraulic cylinder is communicated with the hydraulic cylinder through an emptying pipe, and an air valve is arranged on the emptying pipe; the water inlet valve, the pressure sensor, the water outlet valve and the air valve are all connected with the PLC; the PLC is connected with the servo motor, and the servo motor is connected with a piston rod of the hydraulic cylinder through a reduction gear pair and used for driving the piston to move up and down. Te