Automatic control method of plunger gas-lift liquid drainage production of oil-gas well

The invention discloses an automatic control method of plunger gas-lift liquid drainage production of an oil-gas well. The automatic control method includes that a buffering clamping and fixing device and a plunger are lowered into an oil pipe after drifting, a gas production tree of the oil-gas well is connected with a blowout preventing pipe, a pneumatic membrane valve is arranged between a ground pipeline and the blowout preventing pipe and electrically connected with a plunger controller, the plunger controller realizes opening and closing of the gas well by controlling opening and closing of the pneumatic membrane valve, and a pressure sensor is arranged in a wellhead gas production chamber and electrically connected with the plunger controller; a casing pressure value when the plunger controller controls the oil-gas well to be open is set, a casing pressure value when the plunger controller controls the oil-gas well to be closed is set, the plunger controller receives casing pressure value signals measured by the pressure sensor, and opening and closing of the oil-gas well are controlled according to set well opening and closing conditions of the oil-gas well. Well opening or well closing of the oil-gas well is controlled according to changing circumstance of wellhead casing pressure and oil pressure of the oil-gas well, the changing circumstance is closely combined with liquid accumulating circumstance of the oil-gas well, optimal liquid lift quantity is guaranteed, and automated control management of the process of plunger gas-lift liquid drainage gas production is realized.