Liquid level-pressure coordinated control method used for gas-liquid separator

The invention relates to a liquid level-pressure coordinated control method used for a gas-liquid separator, used to set a liquid level-pressure coordinated control device. The method comprises: presetting each target value and opening initial values; determining whether gas-phase pressure is larger than a preset gas-phase pressure target value, calculating a valve opening value of a first pneumatic control valve and feeding back to a valve to operate; determining the relations between the difference value of the maximum value and the minimum value of pressure measuring values and pressure fluctuation errors; determining whether liquid level measuring values are larger than a preset liquid level height target value, calculating the valve opening value of a second pneumatic control valve and feeding back to a valve to operate; determining relations between the difference value of the maximum value and the minimum value of liquid level measuring values and liquid level fluctuation errors; performing simple control on gas-phase pressure and liquid level height in the gas-liquid separator; determining received liquid level height; and a liquid level-pressure operation control module determining whether the received gas-phase pressure exceeds an error range, and determining whether the received liquid level height exceeds an error range.