Flexible riser monitoring device and control method

The invention relates to a flexible riser monitoring device and a control method. The flexible riser monitoring device comprises a flexible riser, a first valve, a gas-liquid separator, a gas component monitor, a first pressure sensor, a temperature sensor and a liquid collector, the flexible vertical pipe comprises an annular hollow layer; an exhaust hole of the annulus layer is communicated with an inlet of the first valve, and an outlet of the gas component monitor is communicated with the atmospheric environment; the first pressure sensor and the temperature sensor are arranged between the flexible vertical pipe and the first valve in parallel, and the first pressure sensor is used for detecting the pressure of an annular space layer; the liquid collector is communicated with a liquid outlet of the gas-liquid separator, and an inlet of the gas component monitor is communicated with a gas outlet of the gas-liquid separator. According to the invention, the gas-liquid separator is arranged between the first