Device and method for guiding out harmful gas at tower bottom of offshore wind generating set

The invention provides a device and method for guiding out harmful gas at the tower bottom of an offshore wind generating set. The device comprises a gas discharge unit, a data processing unit, a first control unit, a gas detection unit, a second control unit and a start-stop detection unit, wherein the first control unit is used for logic control, and is used for controlling the gas discharge unit to circularly and intermittently start and stop based on the theoretical operation duration and the theoretical standby duration calculated by the data processing unit, and the second control unit adopts feedback control, and judges whether to intervene in the logic control of the first control unit based on the detection result of the gas detection unit. According to the invention, discharge of harmful gas at the tower bottom is achieved through logic control, feedback control and gas export while discharge of harmful gas at the tower bottom can be guaranteed through a back-up power source under the condition that