Gas replacement method for hydrogen-cooled generator

The invention relates to the technical field of generators, in particular to a gas replacement method for a hydrogen-cooled generator. According to the method, unpurified hydrogen in a hydrogen supply unit is replaced with carbon dioxide, and then the carbon dioxide is replaced with air; guiding the unpurified hydrogen into a hydrogen purification unit, and purifying the unpurified hydrogen to obtain purified hydrogen; replacing air in the hydrogen supply unit with carbon dioxide, and then replacing carbon dioxide in the hydrogen supply unit with purified hydrogen; when carbon dioxide replaces hydrogen, the hydrogen supply unit is heated. The heating temperature is determined according to different carbon dioxide replacement speeds, and the problems that the replacement efficiency of a hydrogen-cooled generator is low and a pipeline is frozen and blocked due to sharp temperature drop in the carbon dioxide gasification process are solved by dynamically adjusting the replacement speed. And by collecting the rep