In recent years

in response to the national call of energy saving and emission reduction

State Grid Corporation of China has organized the work of using SF

6

/N

2

mixed gas for GIS bus

disconnector and earthing switch.A uniform 30%:70% mixing ratio is used in GIS bus

disconnector and earthing switch.Products from multiple manufacturers have passed type tests and technical appraisal of new products

and engineerin

g trials have been carried out in substations.In order to study the operation and maintenance methods of SF

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/N

2

mixed gas GIS equipment

the detection method of SF

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/N

2

mixed gas decomposition products and the characteristic components in the case of equipment failure is studied in this paper.For the decomposition component of N

2

due to abnormal reaction in SF

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/N

2

mixed gas equipment

the gas chromatography analysis method and process are proposed

17 gas components can be analyzed by this method and process.By simulating the defects of partial discharge

abnormal heat and breaking arc of SF

6

/N

2

mixed gas

the characteristic gas components and their variation trend of SF

6

/N

2

mixed gas under partial discharge

abnormal heat and breaking arc are studied

which provide a basis for equipment fault diagnosis and status evaluation.