All SF6 insulated apparatuses face a common problem

i.e.metal particles will be produced inside the GIS or GIL apparatuses in the processes of manufacturing and operation.Under the action of coulomb force in electric field

the particles will move in the apparatuses or adhere to insulators and electrodes to cause breakdown or flashover between inner electrode and enclosure

thus to lower the insulation performance of the equipment.Therefore

it is necessary to set some devices

such as particle trap

to reduce the effect of the metal particles on the insulation performance of the equipment.This paper sums up the researches on weakening the particles’ effect

introduces the patent of Westinghouse Electric Corporation and other relevant patents for deactivating the particles

and analyzes the theoretical bases of these patents by making use of the researches in literature.