| 摘要 |
<p>PURPOSE:To lessen voltage drop on the grounding lead of a lightning arrester and a grounding mesh as much as practicable. CONSTITUTION:A bus bar 11 of a gas insulated apparatus (GIS) is installed in a bus bar tank 13 in which SF6 gas 12 is encapsulated. A lightning arrester tank 16 is mounted on this bus bar tank 13, and an arrester element 17 is provided in the arrester tank 16. An arrester grounding lead 18 is connected with a grounding mesh 15, and a bushing 19 is set between the arrester grounding lead 18 and arrester tank 16 to generate insulation therebetween. A protection device 20 for lessening an influence of transient voltage appearing on the arrester grounding lead 18 and grounding mesh 15 is installed between the arrester grounding lead 18 and the arrester tank 16. This protection device 20 is formed, concretely described, for example from a non-linear resistant element which presents a high resistance in the large current region and a low resistance in the small current region. This accomplishes suppressing impression of over-voltage between the bus bar 11 and the main circuit insulation of bus bar tank 13 even in the event of flowing of a steep discharge current.</p> |
