The transient electric field analysis applying to HVDC SF/sub 6/ insulation design

The problem of electric field calculation applied to the internal insulation of HVDC SF/sub 6/ power apparatus is considered in this paper. The transient electric field model and calculation method, taking account of both surface and volume conduction parameters, is presented. The electric field for the basic SF/sub 6/ GIS configurations in both operating conditions: long-term HVDC application; and rapid polarity reversal (RPR) of DC voltage, are considered. Principal patterns and peculiarities of the transitory electric field distribution along the spacer surface are analyzed. An engineering approach and recommendations to HVDC SF/sub 6/ insulation design are substantiated.