POWER FREQUENCY ELECTRIC AND MAGNETIC-FIELDS FROM A 230 KV GAS-INSULATED SUBSTRACTION

Gas-insulated substations (GIS) , owing to their compact nature, offer an attractive alternative to conventional substations where space is limited, such as in urban areas. Consequently, it is important to addr ess the issue of environmental conditions in and around the GIS. This paper presents the results of a survey of power-frequency electric and magnetic fields in and around a 230 kV/28 kV GIS. The survey was desi gned to cover the electric and magnetic fields from the substation equ ipment and from the power lines and cables surrounding the substation. It also includes a determination of the shielding effect of the GIS b us sheath. The information provided should allow the prediction of ele ctric and magnetic field levels from other GIS of similar design.