Electric field relaxation effect of Functionally Graded Materials (FGM) with conductive multilayer coating

For the insulation design of gas insulated power apparatus, the electric field grading and control are indispensable. We have proposed the application of σ-FGM (Functionally Graded Materials with spatial distribution of conductivity σ) to solid insulators as a novel technique of the electric field grading and control. In this paper, we fabricated the conductive multilayer coating for σ-FGM and investigated the electric field relaxation effect of σ-FGM on a GIS spacer surface. The fabrication results revealed that we could obtain the conductive 3-layer coating by using the dip coating method. The calculation results revealed the technical feasibility of electric field relaxation by σ-FGM with the conductive multilayer coating.