The present application belongs to the field of
direct current transmission, and particularly relates to a support insulator, an insulating support structure and a
direct current GIL. In order to solve the technical problem that the
electric field lines pass through the support insulator in the prior art, resulting in that the
normal field intensity of the side surface of the support insulator is too large, the present application provides a support insulator, which comprises a high-potential
support surface for supporting a conductive rod, a low-potential
support surface for supporting an insulating cylinder and a side surface, the high-potential
support surface and the low-potential support surface are both arc surfaces, the axis of the high-potential support surface and the low-potential support surface corresponds to the axis of the matched conductive rod, and the extension line of the projection of the side surface of the support insulator in the direction of the axis of the corresponding conductive rod intersects with the axis of the conductive rod. The present application further provides an insulating support structure and a
direct current GIL using the support insulator. By making the
electric field lines parallel to the side surface of the support insulator, the
normal field intensity of the side surface of the support insulator can be reduced, and the surface
flashover voltage and the insulating strength of the support insulator can be improved.