Abstract: A power transformer is provided with a housing having a plurality of apertures for receipt of a bushing well of a bushing assembly. Each bushing assembly includes a bushing well adapted to be secured in one aperture of the power transformer, and a bushing adapted to be connected to a terminal in the bushing well to permit the conducting of electric current between the bushing assembly and the transformer. The bushing assembly further includes a connector for connecting the bushing conductor to a terminal positioned in the bushing well. The power transformer may include a cap to cap the unused bushing wells. The cap is, preferably, a plate structure that attaches to the lip of the bushing well and uses the dielectric formed by the air enclosed by the cap and the bushing well to prevent sparking over to adjacent sites and corona discharge, to prevent accidental contact with the live terminal therein, and to guard against contamination of the well.

Abstract: A duct for connecting an electrical device insulated with gas with a terminal location located in atmospheric air, the duct has a gas filled bushing insulator, at least one tubular field control electrode located inside the bushing insulator, at least one insulating tube having an end facing a potential-guiding region of the duct, the at least one field control electrode being formed by a conducting portion on the end of the at least one insulating tube, a bushing conductor around which the at least one insulating tube is arranged coaxially, the insulating tube having a ground potential-side end, and a holder which holds the insulating tube at the ground potential-side end outside a region loaded with high field intensity.

Abstract: The present invention provides a floating shield for a high voltage bushing. Preferably the bushing is conically shaped and has a composite housing for substantially optimizing the electrical performance of the bushing according to the invention. The floating shield is preferably suspended within the bushing housing by a supporting insulator placed in a low electrical stress region of the bushing. In a preferred embodiment, the supporting insulator is disposed between a ground grading shield and the bushing housing. The composite housing preferably provides a protective inner tube made of a fiber reinforced material and an outer silicone rubber housing having weather sheds formed in a helix on the surface of the housing.

Abstract: A feedthrough bushing for a high voltage diode provides for using compression sealing for all sealing surfaces. A diode assembly includes a central conductor extending through the bushing and a grading ring assembly circumferentially surrounding and coaxial with the central conductor. A flexible conductive plate extends between and compressively seals against the central conductor and the grading ring assembly, wherein the flexibility of the plate allows inner and outer portions of the plate to axially translate for compression sealing against the central conductor and the grading ring assembly, respectively. The inner portion of the plate is bolted to the central conductor for affecting sealing. A compression beam is also bolted to the central conductor and engages the outer portion of the plate to urge the outer portion toward the grading ring assembly to obtain compression sealing therebetween.

Abstract: An entrance fitting assembly is disposed at an interface between a high voltage power cable and a high pressure oil filled cable termination to physically and electrically terminate the power cable skid wires, to seal the power cable pipe system to the cable termination and to filter the dielectric liquid flowing between the power cable pipe system and the cable termination. The entrance fitting assembly includes a centering and support plate for receiving and securing the cable skid wires, an elastomeric semi-stop or oil seal and an oil filter. In accordance with a preferred embodiment of the present invention, the oil filter is formed by a monolithic, polymeric, porous, open cell solid in a configuration of a thin annular disc.