Abstract:
The subject of the invention is a high-voltage bushing applicable in electric power engineering. The high-voltage bushing comprises a condenser core (1) and electrically conducting field-grading layers (3) which are arranged coaxially around the central conductor (2) and are embedded in insulating material (4) of the condenser core (1). An electric connection (6) is provided to at least one layer (3a) of the field-grading layers (3) by means of a current-collecting member (5). The layer (3a) is made in form of thin metal film deposited on an electrically insulating substrate layer or in form of a percolating network of conductive particles suspended in a layer of electrically insulating material, and the current-collecting member (5) is positioned on the surface of the layer (3a) and it covers a part of the surface area of the layer (3a) and has the surface resistivity many times smaller than the surface resistivity of the layer (3a). The current-collecting member (5) is shaped so that the length of the contour line of its circumference (L) is greater than the length of the shorter side of the layer (3a).
Abstract:
The subject of the invention is an insulating structure with screens shaping the electric field, applicable in high-voltage bushings, high-voltage cables, cable accessories and in measuring instruments, especially instrument transformers. The structure according to the invention comprising layers of electrically insulating material between which there are inserted conducting sheets which are screens shaping the electric field in high-voltage electric power equipment is characterized in that the conducting sheets are made of an insulating substrate layer with a porous structure, impregnatable and compressible along the direction parallel to the sheet plane, and at least one surface of the substrate layer has a strongly developed surface and is coated with a metal layer.
Abstract:
The invention relates to a component made of the materials of two thermoplastics, to its production method and to a constituent part of the insulating system of a low, medium or high voltage electric apparatus containing the component according to the invention. The component comprises a substrate (A) of the material of one thermoplastic and a surface layer (B) made of the material of the second thermoplastic, which are bonded to each other through a specific intermediate layer (C) formed from the material of the thermoplastic of the substrate (A) and from the material of the thermoplastic of the surface layer (B), forming a component of enhanced mechanical resistance for broad range of applications, especially in demanding operating conditions in high electric fields. The surface layer (B) is preferably applied on the outer layer (A1), specifically formed on the substrate (A), in the thermoplastic injection molding process.