CN2582240Y

CN2582240Y - Dry, prefabricated and capacitance type cable terminal

Info

Publication number: CN2582240Y
Application number: CN 02282771
Authority: CN
Inventors: 许建国
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-11-01
Filing date: 2002-11-01
Publication date: 2003-10-22
Anticipated expiration: 2012-11-01

Abstract

The utility model relates to a dry, prefabricated and capacitance type cable terminal, which is composed of an inverse conical capacitance bushing, a stress cone, end conductors, a root part shielding drum, etc. The utility model is characterized in that the interior of the main insulation of the inverse conical capacitance bushing is provided with capacitance plates which are in a coaxial staggered arrangement from inside to outside and from top to bottom; the inner surface of the root part of the inverse conical capacitance bushing is in the shape of a bell mouth and is matched with the shape of the outer surface of a conical isolated terminal of the stress cone in close contact without a gap. The utility model has the advantages of prefabrication by factories, on-site assembly, easy controlled quality, dry type insulation without oil filling, convenient operation and maintenance and good effect on voltage sharing; the utility model can be used for extra-high-tension cables.

Description

Dry type prefabricated capacitor type cable termination

Technical field the utility model relates to a kind of dry insulation prefabricated capacitor type cable termination, belongs to the electric cable accessories field.

Background technology is present, and 35kV and following plastic insulation power cable mostly adopt the prefabricated terminals, and these prefabricated cable terminals all adopt rubber and plastic class material, and it is no longer oil-filled, be usually said dry insulation, thus easy to install, in service without repair and maintenance.Yet the terminals of patterns such as the general wrapped banding pattern that uses of the above plastic insulation high-tension cable of 35kV, prefabricated plug-in type also do not have dry type prefabricated product at present.Wrapped banding pattern can be made dry insulation, but need make at building-site, can't be prefabricated in the factory and carry out quality inspection, and the site operation cycle is long, more difficult control of quality.Advanced is prefabricated plug-in type at present, its core component stress cone adopts ethylene-propylene rubber or silastic material, make in advance in factory, can carry out strict quality inspection in factory, at the scene of laying it is set on the cable insulation, its outer suit insulated porcelain sleeve is filled insulating oil again between insulated porcelain sleeve and stress cone-cable insulation.Prefabricated plug-type advantage is that its core component can be tested in factory, and it is little to lay the work on the spot amount, thereby is easy to control of quality; Its shortcoming is that the effect of stress cone reduction root field intensity is limited, thereby makes with dry insulation fully than difficulty, also needs to fill insulating oil, thereby relatively heavier, and the operation maintenance workload is also bigger.

Hydraulic oil paper insulation power cable is used the tapered terminal fitting box of electric capacity always.Such as, " power cable design principle " (Zhuo Jinyu writes a book, Beijing: China Machine Press, 1994.4) introduced the tapered terminal of a kind of prefabricated electric capacity, its primary structure is: the electric capacity awl that is used for all pressing surrounds bakelite tube, the bakelite tube that will have the electric capacity awl during construction is enclosed within the cable insulation outside, and ground floor pole plate on the bakelite tube (zero screen) is led core with cable and is connected, and outermost layer pole plate (end screen) connects cable shield.Suit insulated porcelain sleeve outside the electric capacity awl, the space segment in the insulator is filled with cable insulating oil.The advantage of electric capacity wimble structure is that the effect specific stress wimble structure of reduction root electric field strength is much better, therefore is used for high-tension cable.This structure is applicable to the paper oil insulation cable, but is unsuitable for plastic insulated cable, because there is certain slit between bakelite tube and the cable insulation, this slit needs the insulating oil of high electric strength to fill.For oil paper cable, the processing of insulating oil, check are necessary, and concerning plastic cable, then should avoid using, and adopt dry insulation as far as possible.

The purpose of this utility model is to overcome the shortcoming of above prior art, for the high-pressure plastic insulated power cable designs a kind of dry insulation, prefabricate, terminal fitting with capacitor voltage equalizing structure.

Summary of the invention to achieve these goals, the utility model adopts following project organization:

Dry type prefabricated capacitor type cable termination, by anti-taper capacitance graded bushing, stress cone, the end electric conductor, compositions such as root casing, it is characterized in that: have the electric conducting material of the arranged in co-axial alignment that staggers successively from the inside to the outside or the capacitance plate that semiconductive material is made in the main insulation of described anti-taper capacitance graded bushing from top to bottom, the inner surface of the root insulating cylinder of described anti-taper capacitance graded bushing is that the little lower end diameter of upper end diameter is toroidal greatly, the insulating end outer surface of described stress cone is that the little lower end diameter of upper end diameter is tapered greatly, the taper insulated outer surface shape of the toroidal inner surface of the root insulating cylinder of described anti-taper capacitance graded bushing and described stress cone is coincide and be there is no slots close and contact, the root insulating cylinder of the toroidal of described anti-taper capacitance graded bushing is made by the high electric strength insulating material, and described stress cone is made by elastomeric material.

Except above-mentioned essential features, can replenish following technology contents in concrete the enforcement:

Described stress cone is withstood by the stress cone carriage with spring, make it to contact tightr with the inner surface of the root insulating cylinder of described anti-taper capacitance graded bushing.

Interior one deck capacitance plate (zero screen) is led core with cable and is electrically connected, and outermost one deck capacitance plate (end screen) is electrically connected with the metal screen layer of cable.

The utlity model has following characteristics:

1. anti-taper capacitance graded bushing, stress cone etc. all are solid materials, and be not oil-filled in the cable termination, is the dry insulation structure, installs simply, moves non-maintaining.

2. anti-taper capacitance graded bushing, stress cone etc. are all made in factory and check, and assembly working is only carried out in the job site, and short construction period is easy to control of quality.

3. the mode that adopts the electric capacity awl to combine with stress cone, under situation reasonable in design, much lower when the maximum field strength ratio in the cable termination adopts stress cone merely.Therefore, the utility model cable termination can be used for the plastic insulation power cable of supergrid.

Description of drawings Fig. 1 is anti-taper capacitance graded bushing structural representation.

Fig. 2 is the stress cone structural representation.

Fig. 3 is the structural representation that cable termination and cable are assembled together.

Describe embodiment of the present utility model in detail below in conjunction with accompanying drawing.Embodiment the utility model dry type prefabricated capacitor type cable termination is made up of anti-taper capacitance graded bushing (Fig. 1), stress cone (Fig. 2), end electric conductor 10, root casing 17 etc.The first half of anti-taper capacitance graded bushing (Fig. 1) is identical with common capacitance graded bushing, all is to be born along face insulation task by outer surface; Its latter half is then opposite with ordinary casing, is to be born along face insulation task by inner surface, therefore is referred to as anti-taper capacitance graded bushing.The inner surface of the root insulating cylinder 5 of this sleeve pipe is the big toroidal of the little lower end diameter of upper end diameter (being referred to as anti-cone-shaped inner surface); The outer surface of the insulating end 8 of stress cone (Fig. 2) is similarly the big taper of the little lower end diameter of upper end diameter (being referred to as positive conical outer surface); And the positive taper external surface shape of the anti-cone-shaped inner surface of sleeve pipe and stress cone matches, and they can closely contact in seamless unoccupied place under certain pressure.For guaranteeing contact closely, stress cone is made by elastomeric material.The root insulating cylinder 5 of the toroidal of anti-taper capacitance graded bushing by the electric and all higher insulating material of mechanical strength make (such as, can use fiber glass epoxy).The upper end continued access pipe of toroidal insulating cylinder 5 (as shown in Figure 2, pipe and horn mouth tube can be made into one).Pipe and horn mouth tube are made sleeve pipe main insulation 3 outward, and the capacitance plate 4 of the arranged in co-axial alignment that from top to bottom staggers successively from the inside to the outside is set in sleeve pipe main insulation 3, and capacitance plate 4 is made by electric conducting material (such as aluminium foil) or semiconductive material (such as the semiconductive resin).Sleeve pipe main insulation 3 and capacitance plate 4 constitute the capacitance core of anti-taper.The outer environment for use according to cable termination of capacitance core is installed oversheath 2.Such as, for the cable termination that in atmospheric environment, uses, can install the oversheath 2 of band silicon rubber full skirt; To being used for the cable termination of transformer, oversheath 2 should be able to tolerate transformer oil; To being used for the cable termination of SF6 air insulating device, oversheath 2 should adopt the insulating material manufacturing that adapts.The end of anti-taper (top) is installed end envelope 1 and flange 6 respectively with root (bottom).

The insulating end 8 and the conducting end 9 of stress cone (Fig. 2) all use elastomeric material (such as silicon rubber, ethylene-propylene rubber etc.) to make.

When install the job site, cable is peelled off sheath, scraped off the screen outside the cable main insulation 21; Be set to root casing 17, spring 16, stress cone carriage 15 on the cable body downwards in advance; Stress cone is set to outside the main insulation 21, anti-taper is set on the stress cone; End electric conductor 10 and cable are led core 20 firm crimping; With screw 12 anti-taper is fixed on the end electric conductor 10, between end electric conductor 10 and the end envelope 1 sealing ring 13 is housed; Stress cone shifted onto with anti-taper closely contact, the afterbody of the conducting end 9 of stress cone is fixed on the cable insulation outer shielding layer 22; Stress cone carriage 15, spring 16, root casing 17 are upwards return, root casing 17 is connected with the flange 6 of anti-taper with screw 14; With encapsulant 18 (such as fluid sealant or lead sealing) root casing 17 is fixed on the cable jacket 23.At last end cap 11 is fixed on the end electric conductor 10.

Claims

1. dry type prefabricated capacitor type cable termination, by anti-taper capacitance graded bushing, stress cone, the end electric conductor, compositions such as root casing, it is characterized in that: have the electric conducting material of the arranged in co-axial alignment that staggers successively from the inside to the outside or the capacitance plate that semiconductive material is made in the main insulation of described anti-taper capacitance graded bushing from top to bottom, the inner surface of the root insulating cylinder of described anti-taper capacitance graded bushing is that the little lower end diameter of upper end diameter is toroidal greatly, the insulating end outer surface of described stress cone is that the little lower end diameter of upper end diameter is tapered greatly, the taper insulated outer surface shape of the toroidal inner surface of the root insulating cylinder of described anti-taper capacitance graded bushing and described stress cone is coincide and be there is no slots close and contact, the root insulating cylinder of the toroidal of described anti-taper capacitance graded bushing is made by the high electric strength insulating material, and described stress cone is made by elastomeric material.

2. dry type prefabricated capacitor type cable termination as claimed in claim 1, it is characterized in that: described stress cone is withstood by the stress cone carriage by spring, makes described stress cone insulating end outer surface and seamless tight contact of the inner surface of the root insulating cylinder of described anti-taper capacitance graded bushing.