Double-spliced cable leading-down structure of overhead line

Abstract

The utility model provides an overhead line double-spliced cable leading-down structure, which comprises a supporting base station arranged on the ground and located on one side of a pole tower or an iron tower; the three-phase cable terminals are arranged on the supporting base station at intervals, and a double-spliced cable is led out from each cable terminal; the plurality of lightning arresters are arranged on the supporting base station; three phases of double-split conductors, one end of each phase of double-split conductor is connected with the supporting base station through a lower lead suspension string, the other end of each phase of double-split conductor is hung on the corresponding cross arm through an upper lead suspension string, each phase of double-split conductor is connected with the corresponding phase of power transmission line, and a spacer is arranged between each phase of double-split conductor; each phase cable terminal head, the lightning arrester and the lower lead suspension string are connected through a connecting lead and a wire clamp group. According to the utility model, the requirement of current-carrying capacity can be met; meanwhile, the adopted independent supporting base station can be combined with different tower types, is not limited by sites, and occupies a small area.

Description

Technical Field

[0001] The utility model belongs to the technical field of high-voltage overhead lines, and particularly relates to a lead-down structure for a double-spliced cable of an overhead line. Background Art

[0002] With the development of urbanization, newly built 220 kV overhead lines generally adopt a cross-section of 2×630, and individual overhead line cross-sections adopt a cross-section of 4×300. However, the line path is restricted by external factors and cannot meet the requirement of using overhead lines throughout the line. The restricted path needs to adopt a cable line. Due to the skin effect of the current in the cable, when the cable cross-section reaches 2500, increasing the cable cross-section has little effect on the current. In system calculations, the maximum allowable current-carrying capacity of a 2500 cross-section copper conductor cable is only 1450 A, which cannot meet the maximum allowable current of 2×630 and 4×300 cross-section overhead lines.

[0003] In view of the above situation, in the current double-spliced cable project, some adopt the connection of a newly built terminal yard to the overhead line, which is often restricted by external conditions, and the newly built site cannot meet the construction requirements of the terminal yard. Content of the Utility Model

[0004] In view of this, the utility model aims to propose a lead-down structure for a double-spliced cable of an overhead line to solve at least one of the above problems.

[0005] To achieve the above object, the technical solution of the utility model is realized as follows:

[0006] The utility model provides a lead-down structure for a double-spliced cable of an overhead line. The top end of the lead-down structure is hung on a three-phase cross arm arranged on a pole tower or a steel tower. Each cross arm is connected to a transmission line through a strain insulator string, and includes:

[0007] A support base platform, which is arranged on the ground and on one side of the pole tower or the steel tower;

[0008] Three-phase cable terminal heads, which are arranged on the support base platform at intervals. Each cable terminal head leads out a double-spliced cable;

[0009] Lightning arresters, and a plurality of lightning arresters are all arranged on the support base platform;

[0010] Three-phase double-split conductors. One end of each double-split conductor is connected to the support base platform through a lower lead hanging string, and the other end is hung on the corresponding cross arm through an upper lead hanging string. Each double-split conductor is connected to the corresponding transmission line, and a spacer is arranged between each double-split conductor;

[0011] Each cable terminal head, lightning arrester and lower lead hanging string are connected through a connecting wire and a wire clamp group.

[0012] Further, the support base includes support columns and a support platform disposed on a plurality of support columns;

[0013] The three-phase cable terminal heads include an A-phase cable terminal head, a B-phase cable terminal head, and a C-phase cable terminal head on the same plane. Two cable terminal heads are provided for each phase. The two cable terminal heads are connected by a wire. The lightning arrester and the downlead suspension string are located between the two cable terminal heads.

[0014] Further, the distances between the downlead suspension string, the lightning arrester, and the cable terminal heads are all 2 m.

[0015] Further, double-conductor copper-aluminum transition equipment clamps are provided on each of the two cable terminal heads of each phase. The two double-conductor copper-aluminum transition equipment clamps are connected by a first connecting wire. A double-conductor double-downlead T-shaped clamp is provided on the first connecting wire.

[0016] Further, the downlead suspension string is disposed on the support platform. The double-conductor double-downlead T-shaped clamp is connected to the downlead suspension string by a second connecting wire. A double-conductor single-downlead T-shaped clamp is provided on the second connecting wire;

[0017] A single-conductor copper-aluminum transition equipment clamp is provided at the top of the lightning arrester. The single-conductor copper-aluminum transition equipment clamp is connected to the double-conductor single-downlead T-shaped clamp by a third connecting wire.

[0018] Further, a jumper string is hung on a cross arm of one phase of the iron tower. One phase of the double-split conductor is connected to the jumper string.

[0019] Further, the distance between the double-pin cables of the same phase is 2 m.

[0020] Further, the double-pin cable is connected to the cable terminal head disposed on other platforms. A cable protection pipe is sleeved outside the double-pin cable. The cable protection pipe is disposed on the ground;

[0021] The cable protection pipe is an MPP material protection pipe.

[0022] Compared with the prior art, the overhead line double-pin cable downlead structure of the present utility model has the following beneficial effects:

[0023] The double-spliced cable lead-down structure of the utility model can meet the lead-down arrangement requirements when the cable current-carrying capacity of the hybrid line does not meet the requirements and double-spliced cables need to be used, and can meet the demand for current-carrying capacity. At the same time, the independent support base and cable accessories are arranged in this embodiment. The independent support base can be combined with different types of poles and towers, is not restricted by the site, occupies a small area, and can be flexibly adjusted according to the actual situation on site. Brief Description of the Drawings

[0024] The drawings constituting a part of the present utility model are used to provide a further understanding of the present utility model. The schematic embodiments and descriptions thereof of the present utility model are used to explain the present utility model and do not constitute an improper limitation to the present utility model. In the drawings:

[0025] Figure 1 Front view of the lead-down structure applied to the pole tower in the embodiment of the present utility model;

[0026] Figure 2 Side view of the lead-down structure applied to the pole tower in the embodiment of the present utility model;

[0027] Figure 3 Front view of the lead-down structure applied to the iron tower in the embodiment of the present utility model;

[0028] Figure 4 Side view of the lead-down structure applied to the iron tower in the embodiment of the present utility model;

[0029] Figure 5 First detailed structure schematic diagram in the embodiment of the present utility model;

[0030] Figure 6 Second detailed structure schematic diagram in the embodiment of the present utility model.

[0031] Explanation of the reference numerals in the drawings:

[0032] 1 - Cable terminal head; 2 - Lightning arrester; 3 - Upper lead suspension string; 4 - Lower lead suspension string; 5 - Spacer; 6 - Double-conductor double-lead-down T-shaped clamp; 7 - Double-conductor copper-aluminum transition equipment clamp; 8 - Single-conductor copper-aluminum transition equipment clamp; 9 - Double-conductor single-lead-down T-shaped clamp; 10 - Cable protection pipe; 11 - Jumper string; 12 - Support base; 13 - Double-split conductor; 14 - Double-spliced cable. Detailed Embodiment

[0033] It should be noted that, without conflict, the embodiments and features in the embodiments of the present utility model can be combined with each other.

[0034] The present utility model will be described in detail below with reference to the drawings and in combination with the embodiments.

[0035] Please refer to Figures 1 to 4 As shown, this embodiment provides a lead-down structure for a double-spliced cable 14 of an overhead line. The top of the lead-down structure is hung on a three-phase cross arm set on a pole or a tower, and each cross arm is connected to a transmission line through a strain insulator string, including:

[0036] A support base 12, which is set on the ground and is located on one side of the pole or the tower;

[0037] Three-phase cable terminals 1, which are arranged at intervals on the support base 12. Two cable terminals 1 of each phase are connected by a wire, and a double-spliced cable 14 is led out from each phase of the cable terminal 1;

[0038] Lightning arresters 2, and a plurality of lightning arresters 2 are all set on the support base 12;

[0039] Three-phase double-split conductors 13. One end of each phase of the double-split conductor 13 is connected to the support base 12 through a lower lead suspension string 4, and the other end is hung on the corresponding cross arm through an upper lead suspension string 3. Each phase of the double-split conductor 13 is connected to the transmission line of the corresponding phase, and a spacer damper 5 is arranged between each phase of the double-split conductors 13;

[0040] Each phase of the cable terminal 1, the lightning arrester 2 (in this embodiment, a zinc oxide lightning arrester 22 is adopted) and the lower lead suspension string 4 are connected through a connecting wire and a wire clamp group.

[0041] Specifically, in this embodiment, for a high-voltage line hybrid line, a single cable cannot meet the current-carrying capacity requirement. At the same time, the on-site construction site cannot meet the requirements of the terminal yard. The double-spliced cable 14 lead-down structure adopted in this embodiment can meet the above requirements; at the same time, this embodiment adopts an independent support base 12 and the layout method of cable accessories. This independent support base 12 can be combined with different pole types, is not restricted by the site, occupies a small area, and can be flexibly adjusted and arranged according to the actual situation on site.

[0042] In some embodiments, the support base 12 includes support columns and a support platform arranged on a plurality of support columns;

[0043] The three-phase cable terminals 1 include an A-phase cable terminal 1, a B-phase cable terminal 1, and a C-phase cable terminal 1 located on the same plane. Two cable terminals 1 are provided for each phase of the cable terminal 1, and the lightning arrester 2 and the lower lead suspension string 4 are located between the two cable terminals 1;

[0044] Two double-spliced cables 14 are provided for each phase. The distance between the two double-spliced cables 14 of the same phase is 2 m. The two double-spliced cables 14 are connected from the cable trench to the cable terminal 1 through a platform. A cable protection pipe 10 is also sleeved outside the double-spliced cable 14. The cable protection pipe 10 is set on the ground, and the cable protection pipe 10 adopts an MPP material protection pipe;

[0045] The distances between the lower lead suspension string 4, the lightning arrester 2 and the cable terminal head 1 are all 2 m.

[0046] Specifically, in this embodiment, a support base 12 is provided. The support base 12 is arranged on the ground, on one side of the pole tower or iron tower, and does not need to be connected to the pole tower. The electrical clearance is controllable. The cable terminal head 1, the lightning arrester 2 and the lower lead suspension string 4 are concentratedly arranged on the support base 12. The formed independent cable platform can be combined with different types of pole towers. The size of this platform is 17.6 m * 6.3 m * 7.2 m (the height of the platform maintenance fence is 1.2 m), the loop spacing is 3.5 m, the distance between the double - stranded cables 14 of the same phase is 2 m (the cable terminal heads 1 are located in the same plane, and the lightning arrester 2 and the lead suspension string are located in the middle of the two cable terminal heads 1), and the distances between the lead suspension string, the lightning arrester 2 and the cable terminal head 1 are all 2 m.

[0047] It should be noted that magnetic isolation treatment is carried out at the steel fracture between the cable terminal head 1 and the lightning arrester 2 to prevent eddy currents. The size design of the above layout can be adjusted according to the actual on - site situation under the condition of meeting the electrical clearance.

[0048] The double - stranded cable 14 is arranged at the bottom end of the support base 12, and a 18 - m - long cable protection pipe 10 is arranged on the ground to prevent the cable near the ground from being damaged, effectively protecting the outer surface of the cable and improving the overall safety.

[0049] In some embodiments, as Figure 5 and Figure 6 shown, on each of the two cable terminal heads 1 of each phase, double - conductor copper - aluminum transition equipment clamps 7 are provided. The two double - conductor copper - aluminum transition equipment clamps 7 are connected by a first connecting wire, and a double - conductor double - lead - down T - type clamp 6 is arranged on the first connecting wire.

[0050] The lower lead suspension string 4 is arranged on the support platform. The double - conductor double - lead - down T - type clamp 6 is connected to the lower lead suspension string 4 through a second connecting wire, and a double - conductor single - lead - down T - type clamp 9 is arranged on the second connecting wire;

[0051] At the top end of the lightning arrester 2, a single - conductor copper - aluminum transition equipment clamp 8 is provided. The single - conductor copper - aluminum transition equipment clamp 8 is connected to the double - conductor single - lead - down T - type clamp 9 through a third connecting wire.

[0052] A jumper string 11 is hung on one of the cross - arms of the iron tower, and one of the double - stranded cables 14 of one phase is connected to the jumper string 11.

[0053] Specifically, in this embodiment, when connecting the cable terminal head 1, the lightning arrester 2 and the lower lead suspension string 4, the cooperation mode of each clamp and the connecting wire is adopted, the overall layout is more concise and reasonable, the arrangement of each connecting wire is regular, and the on - site installation is more standardized.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered by the scope of the claims and the specification of the present invention.

[0055] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A double-cable downlead structure for overhead lines, wherein the top of the downlead structure is hung on a three-phase crossarm arranged on a pole or iron tower, and each crossarm is connected to a transmission line through a tension insulator string, characterized in that: include: A supporting base, which is arranged on the ground and located on one side of the pole tower or the iron tower; Three-phase cable terminal heads, the three-phase cable terminal heads are arranged on the support base at intervals, and each phase of the cable terminal head leads out a double-spliced ​​cable; Lightning arresters, a plurality of said lightning arresters are arranged on said supporting base; Three-phase double-split conductors, one end of each phase of the double-split conductor is connected to the support base through a lower lead wire hanging string, and the other end is hung on the corresponding cross arm through an upper lead wire hanging string, each phase of the double-split conductor is connected to the corresponding phase of the power transmission line, and a spacer bar is provided between the double-split conductors of each phase; The cable terminal head, the lightning arrester and the lower lead suspension string of each phase are connected through connecting wires and a wire clamp group.

2. The overhead line double-cable downlead structure according to claim 1, characterized in that: The support base includes support columns and a support platform arranged on the plurality of support columns; The three-phase cable terminal head includes an A-phase cable terminal head, a B-phase cable terminal head and a C-phase cable terminal head located on the same plane. Two cable terminal heads are provided for each phase. The two cable terminal heads are connected by wires. The lightning arrester and the lower lead string are located between the two cable terminal heads.

3. The overhead line double-cable downlead structure according to claim 2, characterized in that: The distances between the lower lead string, the lightning arrester and the cable terminal head are all 2m.

4. The overhead line double-cable downlead structure according to claim 2, characterized in that: A double-conductor copper-aluminum transition device wire clamp is respectively arranged on the two cable terminal heads of each phase, and the two double-conductor copper-aluminum transition device wire clamps are connected by a first connecting wire, and a double-conductor double-lead T-type wire clamp is arranged on the first connecting wire.

5. The overhead line double-cable downlead structure according to claim 4, characterized in that: The lower lead hanging string is arranged on the supporting platform, the double-conductor double-lead lower T-shaped wire clamp is connected to the lower lead hanging string through a second connecting wire, and the second connecting wire is provided with a double-conductor single-lead lower T-shaped wire clamp; A single-conductor copper-aluminum transition device clamp is provided at the top of the arrester, and the single-conductor copper-aluminum transition device clamp is connected to the double-conductor single-lead T-type clamp through a third connecting conductor.

6. The overhead line double-cable downlead structure according to claim 1, characterized in that: A jumper string is hung on one phase cross arm of the iron tower, and one phase of the double split conductor is connected to the jumper string.

7. The overhead line double-cable downlead structure according to claim 1, characterized in that: The spacing between the double cables in the same phase is 2m.

8. The overhead line double-cable downlead structure according to claim 1, characterized in that: The double-spliced ​​cable is connected to the cable terminal head arranged on other platforms, and the double-spliced ​​cable is also sheathed with a cable protection tube, and the cable protection tube is arranged on the ground; The cable protection tube is made of MPP material.

Images