CN211974573U - Direct-current mixed-voltage multi-loop branch tower and alternating-current mixed-voltage multi-loop branch tower - Google Patents
Direct-current mixed-voltage multi-loop branch tower and alternating-current mixed-voltage multi-loop branch tower Download PDFInfo
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- CN211974573U CN211974573U CN202020004361.4U CN202020004361U CN211974573U CN 211974573 U CN211974573 U CN 211974573U CN 202020004361 U CN202020004361 U CN 202020004361U CN 211974573 U CN211974573 U CN 211974573U
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Abstract
The utility model relates to an iron tower field specifically discloses a direct current thoughtlessly presses multiloop branch tower, including first body of the tower, its characterized in that, first body of the tower has connected gradually DC ground wire cross arm, DC high-voltage circuit cross arm and the direct current low pressure return circuit cross arm that is parallel to each other from last to down, the both ends of direct current low pressure return circuit cross arm are provided with direct current ground wire support piece respectively, direct current ground wire support piece sets up the top of direct current low pressure return circuit cross arm. The utility model discloses a direct current ground wire support piece carries out the layering with transmission line's ground wire for the wire satisfies the trade standard rather than the ground wire that the cooperation was used protection angle that becomes, thereby improves the ground wire lightning protection ability of branch tower.
Description
Technical Field
The utility model relates to an iron tower field, concretely relates to direct current thoughtlessly presses multiloop branch tower and exchanges thoughtlessly presses multiloop branch tower.
Background
Because of the scarcity of power corridor resources, the condition of mixed-voltage common-tower erection of power transmission lines with different voltage grades in local areas gradually appears, the mixed-voltage multi-loop branch tower is at the loop connection position, the ground wire lightning protection of the power transmission lines directly influences the working safety and reliability of the branch tower, the ground wire lightning protection in the prior art adopts a single-layer cross-arm multi-ground wire mode, but for the transregional power transmission special/extra-high voltage power transmission line, the requirement of the branch tower erection mode in the prior art cannot meet the requirement because the ground wire protection angle (the ground wire protection angle is the included angle between the vertical plane passing through the ground wire and the plane of the ground wire and the protected lightning-struck wire) is higher, and particularly, according to the industry specification, the special/extra-high voltage ground wire protection angle requirement is:
the protection angle of the plus or minus 500kV direct current single-circuit line ground wire is not more than 10 degrees;
the earth wire protection angle of +/-660 kV direct current single-circuit lines is not more than 0 degree in a flat hill mode, and is not more than-10 degrees in a mountainous area;
the minus or plus 800kV direct current single-circuit line ground wire should adopt a negative protection angle, and the angle is not more than-10 degrees in a mountainous area;
the protection angle of the 220 kV-750 kV alternating current double-circuit and multi-circuit line ground wire is not more than 0 degree;
the protection angle of the 1000kV alternating current double-circuit and multi-circuit line ground wire is not more than-3 degrees in a flat hill, and is not more than-5 degrees in a mountainous area.
Specifically, fig. 1 shows a dc mixed-voltage dual-loop branching tower erected according to the existing ground line lightning protection manner, a top layer of the dc mixed-voltage dual-loop branching tower is a dc ground line cross arm 11, a middle layer of the branching tower is a dc high-voltage loop cross arm 12, a lower layer of the dc mixed-voltage dual-loop branching tower is a dc low-voltage loop cross arm 13, and fig. 2 shows a top view of the dc mixed-voltage dual-loop branching tower, it can be seen from the top view of fig. 2 that a protection angle formed by a dc high-voltage loop ground line 121 and an inner side of a dc high-voltage loop lead 122 is greater than 0 °, a protection angle formed by a dc low-voltage loop ground line 131 and an inner side of a dc low-voltage loop lead 132 is greater than 10 °, and therefore the lightning protection requirement at the branch of the dc/ultra-high voltage transmission line cannot be met by adopting a single-.
Specifically, fig. 3 shows an ac mixed-voltage multi-loop branching tower erected in the existing ground wire lightning protection manner, the uppermost layer of the ac mixed-voltage multi-loop branching tower is an ac ground wire cross arm 21, as can be seen from the top view of fig. 4, the protection angle formed by the ac high-voltage loop ground wire 221 and the inside of the ac high-voltage loop lead 222 is greater than-3 °, the protection angle formed by the ac low-voltage loop ground wire 251 and the inside of the ac low-voltage lead 252 is greater than 0 °, and therefore the lightning protection requirement at the branch of the ac special/extra-high voltage transmission line cannot be met by adopting the single-layer cross arm multi-ground wire manner.
SUMMERY OF THE UTILITY MODEL
The utility model discloses a solve direct current special/superhigh pressure and mix when pressing tower frame altogether, ground wire lightning protection adopts single cross arm many ground wires mode easily to lead to the angle of protection can not satisfy the trade standard to lead to transmission line's the poor problem of ground wire lightning protection performance, provide a direct current and mix pressure multiloop branch tower, make this branch tower angle of protection satisfy the requirement.
The utility model provides a direct current thoughtlessly presses multiloop branch tower, includes first body of the tower, first body of the tower has connected gradually direct current ground wire cross arm, direct current high-voltage loop cross arm and the direct current low pressure return circuit cross arm that is parallel to each other from last to down, the both ends of direct current low pressure return circuit cross arm are provided with direct current ground wire support piece respectively, direct current ground wire support piece sets up the top of direct current low pressure return circuit cross arm.
Furthermore, the direct current ground wire cross arm and the direct current high-voltage circuit cross arm are matched to transmit +/-800 kV direct current, and the direct current ground wire supporting piece and the direct current low-voltage circuit cross arm are matched to transmit +/-500 kV direct current.
Furthermore, V-shaped jumper strings are respectively connected to the lower portions of the two ends of the direct-current high-voltage circuit cross arm, and I-shaped jumper strings are respectively connected to the lower portions of the two ends of the direct-current low-voltage circuit cross arm.
Further, the height of the dc ground support is set to 4.2 m.
The utility model discloses a solve exchange special/superhigh pressure and mix when pressing tower altogether and erect, ground wire lightning protection adopts single cross arm many ground wires mode easily to lead to the angle of protection can not satisfy the trade standard to lead to transmission line's the poor problem of ground wire lightning protection performance, provide an exchange and mix pressure multiloop branch tower, make this branch tower angle of protection satisfy the requirement.
The utility model provides an exchange and thoughtlessly press multiloop branch tower, includes the second body of the tower, the second body of the tower has connected gradually the interchange ground wire cross arm, interchange high-voltage circuit upper strata cross arm, interchange high-voltage circuit middle level cross arm, interchange high-voltage circuit lower floor cross arm, interchange low-voltage circuit upper strata cross arm and interchange low-voltage circuit lower floor cross arm that are parallel to each other from last to down, interchange low-voltage circuit upper strata cross arm's both ends are provided with interchange ground wire support piece respectively, interchange ground wire support piece sets up the top of low-voltage circuit upper strata cross arm.
Further, the alternating current ground wire cross arm, the alternating current high-voltage circuit upper layer cross arm, the alternating current high-voltage circuit middle layer cross arm and the alternating current high-voltage circuit lower layer cross arm are matched to transmit 1000kV alternating current, and the alternating current ground wire supporting piece, the alternating current low-voltage circuit upper layer cross arm and the alternating current low-voltage circuit lower layer cross arm are matched to transmit 500kV alternating current.
Furthermore, the lower parts of the two ends of the alternating current ground wire cross arm, the alternating current high-voltage circuit upper layer cross arm, the alternating current high-voltage circuit middle layer cross arm, the alternating current high-voltage circuit lower layer cross arm, the alternating current low-voltage circuit upper layer cross arm and the alternating current low-voltage circuit lower layer cross arm are respectively connected with an I-shaped jumper string.
Further, the height of the ac ground support is set to 4.5 m.
Compared with the prior art, the beneficial effects of the utility model are that:
1. the direct-current mixed-voltage multi-loop branch tower solves the problem that the protection angle cannot meet the requirement of the industry specification due to the fact that a single-layer cross arm multi-ground wire is arranged on a mixed-voltage common tower frame by arranging a direct-current ground wire supporting piece on a direct-current low-voltage loop cross arm, and improves the lightning protection capability of the direct-current mixed-voltage multi-loop branch tower ground wire;
2. the alternating current mixed-voltage multi-loop branch tower is provided with the alternating current ground wire supporting piece on the upper cross arm of the alternating current low-voltage loop, the problem that a single-layer cross arm multi-ground wire cannot meet the requirement of industry specifications due to the fact that the mixed-voltage common tower is provided with the single-layer cross arm multi-ground wire is solved, and the lightning protection capability of the alternating current mixed-voltage multi-loop branch tower ground wire is improved.
Drawings
FIG. 1 is a schematic diagram of the arrangement of the lead wires and the ground wires of a DC mixed-voltage multi-loop branch tower in the prior art;
FIG. 2 is a top view of the lead and ground wiring layout of a prior art DC mixed-voltage multi-loop branch tower;
FIG. 3 is a schematic diagram of the arrangement of the lead wires and the ground wires of the AC mixed-voltage multi-loop branch tower in the prior art;
FIG. 4 is a top view of the wire and ground layout of a prior art AC mixed-voltage multi-loop branching tower;
fig. 5 is a schematic structural diagram of an improved dc mixed-pressure multi-loop branch tower according to an embodiment of the present invention;
fig. 6 is a schematic diagram of the arrangement of the conducting wires and the ground wires of the improved dc mixed-voltage multi-loop branch tower according to an embodiment of the present invention;
fig. 7 is a top view of the arrangement of the conducting wires and the ground wires of the improved dc mixed-voltage multi-loop branch tower according to an embodiment of the present invention;
fig. 8 is a schematic structural diagram of an improved ac mixed-voltage multi-loop branch tower according to an embodiment of the present invention;
fig. 9 is a schematic diagram of arrangement of wires and ground wires of the improved ac mixed-voltage multi-loop branch tower according to an embodiment of the present invention;
fig. 10 is a top view of the arrangement of the conducting wires and the ground wires of the improved ac mixed-voltage multi-loop branch tower according to an embodiment of the present invention.
In the figure: 10 is a first tower body, 11 is a direct current ground wire cross arm, 12 is a direct current high-voltage loop cross arm, 13 is a direct current low-voltage loop cross arm, 14 is a direct current ground wire support piece, 121 is a direct current high-voltage loop ground wire, 122 is a direct current high-voltage loop lead, 131 is a direct current low-voltage loop ground wire, and 132 is a direct current low-voltage loop lead;
20 is a second tower body, 21 is an alternating current ground wire cross arm, 22 is an alternating current high-voltage loop upper layer cross arm, 23 is an alternating current high-voltage loop middle layer cross arm, 24 is an alternating current high-voltage loop lower layer cross arm, 25 is an alternating current low-voltage loop upper layer cross arm, 26 is an alternating current low-voltage loop lower layer cross arm, 27 is an alternating current ground wire support piece, 221 is an alternating current high-voltage loop ground wire, 222 is an alternating current high-voltage double-loop wire, 251 is an alternating current low-voltage loop ground wire, and 252 is an alternating current low-voltage double-loop wire.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
The first embodiment is as follows:
the embodiment provides a direct-current mixed-voltage multi-loop branch tower, as shown in fig. 5, which includes a first tower body 10, the first tower body 10 is sequentially connected with a direct-current ground wire cross arm 11, a direct-current high-voltage loop cross arm 12 and a direct-current low-voltage loop cross arm 13, which are parallel to each other, from top to bottom, the two ends of the direct-current low-voltage loop cross arm 13 are respectively provided with a direct-current ground wire support 14, the direct-current ground wire support 14 is arranged above the direct-current low-voltage loop cross arm 13, the direct-current ground wire support 14 is used for supporting a direct-current low-voltage loop ground wire 131, the ground wires of two power transmission loops in the embodiment are arranged in a layered manner, the problem that a single ground wire cross arm protection angle shared by the two loop ground wires cannot meet the industrial specification is solved.
Further, in the present embodiment, the dc ground cross arm 11 and the dc high-voltage circuit cross arm 12 cooperate to transmit ± 800kV dc power, and the dc ground support 14 and the dc low-voltage circuit cross arm 13 cooperate to transmit ± 500kV dc power.
Further, two ends of the direct current low-voltage loop cross arm 13 are connected with the I-type jumper string.
Further, the height of the dc ground support 14 is set to 4.2 m.
Specifically, as shown in fig. 6 and 7, after the ground wires of the mixed-voltage dual-loop power transmission line are layered by the dc ground wire supporting member 14, an included angle (protection angle) formed by the lead of each single loop and the ground wire thereof can meet the above-mentioned industry specifications, thereby improving the capability of ground wire lightning protection.
Further, simulation calculation is carried out on the lightning protection performance of the iron tower with the layered arrangement of the ground wires based on an electromagnetic transient program (EMTP) and an Electrical Geometric Model (EGM), and the simulation calculation result is as follows:
furthermore, electromagnetic environment simulation calculation is carried out on the iron tower with the layered arrangement of the ground wires, and the maximum field intensity of the surfaces of the direct-current high-voltage loop ground wire 121 and the direct-current low-voltage loop ground wire 131 is not larger than 18kV/cm, so that the requirements of industry specifications are met.
In conclusion, the ground wire layering of the mixed-voltage multi-loop power transmission line can meet the requirements of the industry specification and the engineering lightning flashover rate through the direct-current ground wire supporting piece 14.
Example two:
the embodiment provides an alternating current mixed voltage multi-loop branch tower, as shown in fig. 8, which includes a second tower body 20, the second tower body 20 is sequentially connected with an alternating current ground wire cross arm 21, an alternating current high voltage loop upper layer cross arm 22, an alternating current high voltage loop middle layer cross arm 23, an alternating current high voltage loop lower layer cross arm 24, an alternating current low voltage loop upper layer cross arm 25 and an alternating current low voltage loop lower layer cross arm 26, which are parallel to each other, from top to bottom, two ends of the alternating current low voltage loop upper layer cross arm 25 are respectively provided with an alternating current ground wire support 27, and the alternating current ground wire support 27 is arranged above the low voltage loop upper layer cross arm, so as to solve the problem that the ground wires of the alternating current high voltage loop and the alternating current low voltage loop share a single ground wire cross arm protection angle, which cannot meet the lightning protection standard, improve the.
Further, the alternating current ground wire cross arm 21, the alternating current high-voltage circuit upper layer cross arm 22, the alternating current high-voltage circuit middle layer cross arm 23 and the alternating current high-voltage circuit lower layer cross arm 24 are matched to transmit 1000kV alternating current, and the alternating current ground wire support member 27, the alternating current low-voltage circuit upper layer cross arm 25 and the alternating current low-voltage circuit lower layer cross arm 26 are matched to transmit 500kV alternating current.
Furthermore, the lower parts of two ends of the alternating current ground wire cross arm 21, the alternating current high-voltage circuit upper layer cross arm 22, the alternating current high-voltage circuit middle layer cross arm 23, the alternating current high-voltage circuit lower layer cross arm 24, the alternating current low-voltage circuit upper layer cross arm 25 and the alternating current low-voltage circuit lower layer cross arm 26 are respectively connected with an I-shaped jumper string.
Further, the height of the ac ground support 27 is set to 4.5 m.
Specifically, as shown in fig. 9 and 10, after the ground wires of the mixed-voltage four-loop power transmission line are layered by the ac ground wire supporting member 27, an included angle (protection angle) formed by the wire of each double loop and the ground wire thereof can meet the above-mentioned industry specification, thereby improving the capability of ground wire lightning protection.
Specifically, simulation calculation is performed on the lightning protection performance of the iron tower with the layered arrangement of the ground wires based on an electromagnetic transient program (EMTP) and an Electrical Geometric Model (EGM), and the simulation calculation result is as follows:
furthermore, electromagnetic environment simulation calculation is carried out on the iron tower with the layered arrangement of the ground wires, the maximum field intensity of the surfaces of the alternating-current high-voltage loop ground wire 221 and the alternating-current low-voltage loop ground wire 251 is not larger than 18kV/cm, and the requirements of industry specifications are met.
In conclusion, the alternating current ground wire support 27 enables the ground wire layering of the mixed-voltage multi-loop power transmission line to meet the requirements of industry specifications and engineering lightning flashover rate.
In summary, the dc mixed-voltage multi-loop branching tower and the ac mixed-voltage multi-loop branching tower provided by the invention adopt the ground wire layered structure, so that the included angle (protection angle) formed by the branch tower lead and the ground wire thereof can meet the requirement of the industry standard protection angle, thereby providing the ground wire lightning protection capability.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (8)
1. The utility model provides a direct current mixes many return circuits branch tower of pressure, includes first body of the tower (10), its characterized in that, first body of the tower (10) from last to connecting gradually mutually parallel direct current ground wire cross arm (11), direct current high pressure return circuit cross arm (12) and direct current low pressure return circuit cross arm (13) down, the both ends of direct current low pressure return circuit cross arm (13) are provided with direct current ground wire support piece (14) respectively, direct current ground wire support piece (14) set up the top of direct current low pressure return circuit cross arm (13).
2. The DC mixed-voltage multi-loop branching tower according to claim 1, wherein the DC ground cross arm (11) cooperates with the DC high-voltage loop cross arm (12) to transmit +/-800 kV DC power, and the DC ground support (14) cooperates with the DC low-voltage loop cross arm (13) to transmit +/-500 kV DC power.
3. The direct-current mixed-voltage multi-loop branch tower according to claim 2, wherein V-shaped jumper strings are connected below two ends of the direct-current high-voltage loop cross arm (12), and I-shaped jumper strings are connected below two ends of the direct-current low-voltage loop cross arm (13).
4. The DC mixed-voltage multi-loop branch tower according to claim 1, wherein the height of the DC ground support (14) is set to 4.2 m.
5. The utility model provides an exchange and mix pressure multiloop branch tower, includes second body of the tower (20), its characterized in that, second body of the tower (20) from last to having connected gradually mutually parallel interchange ground wire cross arm (21), interchange high voltage circuit upper strata cross arm (22), interchange high voltage circuit middle level cross arm (23), interchange high voltage circuit lower floor cross arm (24), interchange low pressure circuit upper strata cross arm (25) and interchange low pressure circuit lower floor cross arm (26) down, interchange low pressure circuit upper strata cross arm (25) both ends are provided with interchange ground wire support piece (27) respectively, it sets up to exchange ground wire support piece (27) the top of low pressure circuit upper strata cross arm.
6. The AC mixed-voltage multi-loop branch tower according to claim 5, wherein the AC ground wire cross arm (21), the AC high-voltage loop upper cross arm (22), the AC high-voltage loop middle cross arm (23) and the AC high-voltage loop lower cross arm (24) are matched to transmit 1000kV AC power, and the AC ground wire support (27), the AC low-voltage loop upper cross arm (25) and the AC low-voltage loop lower cross arm (26) are matched to transmit 500kV AC power.
7. The AC mixed-voltage multi-loop branch tower according to claim 5, wherein I-type jumper strings are respectively connected below two ends of the AC ground wire cross arm (21), the AC high-voltage loop upper-layer cross arm (22), the AC high-voltage loop middle-layer cross arm (23), the AC high-voltage loop lower-layer cross arm (24), the AC low-voltage loop upper-layer cross arm (25) and the AC low-voltage loop lower-layer cross arm (26).
8. AC mixed-voltage multi-loop branch tower according to claim 5, characterised in that the height of the AC ground support (27) is set to 4.5 m.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202020004361.4U CN211974573U (en) | 2020-01-02 | 2020-01-02 | Direct-current mixed-voltage multi-loop branch tower and alternating-current mixed-voltage multi-loop branch tower |
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| CN202020004361.4U CN211974573U (en) | 2020-01-02 | 2020-01-02 | Direct-current mixed-voltage multi-loop branch tower and alternating-current mixed-voltage multi-loop branch tower |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114909014A (en) * | 2022-05-27 | 2022-08-16 | 中国电力工程顾问集团西南电力设计院有限公司 | Branch strain tower of alternating current-direct current hybrid power transmission line |
| TWI839879B (en) * | 2022-10-04 | 2024-04-21 | 台灣電力股份有限公司 | Electronic device and method for determining length of wire cross-arm of wire supporting structure |
-
2020
- 2020-01-02 CN CN202020004361.4U patent/CN211974573U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114909014A (en) * | 2022-05-27 | 2022-08-16 | 中国电力工程顾问集团西南电力设计院有限公司 | Branch strain tower of alternating current-direct current hybrid power transmission line |
| CN114909014B (en) * | 2022-05-27 | 2024-04-05 | 中国电力工程顾问集团西南电力设计院有限公司 | Branch strain tower of alternating current-direct current hybrid transmission line |
| TWI839879B (en) * | 2022-10-04 | 2024-04-21 | 台灣電力股份有限公司 | Electronic device and method for determining length of wire cross-arm of wire supporting structure |
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