A transposition tower of a same-tower four-return power transmission line and a transposition method thereof

Abstract

This invention discloses a transposition tower for a four-circuit transmission line on the same tower and its transposition method. The tower has a first conductor suspension point on the first layer of conductor crossarms, a second and third conductor suspension points on the second layer, a fourth and fifth conductor suspension points on the third layer, and a sixth conductor suspension point on the fourth layer. The three-phase conductors suspended from the first, second, and third conductor suspension points on one side form one circuit, and the three-phase conductors suspended from the fourth, fifth, and sixth conductor suspension points on one side also form another circuit. This invention provides a simple tower structure for a four-circuit transmission line on the same tower. The transposition is achieved through a rolling change in the spatial position of two conductor spans, and the relative spatial positions of the conductors are clear and straightforward, solving the problem of difficult transposition in existing four-circuit transmission line installations on the same tower.

Description

Technical Field

[0001] This invention relates to a transposition tower for a four-circuit transmission line on the same tower and the transposition method thereof, belonging to the field of transmission engineering design technology. Background Technology

[0002] With socio-economic development and increasingly scarce land resources, the use of four-circuit transmission lines on the same tower can save valuable land resources. This method is one of the effective ways to improve the utilization rate of transmission corridors. However, four-circuit transmission lines on the same tower require conductor transposition measures. Without these measures, excessively high negative-sequence and zero-sequence voltages and currents in the system will lead to a decline in power quality at the load end, overheating and vibration of generators, and malfunctions of relay protection. In existing technologies, the compact conductor arrangement in four-circuit transmission lines on the same tower necessitates complex jumper connections for transposition, presenting difficulties in implementing single-circuit and double-circuit jumper transposition methods. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a transposition tower and transposition method for four-circuit transmission lines on the same tower. The tower structure is simple and the transposition of conductors is achieved by rolling the spatial position of two conductors. The spatial relative position relationship of the conductors is simple and clear, which can solve the problem of difficult transposition of existing four-circuit transmission lines on the same tower.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0005] A transposition tower for a four-circuit transmission line on the same tower includes a tower body. From top to bottom, the tower body is provided with a first layer of conductor crossarms, a second layer of conductor crossarms, a third layer of conductor crossarms, and a fourth layer of conductor crossarms. The first layer of conductor crossarms has a first conductor suspension point on each of its left and right sides. The second layer of conductor crossarms has a second conductor suspension point and a third conductor suspension point on each of its left and right sides. The third layer of conductor crossarms has a fourth conductor suspension point and a fifth conductor suspension point on each of its left and right sides. The fourth layer of conductor crossarms has a sixth conductor suspension point on each of its left and right sides. Three-phase conductors suspended from the first, second, and third conductor suspension points on one side constitute one circuit. Three-phase conductors suspended from the fourth, fifth, and sixth conductor suspension points on one side also constitute one circuit.

[0006] The crossarms on the left and right sides of the first layer, second layer, third layer, and fourth layer of conductor crossarms are arranged symmetrically.

[0007] The lengths of the first and fourth conductor crossarms are less than the lengths of the second and third conductor crossarms.

[0008] The three-phase conductors at the first conductor suspension point, the second conductor suspension point, and the third conductor suspension point are arranged in an upright triangle.

[0009] The three-phase conductors at the fourth, fifth, and sixth conductor suspension points are arranged in an inverted triangle.

[0010] A transposition method for a four-circuit overhead transmission line on the same tower, wherein the transposition method is used for a four-circuit overhead transmission line on the same tower in which the conductors are arranged with three layers of crossarms.

[0011] The conductor passes through the previous base tower, the first conductor suspension point, the second conductor suspension point and the third conductor suspension point on the transposition tower, and the next base tower, forming a two-stage connection of "inverted triangle - regular triangle - inverted triangle" in sequence, realizing the clockwise or counterclockwise shift adjustment of the phase sequence of one circuit line;

[0012] The conductor passes through the previous base tower, the fourth conductor suspension point, the fifth conductor suspension point, and the sixth conductor suspension point on the transposition tower, and then the next base tower, forming a two-stage connection of "upright triangle - inverted triangle - upright triangle" in sequence, realizing the clockwise or counterclockwise shift adjustment of the phase sequence of one circuit line.

[0013] The beneficial effects of this invention are as follows: This invention provides a transposition tower and transposition method for a four-circuit transmission line on the same tower. It adds a transposition tower with four layers of crossarms for the conductors, so that the upper two circuits are arranged in an "upright triangle" configuration, and the lower two circuits are arranged in an "inverted triangle" configuration. By utilizing two-span connections of "upright triangle-inverted triangle-upright triangle" or "inverted triangle-upright triangle-inverted triangle," a single clockwise or counterclockwise phase sequence adjustment is achieved for a four-circuit overhead transmission line on the same tower with three layers of crossarms. This transposition tower and method avoids the need for complex jumper connections on the same tower for transposition. The transposition is achieved through the rolling transformation of the spatial positions of the two conductor spans. The relative spatial positions of the conductors are simple and clear, the tower structure is simple, and it has strong practicality. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of a transposition tower for a four-circuit transmission line on the same tower according to the present invention;

[0015] Figure 2 This is a schematic diagram illustrating how the present invention achieves wire transposition using a "twisted triangle - regular triangle - inverted triangle" configuration.

[0016] Figure 3 This is a schematic diagram of the method of transposing wires using the "upright triangle - inverted triangle - upright triangle" of the present invention.

[0017] The diagram is labeled as follows: 1-First layer conductor crossarm; 2-Second layer conductor crossarm; 3-Third layer conductor crossarm; 4-Fourth layer conductor crossarm; 5-First conductor hanging point; 6-Second conductor hanging point; 7-Third conductor hanging point; 8-Fourth conductor hanging point; 9-Fifth conductor hanging point; 10-Sixth conductor hanging point. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to illustrate the technical solution of the present invention more clearly, and should not be used to limit the scope of protection of the present invention.

[0019] like Figure 1 As shown, the present invention discloses a transposition tower for a four-circuit transmission line on the same tower. The transposition tower includes four layers of conductor crossarms and a tower body. The tower body is provided with a first layer of conductor crossarm 1, a second layer of conductor crossarm 2, a third layer of conductor crossarm 3 and a fourth layer of conductor crossarm 4 arranged from top to bottom. Each layer of conductor crossarm is divided into a left crossarm and a right crossarm, and the left crossarm and the right crossarm are arranged symmetrically.

[0020] The lengths of the first-layer conductor crossarm 1 and the fourth-layer conductor crossarm 4 are shorter than the lengths of the second-layer conductor crossarm 2 and the third-layer conductor crossarm 3. The first-layer conductor crossarm 1 is a short crossarm, with a first conductor suspension point 5 on each side, which can suspend one phase conductor; the second-layer conductor crossarm 2 is a long crossarm, with a second conductor suspension point 6 and a third conductor suspension point 7 on each side, which can suspend two phase conductors; the third-layer conductor crossarm 3 is a long crossarm, with a fourth conductor suspension point 8 and a fifth conductor suspension point 9 on each side, which can suspend two phase conductors; the fourth-layer conductor crossarm 4 is a short crossarm, with a sixth conductor suspension point 10 on each side, which can suspend one phase conductor.

[0021] In this invention, the three-phase conductors suspended on one side of the first-layer conductor crossarm 1 and the second-layer conductor crossarm 2 of the transposition tower form a circuit, with the three-phase conductors arranged in an "upright triangle". Similarly, the three-phase conductors suspended on one side of the third-layer and fourth-layer crossarms of the transposition tower form a circuit, with the three-phase conductors arranged in an "inverted triangle". This transposition tower and transposition method are applicable to four-circuit overhead transmission lines on the same tower where the conductors are arranged with three layers of crossarms.

[0022] Specifically, such as Figure 2 As shown, the conductor passes through the previous base tower, the first conductor suspension point 5, the second conductor suspension point 6 and the third conductor suspension point 7 on the transposition tower, and the next base tower. This transposition tower and transposition method utilizes the two-stage connection of the conductor in the form of "inverted triangle - upright triangle - inverted triangle" to realize the clockwise or counterclockwise shift adjustment of the phase sequence of a circuit consisting of three-phase conductors suspended on one side of the first layer conductor crossarm 1 and the second layer conductor crossarm 2.

[0023] Specifically, such as Figure 3As shown, the conductor passes through the previous base tower, the fourth conductor suspension point 8, the fifth conductor suspension point 9 and the sixth conductor suspension point 10 on the transposition tower, and the next base tower. This transposition tower and transposition method utilizes the two-stage connection of the conductor "upright triangle - inverted triangle - upright triangle" to realize the clockwise or counterclockwise shift adjustment of the phase sequence of a circuit consisting of three-phase conductors suspended on one side of the third layer conductor crossarm 3 and the fourth layer conductor crossarm 4.

[0024] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A transposition method for a transposition tower of a four-circuit transmission line on the same tower, characterized in that: The transposition tower for the four-circuit transmission line on the same tower includes a tower body. From top to bottom, the tower body is provided with a first layer of conductor crossarms (1), a second layer of conductor crossarms (2), a third layer of conductor crossarms (3), and a fourth layer of conductor crossarms (4). The first layer of conductor crossarms (1) has first conductor suspension points (5) on its left and right sides, and the second layer of conductor crossarms (2) has second conductor suspension points (6) and third conductor suspension points (7) on its left and right sides, respectively. The third layer of conductor crossarms (3) has... The fourth conductor hanging point (8) and the fifth conductor hanging point (9) are provided. The left and right sides of the fourth layer conductor crossarm (4) are respectively provided with the sixth conductor hanging point (10). The three-phase conductors suspended by the first conductor hanging point (5), the second conductor hanging point (6) and the third conductor hanging point (7) on one side form a return line in an upright triangle arrangement. The three-phase conductors suspended by the fourth conductor hanging point (8), the fifth conductor hanging point (9) and the sixth conductor hanging point (10) on one side form a return line in an inverted triangle arrangement. The transposition method is used for four-circuit overhead transmission lines on the same tower with conductors arranged in a three-layer crossarm configuration. The conductor passes through the previous base tower, the first conductor hanging point (5), the second conductor hanging point (6) and the third conductor hanging point (7) on the transposition tower, and the next base tower, forming a two-stage connection of "inverted triangle - regular triangle - inverted triangle" in sequence, realizing the clockwise or counterclockwise shift adjustment of the phase sequence of one circuit. The conductor passes through the previous base tower, the fourth conductor hanging point (8), the fifth conductor hanging point (9) and the sixth conductor hanging point (10) on the transposition tower, and the next base tower, forming a two-stage connection of "regular triangle - inverted triangle - regular triangle" in sequence, realizing the clockwise or counterclockwise shift adjustment of the phase sequence of one circuit.

2. The transposition method for a four-circuit transmission line transposition tower on the same tower according to claim 1, characterized in that: The crossarms on the left and right sides of the first layer conductor crossarm (1), the second layer conductor crossarm (2), the third layer conductor crossarm (3) and the fourth layer conductor crossarm (4) are arranged symmetrically.

3. The transposition method for a four-circuit transmission line transposition tower on the same tower according to claim 1, characterized in that: The lengths of the first layer conductor crossarm (1) and the fourth layer conductor crossarm (4) are less than the lengths of the second layer conductor crossarm (2) and the third layer conductor crossarm (3).

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