transposition tower
{{Update|date=March 2024}}
In electrical power transmission, a transposition tower is a transmission tower that changes the relative physical positions of the conductors of a transmission line in a Polyphase system. A transposition tower allows these sections to be connected together, while maintaining adequate clearance for the conductors. This is important since it distributes electrical impedances between phases of a circuit over time, reducing the problem of one conductor carrying more current than others.
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Double-circuit lines are usually set up with conductors of the same phase placed opposite each other. This reduces the reactance due to mutual inductance; the reactance of both circuits together is less than half that of one circuit. For example, a section of a line may be (top-to-bottom) phases A-B-C on the left, also phases C'-B'-A' on the right. The next section may be B-C-A on the left, also A'-C'-B' on the right. Therefore, the rotation on each side of the tower will be opposite.{{Cite web |last=Technology |first=Electrical |date=2024-04-15 |title=Why are Conductor Positions Swapped in a Transposition Tower? |url=https://www.electricaltechnology.org/2024/04/transposition-tower-position-overhead-conductor-exchanged.html/amp |access-date=2024-08-23 |website=ELECTRICAL TECHNOLOGY |language=en-US}}
Gallery
Verdrillmast_Oberwoehr.jpg|Here, on the right the phases are rotated; on the left, two phases are swapped, thus the rotation sense changed.
Facility4508_Pylon206.JPG|Transposition tower. On the right side, the phases are rotated upward, on the left side downward.
Verdrillung im Spannfeld noerdlich Malmoe2002.png|Transposition in the span field of a 420 kV-line in Sweden
380_kV_çaprazlama_-_panoramio.jpg|Transposition on a single-phase line
View of transposition towers on MWD 1 northeast of Mead Substation, view north-northeast - Hoover Dam, Metropolitan Water District Line 1, U.S. Highway 93, Boulder City, Clark County, HAER NV-27-P-8.tif|Transposition by using multiple towers
Tannenbaum_pylon3_poland.jpg|Transposition by using elongated traverses
See also
{{Commons category|Transposition towers}}
External links
{{Reflist}}
- [https://www.acotemporarypower.com/ Temporary Electric Pole]