An Optical Ground Wire (OPGW) is a type of cable used in overhead power lines. An OPGW cable consists of one or more aluminum or stainless steel tubes containing a certain number of optical fibers. These tubes are surrounded by layers of steel wires coated with aluminum, and in subsequent layers, steel, aluminum, and aluminum alloy wires or a combination thereof, depending on the desired electrical and mechanical specifications. By combining aluminum wires with cold-worked steel wires and aluminum alloy wires, various electrical and mechanical properties can be achieved.
The number of optical fibers used in the tubes can vary and can start from 1 fiber and go up to numbers such as 48, 24, 12, or even higher based on customer needs and requests. OPGW cables are used at the highest point of transmission line towers. In the production and design of OPGW cables, both single-mode and multi-mode fibers can be used. Single-mode fibers are used for distances greater than one kilometer with high bandwidth, while multi-mode fibers are used for distances less than one kilometer with lower bandwidth.
Applications and uses
This cable is used in transmission lines to protect the phase conductors carrying electric current from short-circuit currents, lightning surge currents, ground these currents through transmission towers, and transmit audio and visual data using optical fibers.
