OPGW CABLE

Outer structure
OPGW is mainly composed of twisted metal wires such as aluminum-clad steel wires or aluminum alloy wires, which makes it similar in appearance and mechanical properties to traditional overhead ground wires. It can withstand a certain tension like ordinary overhead ground lines, and is used for lightning protection and other functions.
For example, in some high-voltage transmission lines, the outer metal wire of OPGW can effectively introduce the current generated by lightning strikes into the ground, protecting the transmission line from lightning damage.
Internal structure
The interior contains fiber optic units that are protected in a central or suitable location. The optical fiber unit usually consists of a loose sleeve fiber or a tightly packed fiber. The fiber is placed in a plastic sleeve filled with oil. This structure can buffer the external pressure and prevent the fiber from being damaged. The compact fiber is directly wrapped with a layer of thick protective material, and the structure is relatively compact.
Taking the loose sleeve optical fiber as an example, the oil paste can play the role of waterproof and moisture-proof, and can provide buffer when the optical fiber is stretched or bent to ensure the normal communication function of the optical fiber.

 

 

1.Lightning protection and communication function of power transmission line

In the transmission line, OPGW is used as the overhead ground wire. When the lightning strikes the transmission line, it can guide the lightning current into the earth and play the role of lightning protection. At the same time, the optical fiber inside can be used for communication. Through the optical signal transmission in the optical fiber, it can realize the voice communication, data transmission, monitoring signal transmission and other functions of the power system.
For example, in a large power grid system, optical fibers in OPGW can transmit control signals between substations, achieve remote control and monitoring of power equipment, and at the same time protect the safety of transmission lines during thunderstorms.

 

2.Principle of optical signal transmission

Optical fiber is based on the principle of total reflection of light for signal transmission. Light propagates in the optical fiber core, and the refractive index of the fiber core is higher than that of the cladding. When the light is incident at a certain Angle to the interface of the core and cladding, total reflection will occur, so that the optical signal can constantly reflect forward in the fiber, so as to achieve long-distance signal transmission.
For example, in the OPGW fiber, the optical signal emitted by the light source (such as a laser) enters the fiber after being modulated, and is transmitted in the fiber to the receiving end, which converts the optical signal into an electrical signal through a photodetector, and thus realizes the communication function.

 

 

 

 

 

 

 

1.Power system communication

It is widely used in high-voltage transmission lines to transmit dispatching telephone, remote signal, relay protection signal and so on. It can connect different substations, substations and dispatching centers to realize efficient communication and ensure the stable operation of power system.
For example, in large cross-regional power grids, OPGW can achieve hundreds or even thousands of kilometers of communication links to provide real-time data support for power dispatching.

 

2.Power system monitoring
Used to transmit monitoring equipment data, such as transmission line temperature, tension, meteorological conditions (wind speed, wind direction, ice cover, etc.) monitoring data. By installing various sensors on the transmission line, the data collected by the sensors can be transmitted to the monitoring center through OPGW optical fiber to achieve real-time monitoring of the status of the transmission line.
For example, when the transmission line is covered with ice, the ice monitoring sensor installed on the transmission line can transmit the data to the monitoring center through the OPGW fiber, and the staff can take timely measures to prevent the line from being damaged due to excessive ice.