An optical repeater technology for ultra-long haul optical communication in ultra-high voltage grid system

Ultra-high Voltage (UHV) grid will become the backbone of China's future strong and smart grid. However, some new problems have arisen, such as ultra-long haul communication for UHV grid. At present, Optical Fiber Composite Overhead Ground Wire (OPGW) is widely deployed for power communication system, and repeater stations are required for long haul communication. As the UHV lines usually cross over some areas where setting up and maintaining repeater stations are difficult, this paper proposes a new idea to replace repeater stations by adopting cascade erbium doped fiber amplifiers with power supply from current transformer, solar cells and accumulator battery. By using this method, the repeater can be mounted on the power towers along the UHV line because of its small size, low weight and anti-electromagnetic interference characteristic, and the whole system provides a stable and reliable relay function for ultra-long haul optical communication.