Monitoring Technologies for HVDC Transmission Lines

HVDC transmission systems are becoming more prevalent because of the advantages they offer. They are more efficient and environmentally friendly and are becoming preferred in distributed power generation. The reliable operation of HVDC transmission lines requires distributed, online monitoring, which is not as well-developed as those in an HVAC system. The advancement of HVDC systems will require online monitoring that provides information on the operating and environmental conditions, mechanical stress on the conductors and the structure, vegetation clearance, and security of the system. This perspective paper provides a thorough overview of the state-of-the-art technologies that are applicable to the monitoring of HVDC transmission lines. The challenges and future direction in the development of sensors for HVDC applications are highlighted. One of the key challenges unique to HVDC transmission lines is energy harvesting from the transmission line conductors to provide power for the monitoring equipment. This paper reviews the potential technologies for energy harvesting from HVAC transmission lines and their suitability for employment in HVDC transmission lines.