HVDC transmission system performance from EMC perspective

HVDC technology deals with efficient transportation of hundreds of million watts of electrical power through conversion from ac to dc at the source end and dc to ac at the load end. Irrespective of system configuration, the converter generates a significant amount of power harmonics and feeds onto the transmission system. Systems of this kind couple unwanted electrical noise into co-located telephone circuits. This paper analyses the generation and coupling mechanism of power harmonics from HVDC to telecommunication systems and describes a case study involving underground telephone cables running parallel to HVDC transmission lines.