Voltage Source Converter HVDC Links – The State of the Art and Issues Going Forward

This paper provides an overview of the state-of-the-art in voltage source HVDC at the present time. HVDC is introduced from its initial historical development, the introduction of line-commutated HVDC to present voltagesource HVDC designs. Converter control and coordination is discussed as are multi-terminal control and the need for DC breakers to facilitate such multi-terminal systems. Developments in DC breakers are reviewed. The importance of reliability, particularly of the cable, is highlighted and the issues surrounding cable modelling are briefly discussed. A summary of VSC-HVDC installations, both underway and planned, is given.