A new ultra-fast HVDC Circuit breaker for meshed DC networks

• Published in: 11th IET International Conference on AC and DC Power Transmission p. 047
• Main Authors: Davidson, C.C, Whitehouse, R.S, Barker, C.D, Dupraz, J.-P, Grieshaber, W
• Format: Conference Proceeding
• Language: English
• Published: Stevenage, UK IET 2015; The Institution of Engineering & Technology
• Subjects: d.c. transmission; Power system protection; Switchgear; EU; steady-state power loss; Alstom grid; fast-rising fault current interruption; fault currents; meshed DC network; circuit breakers; power grids; ultra-fast HVDC circuit breaker; multiterminal DC grid; HVDC power transmission
• ISBN: 1849199825; 9781849199827
• DOI: 10.1049/cp.2015.0021

One of the major challenges of realising a Multi-Terminal DC grid has been the lack of a suitable HVDC Breaker. Previous designs of HVDC breaker were either too slow to be suitable for interrupting fast-rising fault currents or had conduction losses too high for economically viable operation on a grid. However, the new class of "hybrid" DC circuit breakers has fundamentally changed this position, with the potential of interrupting fault currents in a few milliseconds with negligible steady-state power losses. As part of the EU-funded "Twenties" project, Alstom Grid has built and tested a 120kV prototype DC breaker. The design of the breaker and the results obtained during testing are described in the paper.