Multiline HVDC Circuit Breaker

Journal Paper

E. Kontos, T. Schultz, L. Mackay, L. M. Ramirez-Elizondo, C. M. Franck and P. Bauer, “Multiline Breaker for HVdc Applications,” in IEEE Transactions on Power Delivery, vol. 33, no. 3, pp. 1469-1478, June 2018. doi: 10.1109/TPWRD.2017.2754649

Abstract: This paper presents a breaker arrangement concept, the multiline breaker (MLB), for the protection of multiterminal high voltage dc (MTdc) networks. Based on the design of a hybrid breaker, the MLB is an economically attractive solution for the protection of multiple dc lines in nodal connection using a single main breaker path. By using commutation units, the MLB directs the fault current through the main breaker in a unidirectional way, irrespective of the fault location. Hence, this study presents the design requirements for the MLB, regarding both hardware and control, and evaluates its operation within a grid. For this reason, a four-terminal half-bridge multilevel modular converters-based MTdc grid in radial configuration was used and pole-to-ground dc fault conditions were investigated. The dc fault response of the grid with one MLB at the central node is compared to the respective response of the grid when one hybrid breaker is employed at each dc line. The simulations show that the MLB is feasible and that the overall MTdc grid fault response for the two protection systems is very similar. As a result, the design advantages of the MLB make it a promising solution for the dc fault isolation in MTdc grids.

keywords: circuit breakers; fault currents; fault location; HVDC power convertors; HVDC power transmission; power grids; power transmission faults; power transmission protection; voltage-source convertors; four-terminal half-bridge multilevel modular converters; fault conditions; dc fault response; MLB; hybrid breaker; dc line; MTdc grid fault response; dc fault isolation; multiline breaker; breaker arrangement concept; multiterminal high voltage dc networks; multiple dc lines; single main breaker path; fault location; Circuit faults; Switches; Circuit breakers; HVDC transmission; Hardware; Fault currents; Topology; Fault currents; HVdc circuit breakers; HVdc converters; HVdc transmission; Multiterminal networks


Mackay, L., and E. Kontos. “DC switch yard and method to operate such a DC switch yard.” World Intellectual Property Organization Patent WO2017034408 A 1 (2017).

This patent was filed by Delft University of Technology and marketed by DC Opportunities Technology BV. For more information and licensing options contact laurens.mackay (at)