The Basic Principle and the Breaking Characteristics of the Composite Resistance Commutatiion Type DC Load Breaker

For the faults such as the grounding of DC transmission lines, the capability of DC breaker is only to be able to interrupt a load current because of the control functions of converter. So a simple interrupting system of DC load current is proposed here by making use of the composite resistance commutating system with three parallel circuits consisting of, a normally current passing electrode, a high voltage generating fusing element, and an energy dissipating non-linear resistance. This load breaker has suitable performance for high voltage interruption by using a multi-stage fusing element. For high current interruption a set of a gap in series to the fusing element is recommended.