DC vacuum circuit breaker

Abstract

In the last years the progressive increase of distributed and non-programmable energy sources arise the interest in the use of DC for medium-voltage distribution systems. The study focuses on the design considerations of the apparatus required to support the management and protection of these applications. The fault-handling techniques in DC distribution system is introduced and the definition of the main requirements for the circuit breakers is supported by computer simulations of short-circuit current interruptions. A medium-voltage DC circuit breaker designed for 12 kV and 2.5 kA nominal current and 15 kA interrupted short-circuit current is presented. The functionalities and the performances are illustrated by means the experimental results obtained from high power tests.