Comprehensive design procedure and control of a hybrid circuit breaker with adaptable pulse current injection

Abstract

Hybrid circuit breakers are key components for high voltage DC transmission as they are the only way to avoid a complete shutdown of a DC grid in case of faults. In this paper, we focus on the design of a new hybrid circuit breaker with improved current injection, which allows fast and reliable arc extinction in the mechanical switch that conducts the line current under normal operation conditions. After presenting the turn-off procedure, the design of the switching modules and the optimization of the pulse circuit are shown. Additionally, a reliable control is presented, which adapts the pulse current to the line current and ensures successful current interruption.