A Hybrid DC Circuit Breaker with Capability of Reducing Reclosing Shock

Abstract

In this paper, a new hybrid DC circuit breaker (HDCCB) that can reduce the second shock of reclosing on a permanent fault is proposed. With overhead lines as DC links, DC systems are prone to temporary faults. Therefore, it is crucial for HDCCBs to reclose to ensure the power supply. But the potential second damage caused by a reclosing failure can be harmful to system security. This paper minimizes the reclosing shock by adding a reclosing damper behind the main breaker of HDCCB, and proposes a reclosing strategy to realize a reliable identification of permanent faults. What's more, the application of the proposed HDCCB in fault location is analysed. Finally, the effectiveness of the proposed HDCCB and reclosing strategy are validated through the simulation on PSCAD/EMTDC.