Topology and control of a novel hybrid HVDC circuit breaker with self-powered capability

Abstract

Power supply for IGBT drive circuit of HVDC circuit breaker is a great challenge in practical engineering. At present, most of the HVDC circuit breakers rely on external power sources. This paper proposes a self-powered hybrid HVDC circuit breaker. The HVDC circuit breaker consists of an ultra-fast mechanical disconnector (UFD), a load commutation switch (LCS) and a main circuit breaker (MB). The LCS and the MB are formed by series connection of enhanced half-bridge sub-modules (EHBSMs). By this design, the energy stored in the EHBSM capacitor can be used for IGBT triggering. Thus, the self-powered function of the HVDC circuit breaker is realized. Three operation modes of the HVDC circuit breaker, including the star-up mode, the steady-state operation mode and the DC fault handling mode are analysed in detail. Finally, a four-terminal HVDC model is constructed in PSCAD simulation software. The simulation results verify the feasibility and effectiveness of the self-powered HVDC circuit breaker.

Keywords

• HVDC circuit breaker
• Self-powered
• Start-up
• DC fault
• Enhanced half-bridge sub-module