Resistive SFCL Integrated Ultra-fast DC Hybrid Circuit Breaker for Subsea HVDC Transmission Systems

HVDC power transmission systems do not encounter any natural zero crossing unlike the AC systems and hence the DC circuit breakers employed should be fast-acting and reliable to ensure safe operation. Circuit breakers (CB) that have fast response time with lower energy loss dissipation are required for subsea HVDC transmission systems. This paper investigates the performance of various CB topologies including ultra-fast coupled inductor hybrid circuit breaker (CIHCB) topology without and with the integration of resistive type superconducting fault current limiter (R-SFCL) for a 100 kV, 100 MW HVDC transmission systems. It is found that the addition of R-SFCL with 1.7 ms response time decreases the peak current through the breaker and hence the power dissipated in the CB during short circuit fault conditions. Thus, the rating of CB can be significantly decreased with the proposed topology. Further, a comparison of power loss in CIHCB with the existing topologies such as mechanical CB (MCB), resonant CB (RCB) and HVDC-hybrid CB (HVDC-HCB) are also presented in this paper.