DC circuit breaker（DCCB） is a key protective device in voltage-source-converter-based high-voltage DC transmission（VSC-HVDC）. The existing high-voltage DCCBs are mainly divided into two technical routes: the mechanical type based on artificial-current-zero method and the hybrid type based on power electronics devices. Based on a DCCB topology scheme named ‘rapidly energy dissipating hybrid DCCB’

this paper introduces its topological structure and interruption process firstly. After the exploration of requirements for the reclosing time of DCCB

adaptability analysis of the reclosing time is carried out for the scheme

and its drawbacks of inadaptation to fast reclosing are pointed out. Then

three improved topology schemes are formed by adding RC components at different locations in the original scheme

and they are verified and compared by the method of theoretical analysis and simulation analysis. The results show that all of the three improved topologies can largely accelerate the discharging speed of fault side inductor

and therefore can meet the requirements of fast reclosing. Scheme 2 and Scheme 3 are suitable for the occasion of strict demands for current limiting but low demands for cost. Scheme 1 has the best comprehensive effect because it is not only simple and easy but also can greatly accelerate the discharging speed of fault side inductor while only slightly slows down that of the non-fault side.