A Novel I-SFCL Concept for Application in Flexible DC Grid Considering the Operation Stability

DC fault current limitation is the key technique to improve the reliability and security of flexible dc grid operation. But the traditional dc fault current limiting method, which directly installs inductor in dc grid, will seriously deteriorate transient response ability and operation stability of the dc grid. In this paper, a simple I-SFCL topology is proposed. According to the theoretical analysis, the I-SFCL has similar ability of limiting dc fault current compared with the method directly installing dc inductor. And it can effectively eliminate negative effect of dc inductor on system transient response ability and operation stability. Finally, the simulation cases based on PSCAD/EMTDC proves the correctness of theoretical analysis and superiority of the proposed I-SFCL.