Topology Simulation and Design of Bidirectional Fault Current Limiter for DC BUS

The fault current of the flexible DC transmission system rises quickly and has a large amplitude, and the existing DC circuit breaker (DCCB) fault cutting speed and breaking capacity have been greatly challenged. Based on this, a DC current limiter based on saturated core and converter branch is proposed, which uses the saturated core and current limiting resistor to jointly act to achieve resistive inductive current limiting, and accelerates the fault current removal and relieves the breaking pressure of DC circuit breaker through energy absorption resistance and auxiliary current limiting branch. Finally, the principle correctness and functional effectiveness of the improved resistance inductive DC current limiting circuit are verified in the PSCAD/EMTDC simulation platform. The results show that the improved resistance inductive DC current limiting circuit can effectively suppress the fault current, quickly isolate the fault line, and reduce the energy absorption pressure of the arrester.