The Simulation Model Of Sfcl And Its Cooperation With Circuit Breaker

With the continuous improvement of short circuit current in our country, the short circuit current of some areas has exceeded the breaking capacity of the circuit breaker. The SFCL can be applied to the short-circuit fault limiting current, which can quickly limit the short circuit current to breaking current, so that the circuit breaker can cut off the circuit successfully. This is especially important in the DC transmission system. In this paper, the running mechanism of DC SFCL and the process of quench of superconductivity are analyzed, and the thermal and electrical models of SFCL are established. Based on superconducting characteristics, PSCAD is used to set up a custom model for the SFCL. Then the current limiting process of the cooperation with circuit breaker is analyzed, and the whole process of occurrence and removal of faults in 4KV DC transmission system is simulated in PSCAD. In simulation, this paper studies the characteristics of SFCL and circuit breakers under different parameters, and obtains the demand for the relationship between the limiting effect and the blocking capacity, and lays a foundation for the research on the cooperation between the SFCL and the breaker.