LAUSR

There are many disadvantages in the conventional method of limiting the short-circuit of the flexible HVdc transmission system such as a series-connecting electric reactor on the dc side. This paper presents a short-circuit current limiting method for adding a resistive-type superconducting fault current limiter. Considering the flexibility of various HVdc operating conditions and short-circuit characteristics, as well as the performance requirements to the superconducting fault current limiter, the system scheme of the 160-kV/1-kA resistive-type superconducting dc fault current limiter was designed, and the system topology and the main parameters of the current limiter were proposed. According to the mutual restriction relationship between the current limiting resistance, the fault current, and the thermal stability, an iterative algorithm for optimizing the fault current–resistance curve was proposed, and the optimal parameters of the solution were obtained. The rationality of the designing scheme for the 160-kV/1-kA resistive-type superconducting dc fault current limiter was verified by the system simulation based on the prototype of the flexible dc transmission system at Nan'ao in Guangdong province proves. This paper provides a new technical solution for the stable operation of the flexible dc transmission system.