Impact of the Inductive FCL on the Interrupting Characteristics of High-Voltage CBs During Out-of-Phase Faults

With respect to power systems installed with inductive fault current limiters (FCLs), the impact of an FCL on the out-of-phase fault current level was first analyzed, and thereby a method for determining the critical length of the power transmission tie lines was also given. Based on theoretical analysis and deduction, strict mathematical formulas were obtained to properly describe the relationship between the current limit factor and the recovery voltage of a circuit breaker (CB) as well as the rate of rise of recovery voltage (RRRV). Further, the concrete impacts of an FCL on the maximum and the RRRV of the recovery voltage were analyzed. Regarding out-of-phase faults, a conception of interruption severity as well as its quantitative expression for CBs was introduced, and a formula was established to incorporate the influence from the current limit factor and stray capacitance on the interruption severity of CBs, subsequently followed by detailed investigations. The aforementioned proposed research presents analytical methodology and practical reference for the parameter optimization of the inductive FCL and reliable selection of the interrupting characteristics of the high-voltage CBs.