The overvoltage of interrupting off-load transmission line with series-resonant type fault current limiter

Series resonant type fault current limiter (SRFCL) may find earliest applications in power systems; however, its comprehensive impacts on power system need further investigation and verification. On the basis of the equivalent model of SRFCL proposed in this paper, its influence on the interruption overvoltage of 500kV EHV off-load transmission line is studied. With regard to interrupting off-load line, considering different switching times, the terminal overvoltage waveforms of interrupting off-load line with and without installation of SRFCL are analyzed by simulation. If arc doesn't reignite, there will be no influence of SRFCL on the terminal voltage. If not, the interruption overvoltage of off-load line will be suppressed by SRFCL. With consideration of different fault current reactance, the relationships between instantaneous maximum of overvoltage when arc reignites, oscillation period of free component and different fault current limiting reactance are presented. The simulation analysis and theory computation results show that the installation of SRFCL is benefit for interrupting off-load transmission line.