Influence on Power Frequency Over-Voltage by Employing Series Resonance Type Fault Current Limiter

The series resonance type fault current limiter (SRFCL) is the most prospective one that can be applied in power grid at present. The influence of SRFCL on power frequency over-voltage in 220 kV power grid was studied. Analysis and calculation results showed that the SRFCL has no distinct impact on the power frequency over-voltage caused by capacitive effect of no-load long transmission lines, but it could reduce the over-voltage caused by unbalanced short-circuits. However, the over-voltage caused by load sheding would increase if SRFCL was employed. When the SRFCL with a 15 Omega limiting reactance was installed at the transmission line of 300 km, the power frequency over-voltage caused by load sheding would increase from 1.28 p.u. to 1.41 p.u., which exceeded 1.40, the allowable value of National Standard. This problem should be solved before the SRFCL was employed in power grid.