Characteristics of Gas Insulated Transmission Lines Bonded at Both Ends in Relation to Short-Circuit Forces

Experiments and analysis of the ability of gas insulated transmission lines (GIL) to withstand short-circuit electro-magnetic forces are reported. In order to investigate the effect of short-circuit force on certain parts, special test units of 154kv and 275kV rated GIL were constructed for the tests. No problems occurred with these parts in the tests under short-circuit current up to 20% larger than the specified value. Equations for calculation of short-circuit forces in GIL bonded at both ends were derived and compared with the test results. Further calculations were performed under various conditions which might occur in commercial lines.