| Title |
An Evaluation Method for Short-Term Ratings of Double-Circuit Overhead Transmission Lines |
| Authors |
Sung Duck, Kim ; Hong-Kwan Sohn ; Tae-In Jang |
| Keywords |
Double-Circuit ; Overhead Transmission ; Short-term Ratings ; Dip and Clearance |
| Abstract |
This paper describes an analytical method to determine the short-term ratings to reliably operate the overhead transmission lines with double-circuit lines when faulting one circuit of the two. As linearizing the thermal equilibrium equation that represents the temperature characteristic of conductors, we show that the linear equation can be easily presented the over-current and it"s temperature property during overloading the one line. Generally, it is well known that the short-term line ratings should be determined by considering both conductor life and dip. However, most power companies have their own different guides for the short-term ratings. Using the suggested method in this paper, it can be re-accessed the short-term ratings given in Kepco"s overhead transmission lines constructed during the past three different periods. As a result, it is verified that the short-term ratings could be increased more efficiently. Furthermore, it would be directly applied the given method to determine the short-term dynamic line ratings when occurring faults in one of the double-circuit lines, without doing any other actions for the current lines. |