부산대학교 도서관

Fluoronitriles-CO 2 gas mixtures are promising alternatives to SF 6 in environmentallyfriendly gas-insulated transmission lines (GILs). Insulating gas heat transfer characteristics are of major significance for the current-carrying capacity design and operational state monitoring of GILs. In this paper, a three-dimensional calculation model was established for a GIL using the thermal-fluid coupled finite element method. The calculated results showed close agreement with experimentally measured data. The temperature distribution of a GIL filled with the Fluoronitriles-CO 2 mixture was obtained and compared with those of GILs filled with CO 2 and SF 6 . Furthermore, the effects of the mixture ratio of the component gases and the gas pressure on the temperature rise and current-carrying capacity of the GIL were analyzed. Results indicated that the heat transfer performance of the Fluoronitriles-CO 2 gas mixture was better than that of CO 2 but worse than that of SF 6 . When compared with SF 6 , use of the Fluoronitriles-CO 2 gas mixture caused a reduction in the GIL’s current-carrying capacity. In addition, increasing the Fluoronitriles gas component ratio or increasing the pressure of the insulating gas mixture could improve the heat dissipation and current-carrying capacity of the GIL. These research results can be used to design environmentally-friendly GILs containing FluoronitrilesCO 2 gas mixtures.