Gas-insulated substations

There are a number of papers on nonuniform lines [30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48-49]. EMC-related transients or surges in a gas-insulated substation and on a tower involve nonuniform lines, such as short-line, nonparallel, and vertical conductors. Pollaczek s [7], Caron s [8], and Sunde s [50] impedance formulas for an overhead line are well known and have been widely used in the analysis of the transients mentioned earlier. However, it is not well known that these formulas were derived assuming an infinitely long and thin conductor, that is, a uniform and homogeneous line. Thus, impedance formulas are restricted to the uniform line where the concept of per-unit-length impedance is applicable. 

Gas-insulated bus and cable A cable and a gas-insulated bus are represented either as three single-phase distributed lines with their coaxial mode surge impedance and propagation velocity or as a three phase distributed line system. As a gas-insulated substation involves a significant number of gas-insulated buses/lines, the pipes are, in most cases, eliminated by assuming zero voltage. 

Ametani, A., T. Goto, S. Yoshizaki, and H. Motoyama. 2006. Switching surge characteristics in gas-insulated substation. (JPEG 2006, Newcastle, U.K. Paper 12-19. 

Ametani, A., T. Goto, N. Nagaoka, and H. Omura. 2007. Induced surge characteristics on a control cable in a gas-insulated substation due because of switching operation. lEEJ Trans. PE 127(12) 1306-1312. 

There are a number of papers discussing a nonuniform line [28-47]. EMC-related transients or surges in a gas-insulated substation and on a tower involve the nonuniform line such as a short-line, nonparallel, and vertical... 

FIGURE 13 Totally enclosed metalclad substation using SFs gas as the insulating medium. (Courtesy of Westing-house Electric Corporation.)... 

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