LINE CONSTANT MEASUREMENT METHOD FOR PARALLEL TWO-LINE POWER TRANSMISSION LINE AND PROTECTION CONTROL MEASUREMENT APPARATUS

• Main Authors: KATO MASAHIRO, HISAKADO TAKASHI, UMEZAKI HIROYUKI, KOBAYASHI KENTARO, KAGAMI TOSHIRO
• Format: Patent
• Language: English
• Published: 15.03.2012
• Subjects: MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PHYSICS; TESTING

PROBLEM TO BE SOLVED: To easily and accurately calculate a line constant of a parallel two-line power transmission line.SOLUTION: There are provided: a protection control measurement apparatus 110 for fetching electric quantities of parallel two-line power transmission lines 101A-101C and 102A-102C to be measured to both ends thereof; time synchronizing means 112 for fetching electric quantities at the same time in the protection control measurement apparatus 110 in both the ends; and line constant calculating means 113 for calculating a constant of the lines from the electric quantities fetched from the protection control measurement apparatus 110 in both the ends. The line constant calculating means 113 handles a power transmission line of parallel two lines as a power transmission line model of one line by mode-decomposing the power transmission line into a common mode and a differential mode, and restores the line constant calculated as two one-line power transmission line models to a parallel two-line power transmission line model through mode combination, thereby calculating the line constant of the parallel two-line power transmission line.