Temperature Distribution within ACSR Conductor During Large Current Flow

In this paper, the temperature distribution within ACSR conductor was precisely measured and examined, conducted as part of a series of studies on large currents in transmission line. The study results may be summarized as follows. (1) The temperature difference within the conductor cross-section increases as the square of the current; however, even at a current equal to 50% more than the allowable current, the maximum temperature difference within the aluminum components is from 5°C (ACSR 410 mm2) to 6°C (ACSR 810 mm2). (2) The results of measurements of the conductance between outer-layer and inner-layer aluminum strands in the conductor, and analysis of the current distribution in the inner and outer layers, indicated that even if the conductance were to drop sharply to 10, 000S/m, any inhomogeneity or concentration in the current distribution at a conductor connection joint has disappeared by 1.5m or so from the tip of the joint. (3) According to measurements of the conductor temperature near a joint, the electrical resistance of the joint is lower than that of the same length conductor, so that the conductor temperature falls for 0.5m or so from the tip of the joint. (4) Based on the above findings, the temperature distribution within an ACSR conductor accompanying the passage of large currents can be regarded as nearly uniform both across the conductor cross-section, and in the conductor length direction.