The effect of frequency on the resistance and internal inductance of bare ACSR conductors

An experimental investigation of the effects of varying the frequency on the electrical characteristics of a 54/19 ACSR (aluminum conductor, steel reinforced) conductor is described. Current from a sine wave alternator with precise voltage and frequency controls in the range 25 to 60 Hz was supplied to a pair of parallel tensioned lengths of the conductor, forming a loop within a nonmagnetic enclosure. The DC and AC resistances, the internal inductive reactance, the axial magnetic flux, the surface current density, and the temperature of the conductor were found. The AC-to-DC with resistance ratio was found to increase with increasing current and increasing frequency. The surface current density decreased with increasing current and increasing frequency. All these variations can be attributed to the transformer effect, resulting from the presence of the steel core and the spiraling of the layer currents, and the increase of magnetic power loss.<
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