[1] (a) A completely transposed 60-Hz three-phase line has flat horizontal phase spacing with 10 m between adjacent conductors. The conductors are 1,590,000 cmil ACSR with 54/3 stranding (GMR = 0.0159 m). Line length is 200 km. Determine the inductance in H and the inductive reactance in ?. (b) Each of the 1,590,000 cmil conductors in (a) is replaced by two 795,000 cmil ACSR 26/2 conductors (GMR = 0.0114 m), as shown in Figure. Bundle spacing is 0.40 m. Flat horizontal spacing is retained, with 10 m between adjacent bundle centers. Calculate the inductive reactance of the line and compare it with that of (a) (c) For the three-phase line in (b), determine the capacitance-to-neutral in F and the shunt admittance-to-neutral in S. If the line voltage is 345 kV, determine the charging current in kA per phase and the total reactive power in Mvar supplied by the line capacitance. Assume balanced positive-sequence voltages. (r = 0.0141 m)
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The formula for inductance of a three-phase line is given by: L = 2 * 10^-7 * ln(D/r) where D is the distance between the conductors and r is the GMR of the conductor. Substituting the given values, we get: L = 2 * 10^-7 * ln(10/0.0159) = 1.26 * 10^-3 Show more…
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