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Performance of transmission lines 1

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Question 19 A (medium) single phase transmission line 100 km long has the following constant , resistance per kilometer 0.25 ohm , reactance per kilometer 0.8 ohm , susceptance per kilometre 14×10–⁶ siemens, receiving end line voltage  66 kv ,  Asuming that the load capacitance of the line is localised at the receiving end alone .  determine (1) the sending end current (2)  the sending end voltage (3)  regulation  {4) supply power factor .  the line is delivering 15000 kilowatt at 0.8 power factor lagging . Draw the phasor diagram to illustrate your calculations  .  Solution   (4) Supply power factor = referring to expression (2)  phase angle between Vr  and Ir  is phy 1 = tan–¹ - 78/227 = (-0.3436) = -18.96° , details  Reffering to expression (2) phase angle between Vr and Vs is , phy 2 = tan–1 16210/77915 = tan–¹(0.2036) = 11.50 ° , details ,  ...