Question

A three-phase, 60-Hz, completely transposed 345-kV, 200-km line has two 795,000-cmil (403-mm2) 26/2 ACSR conductors per bundle and the following positive-sequence line constants: z 0.032 + 10.35 /km y j4.2 x 10-6 S/km Full load at the receiving end of the line is 700 MW at 0.99 p.f. leading and at 95% of rated voltage. Assuming a medium-length line, determine the following:
a. ABCD parameters of the nominal π circuit
b. Sending-end voltage Vs, current Is, and real power Ps
c. Percent voltage regulation
d. Transmission-line efficiency at full load

Answer 1

Answer:

B) sending end voltage : Vs-l-l = 345.8 ∠ 26.14⁰ kv

    sending end current : Is = 1.241 ∠ 15.5⁰ KA

    real power = 730.5 Mw

C) percent voltage regulation = 8.7%

D) Transmission line efficiency  = 95.8%

Explanation:

attached is the detailed solution to the problem

Given data:

l = 200 km

z = 0.032 + j0.35 Ω/km

y = j4.2 * 10^-6 S/km

A) find the total series impedance and shunt  admittance

B) sending end voltage : Vs-l-l = 345.8 ∠ 26.14⁰ kv

    sending end current : Is = 1.241 ∠ 15.5⁰ KA

    real power = 730.5 Mw

C) percent voltage regulation = 8.7%

D) Transmission line efficiency  = 95.8%