01․ Transmission line parameters of the short transmission line are

ABCD or transmission line parameters:
V

_{s}= AV_{r}- BI_{r}I_{s}= CV_{r}- DI_{r}Where, V_{s}= Sending end voltage V_{r}= Receiving end voltage I_{s}= Sending end current I_{r}= Receiving end current For short transmission line, line capacitance is neglected. Therefore, I_{r}= -I_{s}, i.e., C = 0 and D = 1 V_{s}= V_{r}+ Z Is i.e., A = 1 and B = Z02․ Which of the following statements is/are true

Voltage regulation = (V

_{rnl}- V_{rfl})/V_{rfl}V_{rnl}= No load receiving end voltage V_{rfl}= full load receiving end voltage V_{s}= AV_{r}+ BI_{r}At no load I_{r}= 0 V_{s}= A Vrnl V_{rnl}= V_{s}/A, V_{rfl}= V_{r}For short transmission line A = 1, therefore, V_{rnl}= V_{s}Voltage regulation for short transmission line = (V_{s}- V_{r}) / V_{r}03․ The ABCD constants of a 3-phase transmission line are
A = D = 0.8∠1°, B = 170∠85° Ω , C = 0.002∠90.4° â„§.
The sending end voltage is 400 kV. The receiving end voltage under no load condition is

ABCD parameters
V

_{s}= AV_{r}+ BI_{r}I_{s}= CV_{r}+ DI_{r}Where, V_{s}= Sending end voltage V_{r}= Receiving end voltage I_{s}= Sending end current I_{r}= Receiving end current Under no load condition, I_{r}= 0 400 = 0.8∠1° * V_{r}V_{r}= 500∠-1° kV04․ Surge impedance loading of a 3-phase, 400 kV transmission line is 400 Ω. The surge impedance loading is

Where,
V

_{ph}= Phase voltage I_{ph}= Phase current V_{l}= Line voltage Z_{s}= surge impedance05․ Surge impedance loading of a transmission line can be increased by

Where,
V

_{ph}= Phase voltage I_{ph}= Phase current V_{l}= Line voltage Z_{s}= surge impedance Therefore, SIL can be increased by increasing its voltage level. Z_{s}can be decreased by the addition of lumped capacitance in series which reduces the effective reactance of the line resulting into higher SIL.06․ For transmission line which one of the following relation is true?

For transmission line,
Symmetry network A = D
Reciprocity network AD - BC = 1

07․ A 3-phase transmission line has its conductors at the corners of an equilateral triangle with side 3m. The diameter of each conductor is 1.63 cm. The inductance of the line per phase per km is

Inductance of a transmission line
Where,
d = distance between the conductors = 3m
r' = 0.7788 r

08․ For some given transmission line the expression for voltage regulation is given by (V

_{s}- V_{r})/V_{r}*100%. Hence,Voltage regulation = (V

_{rnl}- V_{rfl})/V_{rfl}V_{rnl}= No load receiving end voltage V_{rfl}= full load receiving end voltage V_{s}= AV_{r}+ BI_{r}At no load I_{r}= 0, V_{s}= A V_{rnl}V_{rnl}= V_{s}/A, V_{rfl}= V_{r}For short transmission line A = 1, therefore, V_{rnl}= V_{s}Voltage regulation for short transmission line = (V_{s}- V_{r})/V_{r}09․ The capacitance of an overhead transmission line increases with

Capacitance of a transmission line
Where, h = height of conductors above ground
r = radius of the conductors
ε = permittivity
Therefore, as the height of the conductor increases from the ground, the capacitance will also decrease.
Where A = area
d = geometrical mean distance
Therefore, as an increase in mutual geometrical mean distance, the capacitance will decrease.
Therefore, both statements are wrong statements.

10․ The charging reactance of 50 km transmission line is 1500 Ω. What is the charging reactance for 100 km length of line?

Charging reactance X

_{c}= 1/ωC ∝ 1/ length as C ∝ length Charging reactance is inversely proportional to length of the trasnmission line. Therefore, new charging reactance<<<89101112>>>