01․ The positive (Z

_{1}), negative (Z_{2}) and zero sequence (Z_{0}) impedances of a transmission line follows the relationZero sequence impedance Z

_{0}= Z_{s}+ 2 Z_{m}Positive sequence impedance Z_{1}= Negative sequence impedance Z_{2}= Z_{s}- Z_{m}Therefore, (Z_{1}= Z_{2}) < Z_{0}In general zero sequence current is three or four times of the positive or negative sequence impedance of the line.02․ Peterson coil is used in case of transmission line for

In case of ground faults LG and LLG, arcing grounds are produced, this will cause charging current of the capacitor increase and hence voltage of the healthy phases are raised to dangerous limits, at which insulation failure of healthy phases occurs.
To compensate this effect an inductive coil called 'Peterson coil' is connected between ground and the neutral.
The value of inductance used for compensation of arcing grounds = 1/3ω²C

03․ Which of the following represents the transmission line positive sequence reactance

For a transmission line,
Zero sequence impedance Z

_{0}= Z_{s}+ 2 Z_{m}Positive sequence impedance Z_{1}= Negative sequence impedance Z_{2}= Z_{s}- Z_{m}04․ High capacity generators and motors are of

In case of delta network, there is no path for zero sequence currents because there is no ground return and hence considered zero sequence currents are circulating within the winding.
High capacity generators and motors of star connected with grounding is practically used for faster identification of faults and to isolate the faulty section.

05․ Which of the following statements is/are true?
In case of parallel transmission lines

If the fault is very nearer to the substation or generator, the reactance of the network is small. So that fault current is larger.
Fault current I

_{f}∝ 1/X (inversely proportional to reactance) Where X = Reactance of the network Therefore, compare to the single transmission line, parallel line or double line has low reactance. So that the fault current is more in the case of parallel lines. As load angle is directly proportional to transmission line reactance value, load angle is less for parallel lines, this will increases the stability of the transmission line.06․ The positive, negative and zero sequence per unit impedance of two generators connected in parallel are X

_{1}= 0.12 pu, X_{2}= 0.096 pu and X_{0}= 0.036 pu. For LG fault at generator terminals (with 1 pu voltage) the positive sequence current will beFor LG fault at generator terminals, the positive sequence current
I

_{R1}= V/(X_{1}+X_{2}+X_{0}) Since, two generators with same X_{1}, X_{2}and X_{0}are connected in parallel,07․ The VSWR of transmission line is

08․ The SWR on a lossless transmission line of the characteristic impedance 100 ohm is 3. The line is the terminated by

For a transmission line, reflection co-efficient,
Here Z

_{L}= 3 00 Γ_{L}= 200/400 = ½ and SWR = 3.09․ For a line characteristic impedance z

_{o}terminated is load z_{o}/3, the reflection coefficient isZ

_{L}= Z_{0}/3,10․ If R = 84 ohm/Km, G = 10

^{-6}mho/Km, H = 0.01 H/Km, C = 0.061 μ F/Km and frequency = 1000 Hz, then what is the value of propagation constant of the transmission line<<<3233343536>>>