344. Consider the following statements : Transient stability of a synchronous generator feeding power to an infinite bus through a transmission line can be increased by

A.I. increasing the steam supply the turbine driving the generator during clearing.triangle with sides equal to 'd', then the

B.(a) capacitance and the inductance will increase

C.(b) capacitance will increase and the inductance will decrease

D.(c) capacitance and the inductance will remain the same

345. An overhead transmission line having surge impedance `Z1' is terminated to an underground cable of surge impedance The reflection coefficient for the travelling wave at the junction of the line and cable is

A.Z1 -1- Z2

B.ZI ?Z2 Z2 ? Z1

C. Z1 + Z2

D. Z1 + Z2

346. Ring main distribution is preferred to a radial system because

A. voltage drop in the feeder is less and supply is more reliable

B. voltage-drop in the feeder is less and power factor is high

C. power factor is high and supply is more reliable

D. power factor is high and system is less expensive

347. If the fault current is 3000 A for a relay with a plug setting of 50% and CT ratio of 1000 : 1, the plug setting multiplier would be

A.1.5

B.3

C.4.5

D.6

348. In terms of plant powers P. and P. and loss coefficients Binn, the total transmission loss 'Pi' isN

A. E E Binn Pnm=1 n=1N

B. E E Pm Bmn m=1 n=1N

C. EE PmBmn Pn m=1 n=1N

D. E E 2Pm B m=i n=1

349. The average value of dc voltage of a single-phase semiconverter under continuous conduction is

A.NEV(1 + cosa)

B.NEV(1 ? cosa)

C. V(1 +-cosa)

D.JV(1 ? cosa)

350. The reactance of a generator designated X" is given as 0.25 pu based on the generator's name plate rating of 18 kV, 500 MVA. If the base for calculations is changed to 20 kV, 100 MVA, the generator reactance X" on new base will be

A. 1.025 pu

B. 0.05 pu

C. 0.0405 pu

D. 0.25 pu

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