351. The severity of line to ground and three-phase faults at the terminals of an unloaded synchronous generator is to be = Z2= j0.1 pu and Z0 = j 0.05 pu for Z2 ZI + Z2 the alternator, then the required inductive reactance for neutral grounding is
A. 0.0166 pu
B. 0.05 pu
C. 0.1 pu
D. 0.15 pu
352. The surge impedance loading of a long transmission line can be increased without adversely affecting its stability by connecting
A. lumped inductances in series with the line
B. lumped inductances in shunt with the line
C. lumped capacitances in shunt with the line
D. lumped capacitances in series with the line
353. A transmission line has equal voltages at the two ends, maintained constant by two sources. A third source is to be provided to maintain constant voltage (equal to the end voltages) at either the mid-point of the line (case 1) or at 75% of the distance from the sending end (case 2). Then the maximum power-transfer capabilities of the line in the original case, case 1 and case 1, respectively, will be in the ratio of
A. 1 : 1 : 1
B. 1 :2 :1/0.75
C. 1 : 2 : 4
D. 1: 4: 16
354. A short length of cable is connected between dead-end tower and sub-station at the end of a transmission line. Which of the following will decrease, when voltage wave is entering from overhead line to cable?1. Velocity of propagation of voltage wave.2. Steepness of voltage wave.3. Magnitude of voltage wave.Select the correct answer using the codes given below :Codes :
A. 1 and 2
B. 2 and 3
C. 3 and 1
D. 1, 2 and 3
355. The corona contributes a 3rd harmonic to the charging current of the line,because it. occurs every half cycle of the fundamental frequency
A. induces a 3rd harmonic voltage between line and earth
B.(e) produces random harmonics, but only 3rd harmonic is passed through the line capacitance.
C.(f) affects the system grounding for which a 3rd harmonic voltag appears on the line, and causes 3rd harmonic charging current.
D.
356. In load flow analysis, the load at a bus is represented as
A.. a constant current drawn from the bus
B. a constant impedance connected at the bus
C. constant real and reactive powers drawn from the bus
D. a voltage-dependent impedance at the bus
357. Shunt resistor is connected across the contacts of a circuit-breaker in order to
A. damp out the restriking transient
B. bypass the are current
C. limit the short-circuit current
D. reduce the damage to the contacts due to arcing
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