337. The p.u. parameters for a 500 MVA machine on its own base are :inertia, M =20 p.u.; reactance, X = 2 p.u. The p.u. values of inertia and reactance on 100 MVA common base, respectively,are
A. 4, 0.4
B. 100,10
C. 4, 10
D. 100, 0.4
338. An 800 kV transmission line has a maximum power transfer capacity of P. If it is operated at 400 kV with the series reactance unchanged, then new maximum power transfer capacity is approximately
A. P
B. 2P
C. P/2
D. P14
339. The insulation strength of an EHV transmission line is mainly governed by
A. load power factor
B. switching over-voltages
C. harmonics
D. corona
340. High Voltage DC (HVDC) transmission is mainly used for
A. bulk power transmission over very long distances
B. inter-connecting two systems with the same nominal frequency
C. eliminating reactive power requirement in the operation
D. minimizing harmonics at the converter stations
341. The inducatance per unit length of an overhead line due to internal flux linkages
A. deends on the size of the conductor
B. is independent of the size of conductor and constant
C. depends on the current through the conductor
D. depends on distance between conductors
342. A single-phase ac distributor supplies two single-phase loads as shown in the given figure. 1.The voltage drop from A to C is j 2. connecting resistors at there enerator terminals during fault conditions.3. employing a faster excitation system.4. quickly throwing off the generator load. Which of these statements are correct?
A. 2 and 3
B. 3 and 4
C. I and 2
D. 2 and 4
343. A synchronous generator with a synchronous reactance of 1.3 pu is connected to an infinite bus whose voltage is 1 pu, through an equivalent reactance of 0.2 pu. For maximum output of 1.2 pu, the alternator emf must be
A. 1.5 pu
B. 1.56 pu
C. 1.8 pu
D. 2.5 pu
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