MGVCL Exam Paper (30-07-2021 Shift 3)
A 50 Hz synchronous generator is connected to an infinite bus through a line. The p.u. reactances of generator and the line are j0.4 p.u. and j0.2 p.u. respectively. The generator no load voltage is 1.1 p.u. and that of infinite bus is 1.0 p.u. The inertia constant of the generator is 4 MW-sec/MVA. Determine the frequency of natural oscillations if the generator is loaded to 60% of its maximum power transfer capacity and small perturbation in power is given.

1.8 Hz
1.2 Hz
0.8 Hz
1.6 Hz

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MGVCL Exam Paper (30-07-2021 Shift 3)
The DC offset in fault current causes conventional over-current (OC) relays to :

sometimes under-reach and sometimes over-reach
reach remains unaffected due to DC offset
over-reach
under-reach

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MGVCL Exam Paper (30-07-2021 Shift 3)
In a 3-phase, 4-wire, 400/230 V system, a lamp (L₁) of 100 W is connected to one phase and neutral and a lamp (L₂) of 150 W is connected to the second pahse and neutral. If the neutral wire is disconnected accidently, what will be the voltage across a 150 W lamp (L₂)?

180 V
240 V
120 v
160 V

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MGVCL Exam Paper (30-07-2021 Shift 3)
If the power supplied by current source shown in figure is double of that supplied by the voltage source, then the value of 'R' is

3.33 Ω
7.5 Ω
5 Ω
2.5 Ω

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