MGVCL Exam Paper (30-07-2021 Shift 1)
Determine the ohmic value of the current limiting reactor per phase external to a 30 MVA, 11 kV, 50 Hz, three phase synchronous generator which can limit the current on short circuit of 5 times the full load current. The reactance of the synchronous generator is 0.05 pu.

0.305 Ω
0.605 Ω
0.805 Ω
0.405 Ω

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 1)
Determine maximum permissible load which a 15 MVA, ONAN cooled transformer to IS : 2026 can take for 6 hr, if the initial load on it was 12 MVA. The weighted ambient temperature is 20˚C. Assume the permissible load kVA as a fraction of rated kVA is 1.25.

15 MVA
12 MVA
18.75 MVA
9.6 MVA

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 1)
The necessary equation to be solved during the load flow analysis using Fast-Decoupled methid is given below:
where B' and B'' are formed using the imaginary part of the bus admittance matrix Ybus, n is the total number of buses in the system, m is the number of voltage regulated buses. The size of matrix B' is
∆P/|Vi|= -B' ∆δ
∆Q/|Vi| = -B'' ∆|Vi|

(n-m) x (n-m)
(m-1) x (m-1)
(n-1) x (n-1)
(n-m-1) x (n-m-1)

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP