MGVCL Exam Paper (30-07-2021 Shift 2)
A generating station having 'n' section busbars each rated at Q kVA with ×% reactance is connected on the tie-bars systems through busbar reactances of b%. Determine the short circuit kVA if a 3-phase fault takes place on one section.

Q[(1/x) - (n+1)/(bn-x)]
Q[(1/x) + (n-1)/(bn+x)]
Q[(1/x) + (n+1)/(bn+x)]
Q[(1/x) + (n+1)/(bn-x)]

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 2)
The expression for voltage regulation of a short transmission line for leading power factor is given by: ____, where, 'I' is the line current, 'V_r' is the receiving end voltage, 'R' is the line resitance and 'X' is the line reactance.

(IXcosφ_r - IRsinφ_r)/V_r
(IRcosφ_r - IXsinφ_r)/V_r
(IXcosφ_r + IRsinφ_r)/V_r
(IRcosφ_r + IXsinφ_r)/V_r

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 2)
If no load is connected to solar PV system,

it will stop absorbing light
it will dissipate energy in the panel and increase its temperature
it will start reflecting the light
its voltage will go on increasing till its breakdown

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 2)
The line currents in amperes in phases a, b and c respectively are 500 +j150, 100 – j600 and – 300 + j600 referred to the same reference vector with phase sequence of abc. Find the symmetrical component of currents.

Ia₀ = (100+j50) AIa₁ = (146.41+ j65.47) AIa₂ = (546.41-j165.47) A
Ia₀ = (100+j50) AIa₁ = (546.41+ j165.47) AIa₂ = (546.41-j165.47) A
Ia₀ = (100+j50) AIa₁ = (200+ j107.75) AIa₂ = (200-j107.75) A
Ia₀ = (100+j50) AIa₁ = (546.41+j165.47) AIa₂ = (-146.41-j65.47) A

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 2)
Interposing current-transformer (CT) is used in differential protection of a transformer to

limit the main CT secondary current
match the standard ratio of CTs used on both sides of the transformer winding
increase the sensitivity of the relay
minimize the effect of saturation of the main CTs

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP