Q1.) While modeling the power system to pu values; Base MVA selected is
Largest equipment MVA
MVA rating for maximum number of equipment
Only 100 MVA
Any value but generaly 100 MVA
Q2.) For transformer PU value as seen from HV and LV-
HV is more than LV
LV is more than HV
Both equal
Depends up on capacity and voltage ratio
Q3.) While modeling the power system-
Always neglect source impedance
Never neglect source impedance
Source impedance may be neglected for approximate calculations
Source impedance may be neglected depending upon situation
Q4.) For fault level calculations; zero sequence impedance of transmission line is-
Approximatly 3 times of its +Ve sequence impedance
3 times of its +Ve sequence impedance
Changes largly depending upon line construction and other parameters
Can be calculated from +Ve and -Ve sequence impedance
Q5.) For fault level calculations; synchronous generators are represented by-
Direct axis sub-transient reactance
Direct axis transient reactance
Direct axis steady state reactance
Quadrature axis sub-transient reactance
Q6.) While modeling the power system for fault current calculations, resistance of the line-
Always neglected
Sometimes neglected
Considered as 1/5th of reactance
Always considered
Q7.) While calculating PU impedance of the 132kV line base kV will be
132/sqrt(3)
132kV
Considered for the system
None from this
Q8.) While modeling transformer; its PU value compared to name plate PU will be-
Remains un-altered irrespective of Base MVA
More if Base MVA more than transformer capacity
>Less if Base MVA more than transformer capacity
Proprtionate to Base MVA
Q9.) To convert 1-ph short circuit MVA at 132kV level to corresponding current multiply short circuit MVA by-
4.375
4.375/sqrt(3)
4.375*sqrt(3)
None from this
Q10.) For 33/11kV Dy11 transformer for LV side SLG fault HV side current will be
3 times less than LV
3 times more than LV
5.2 times less than LV
None from this
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