GETCO EE Practice Quiz-38

For a 100 MVA, 12 KV transmission line of reactance value of 1.20 Ω. The pu value of reactance is:

For the power system shown in the figure below, the specification of the components is following:

G₁ = 40 kV, 100 MVA, X = 10%

G₂= 40 kV, 50 MVA, X = 10%

T₁= 40 KV/120 kV, 150 MVA, X = 15%

T₂= 120 kV/40 kV, 150 MVA, X = 15%

Line: 120 KV, X = 150 ohms

Choose 40 KV as base voltage at the generator G₁ and 100 MVA as base MV

For 100 MVA, 15 KV, 3-phase generator. The short circuit current is 50%. What will be the actual value of short circuit current?

An alternator is rated at 110 MVA, 11 kV, X = 10 Ω. Then the reactance (in p.u.) for 220 MVA, 22 kV is ___________.

For given base voltage and base volt-amperes, the per unit impedance value of an element is x. What will be the per unit impedance value of this element when the voltage and volt-ampere bases are both doubled?

A 10 MVA, 20 KV/50 KV, Y-Y transformer has a pu impedance of 10% an HV side. The impedance value at LV side will be.

A 3 phase transformer is rated 400 MVA,220/22KV Y/∆.The short circuit reactance measured on the low voltage side of the transformer is 0.121Ω.The per unit reactance of a transformer and the value to be used represent the transformer in a system whose base on high voltage side of transformer is 100MVA and 230 KV.

In a single-line diagram, equivalent representation of transformer is.

For the power system as shown below, the zero-sequence impedance as seen from point ‘P’ and ‘Q’ respectively are:

A 3-ϕ fault occurs at the middle of transmission line at point F. The generator having reactance X_d^’’ = 0.29 p.u. and each transformer having X = 0.1 p.u. & each transmission line having reactance of X = 0.3 p.u. Find the transfer reactance between generator and infinite bus?