4. A transformer is rated 1000 MVA, 13.8 kV/345 kV with Z=j0.10 pu. If the system base MVA is 500, the corresponding puimpedance becomes(a) j0.10/2 pu(b) j0.10/4 pu(c) j0.10*2 pu(d) j0.10*4 pu5. Ia, Ib and I, are the three current phasors of a load. For a balanced-load condition, which relation is valid?(a) IF - (Ib + I.)(c) la + I = 1.(d) Ia - I = I.(b) la = I, = Ie

(4) Given that Zpu old=j.10 MVAb old=1000KVb old=13.8KVMVAb new=500 Assume that the new base voltage…

A transformer is rated 1000 MVA kV/345 kV with Z-70.10 pu. If the system base MVA is 500, the corresponding pu impedance becomes (a) j0.10/2 pu (b) j0.10/4 pu (c) J0.10*2 pu (d) J0.10*4 pu 5. Ia, Is and I, are the three current phasors of a load. For a balanced-load condition, which relation is valid? (a) L- - (Is + 1) (b) I. = I, = Ie (c) L + Is = I. (d) I, - Is = Ie

A transformer is rated 1000 MVA kV/345 kV with Z-70.10 pu. If the system base MVA is 500, the corresponding pu impedance becomes (a) j0.10/2 pu (b) j0.10/4 pu (c) J0.102 pu (d) J0.104 pu 5. Ia, Is and I, are the three current phasors of a load. For a balanced-load condition, which relation is valid? (a) L- - (Is + 1) (b) I. = I, = Ie (c) L + Is = I. (d) I, - Is = Ie

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.4P: A single-phase 100-kVA,2400/240-volt,60-Hz distribution transformer is used as a step-down...

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