Q6- the open circuit and short circuit tests on a 10 KVA, 125/250 v, 50 Hz single phase transformer gave the following results: O.C. Test: 125 V,0.6 A, 50 W ( on L.V.) S.C. Test: 20 V, 40 A, 177.78 W (on H.V. side) Calculate: i) Copper losses on half load ii) Full load efficiency at 0.8 leading p.f. iii) Half load efficiency at 0.8 leading p.f. iv) Regulation at full load at 0.9 leading p.f. Ans: 44.445 W, 97.23%, 97.69%, -1.8015%

Q6- the open circuit and short circuit tests on a 10 KVA, 125/250 v, 50 Hz single phase transformer gave the following results: O.C. Test: 125 V,0.6 A, 50 W ( on L.V.) S.C. Test: 20 V, 40 A, 177.78 W (on H.V. side) Calculate: i) Copper losses on half load ii) Full load efficiency at 0.8 leading p.f. iii) Half load efficiency at 0.8 leading p.f. iv) Regulation at full load at 0.9 leading p.f. Ans: 44.445 W, 97.23%, 97.69%, -1.8015%

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 3.11MCQ: For a short-circuit test on a 2-winding transformer, with one winding shorted, can you apply the...

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Similar questions

For a short-circuit test on a 2-winding transformer, with one winding shorted, can you apply the rated voltage on the other winding? (a) Yes (b) No
In developing per-unit circuits of systems such as the one shown in Figure 3.10. when moving across a transformer, the voltage base is changed in proportion to the transformer voltage ratings. (a) True (b) False
An ideal transformer has no real or reactive power loss. (a) True (b) False
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Consider an ideal transformer with N1=3000andN2=1000 turns. Let winding 1 be connected to a source whose voltage is e1(t)=100(1| t |)volts for 1t1ande1(t)=0 for | t |1 second. A2- farad capacitor is connected across winding 2. Sketch e1(t),e2(t),i1(t),andi2(t) versus time t.
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A bank of three single-phase transformers, each rated 30MVA,38.1/3.81kV, are connected in Y- with a balanced load of three 1, Y-connected resistors. Choosing a base of 90MVA,66kV for the high-voltage side of the three-phase transformer. spify the base for the low-voltage side. Compute the per-unit resistance of the load on the base for the low-voltage side. Also, determine the load resistance in ohms referred to the high-voltage side and the per-unit value on the chosen base.
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For developing per-unit equivalent circuits of single-phase three-winding transformer, a common Sbase is selected for all three windings and voltage bases are selected in proportion to the rated voltage of the windings (a) True (b) False
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For an ideal 2-winding transformer, the ampere-turns of the primary winding, N1I1 is equal to the ampere-turns of the secondary winding, N2I2 (a) True (b) False