2 decimal places A 200 KVA, single phase two-winding transformer rated 4160/230V, 60 Hz has primary and second impedances of 0.09 + j 0.9 ohmsand 0.02 + j 0.2 ohms respectively. The full-load copper loss ismeasured to be 5000 W during operations. The core loss is 650 Wwhen a voltage of 2200 V, 50 Hz is applied to the transformer and210 W at 1200 V, 25 Hz. Calculate:a.b.C.The core loss at normal operation and the maximumand full-load efficiency both at 0.9 power factor.The percent voltage regulation when connected as anautotransformer, full-load 0.8 power factor lagging. Alsocompute current at the common winding.The two-winding percent regulation when the powerfactor is 0.7 leading.d.If another 100-KVA, 60 hz, single phase is connected inparallel with it to supply a load of 250 KVA, 0.8 powerfactor lagging. The primary and secondary impedancesof the new transformer is 0.085 + j 0.25 ohms and 0.035+j 0.22 ohms respectively.horing of each transformerou

We have to Answer the following questiona. The core loss at normal operation and the maximum and…

A 200 KVA, single phase two-winding transformer rated 4160/ V, 60 Hz has primary and second impedances of 0.09 + j 0.9 ohms and 0.02 + j 0.2 ohms respectively. The full-load copper loss is measured to be 5000 W during operations. The core loss is 650 W when a voltage of 2200 V, 50 Hz is applied to the transformer and 210 W at 1200 V, 25 Hz. Calculate: a. The core loss at normal operation and the maximum and full-load efficiency both at 0.9 power factor. b. The percent voltage regulation when connected as an autotransformer, full-load 0.8 power factor lagging. Also compute current at the common winding. The two-winding percent regulation when the power factor is 0.7 leading. C. in

A 200 KVA, single phase two-winding transformer rated 4160/ V, 60 Hz has primary and second impedances of 0.09 + j 0.9 ohms and 0.02 + j 0.2 ohms respectively. The full-load copper loss is measured to be 5000 W during operations. The core loss is 650 W when a voltage of 2200 V, 50 Hz is applied to the transformer and 210 W at 1200 V, 25 Hz. Calculate: a. The core loss at normal operation and the maximum and full-load efficiency both at 0.9 power factor. b. The percent voltage regulation when connected as an autotransformer, full-load 0.8 power factor lagging. Also compute current at the common winding. The two-winding percent regulation when the power factor is 0.7 leading. C. in

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 3.36P: Three single-phase two-winding transformers, each rated 25MVA,34.5/13.8kV, are connected to form a...

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An infinite bus, which is a constant voltage source, is connected to the primary of the three-winding transformer of Problem 3.53. A 7.5-MVA,13.2-kV synchronous motor with a sub transient reactance of 0.2 per unit is connected to the transformer secondary. A5-MW,2.3-kV three-phase resistive load is connected to the tertiary Choosing a base of 66 kV and 15 MVA in the primary, draw the impedance diagram of the system showing per-unit impedances. Neglect transformer exciting current, phase shifts, and all resistances except the resistive load.
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A single-phase 100-kVA,2400/240-volt,60-Hz distribution transformer is used as a step-down transformer. The load, which is connected to the 240-volt secondary winding, absorbs 60 kVA at 0.8 power factor lagging and is at 230 volts. Assuming an ideal transformer, calculate the following: (a) primary voltage, (b) load impedance, (c) load impedance referred to the primary, and (d) the real and reactive power supplied to the primary winding.
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(a) An ideal single-phase two-winding transformer with turns ratio at=N1/N2 is connected with a series impedance Z2 across winding 2. If one wants to replace Z2, with a series impedance Z1 across winding 1 and keep the terminal behavior of the two circuits to be identical, find Z1 in terms of Z2. (b) Would the above result be true if instead of a series impedance there is a shunt impedance? (c) Can one refer a ladder network on the secondary (2) side to the primary (1) side simply by multiplying every impedance byat2 ?
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