4. An Open-Wye/Open-Delta transformer, as shown in Figure, is formed by two identical single-phase transformers. The primary line-to-line voltage is 12.47 kV, and the secondary line-to-line voltage is 208 V. Take

4. An Open-Wye/Open-Delta transformer, as shown in Figure, is formed by two identical single-phase transformers. The primary line-to-line voltage is 12.47 kV, and the secondary line-to-line voltage is 208 V. Take

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 3.63P: A 23/230-kV step-up transformer feeds a three-phase transmission line, which in turn supplies a...

See similar textbooks

Related questions

Q: True or False? Consider a 3 phase transformer with same line to line voltage ratio. The delta…

A: Delta to Delta transformer: The primary phase current is,I1=13IL1The secondary phase currennt…

Q: Consider Figure 1 of the text. For an ideal phase-shifting transformer, the impedance is unchanged…

A: Referring to the given hints, the impedance of the secondary side seen from the primary side:

Q: If the open circuit voltage is 239V and the full load voltage is 205V, then the percentage…

A: Voltage Regulation is nothing but ratio of drop in voltage from no load to full load to full load…

Q: If the open circuit voltage is 225V and the full load voltage is 200V, then the percentage…

Q: For an ideal 2-winding transformer, an impedance Z2 connected across winding 2 (secondary) is…

A: For a 1-phase transformer, the basic relation is given as:

Q: Describe the On-load and No-load in transformers

A: On-load in transformer Current flows through the secondary winding and out to the load when an…

Q: Example 1: A single-phase, 100-kVA, 1000:100-V, 60-Hz transformer has the following test results:…

Q: where a dashpot mechanism is employed in a constatant-current transformer, it is used as a…

Q: Consider the following short circuit transformer as shown in figure below which operate at: the…

A: The solution is given below

Q: "Under saturated core condition, transformer become a source of harmonics" True False

A: In this question , we will write about harmonics in transformer..

Q: These transformers normally mounted on power poles or installed inside a large building near…

A: 1) Transformer is an electrical machine which step up step down the voltage without change in…

Q: The diagram for a single phase 60 MVA transformer is given below. Convert it to a Step-down…

A: Design the step down autotransformer Single phase transformer have 60MVA 50/100kV Find the all…

Q: Derive physically the reason of the phase shift in three phase transformer and show the phase shift…

A: The given problem can be laid down into parts. Firstly, the reason of the phase shift in the three…

Q: Using the parameters from the Typical Transformer Values Sheet for a 12.4kV/600V, 100 kVA…

Q: 1. The RMS value of induced emf in the primary N1 winding is E1 =; E2 = 2. In ideal transformer on…

Q: a) An ideal single-phase two-winding transformer with turns ratio a, = N1/N2 is con nected with a…

A: A. The basic relation for a single- phase two winding transformer…

Q: Questions:- 1. What happen when the two transformers are operated in parallel having un equal turn's…

A: According to the bartleby's guidelines we have to solve only one question posted by students so…

Q: If the open circuit voltage is 225V and the full load voltage is 214V, then the percentage…

A: Percentage regulation is given by R R = (VOC - VFL ) / VFL VOC = Open circuit voltage VFL =…

Q: A single-phase l0-kVA, 480/1120 -V transformer is to be used as an auto transformer tying a 600V…

Q: Data from short-circuit and open-circuit tests of a 25-kVA, 6900-230 V, 60 Hz transformer are given…

Q: 3.1 (a) An ideal single-phase two-winding transformer with turns ratio a, = N1/N2 is con- nected…

Q: A generator (480 V, 10 kVA) is connected to an ideal step-up transformer (1:20), and a transmission…

A: Most of human energy requirement is meet by generating electrical energy. Once electrical energy is…

Q: 60 KVA, 415-220 V, 50 Hz transformer I.(exciting current)=2% of the rated current current at 0.75…

Q: Transformer rated powers and relative short-circuit rates in a step-down transformer station are…

A: For the electrical design of the electrical substation, Short circuit MVA and Short circuit current…

Q: why is there preferable use isolating transformers with cascade transformer unit , if the power…

A: Autotransformers are also known as Isolation Transformer. This is due to the fact that their…

Q: 4. Write a conclusion for the experiment, stating the role of core loss.component and magnetizing…

Q: A three-phase Y-Y transformer is rated at 25 MVA, 13.8-kV:69-kV and has a single-phase equivalent…

Q: Hw2.1-3: Derive the following: ing. The shift angle of line voltages for delta/star transformer…

A: In a delta-Star connected transformer, the primary is connected in delta and the secondary is…

Q: PROBLEM A 3300V/440V, single-phase transformer takes a no-load current of 0.8A and the iron loss is…

Q: Q1: What is the influence of transformer connections in single-phase transformers connected for 3-…

A: According to the Bartleby guidelines “Since you have asked multiple question, we will solve the…

Q: For an ideal 2-winding transformer, the armpere-turns of the primary winding, N1/1, is equal to the…

A: For the magnetic circuit, the magneto-motive force is given as:

Q: 3. A 10 kVA, single-phase transformer has a turns ratio of 15:1 and is supplied from a 2,0 kV…

A: Single phase transformer 10KVA , turn ratio 15:1 Primary side voltage 2KV Find the secondary…

Q: Determine the efficiency of three-phase 400 kVA, 11kV/ 380 V transformer at over-loading condition…

Q: Quiz2: We wish to connect a 6 kVA, 120/240 V transformer as an autotransformer to a 120 V source to…

Q: The following test data were obtained from short-circuit and open-circuit tests of a 50-kVA,…

A: Given data Apparent power is S = 50 kVA Voltage is V = 600 V frequency is f = 60 Hz a) Calculating…

Q: A two-winding transformer rated at 100 kVA, is connected as an autotransformer to provide 10kV from…

A: We are authorized to answer one question at a time, since you have not mentioned which question you…

Q: Solve for the efficiency at three-eight load at 0.85 power factor of a 10-kVA single phase…

A: As per our guidelines, we are supposed to answer only one question. Kindly repost the question as a…

Q: As given in the figure, an ideal transformer with a 2: 1 winding ratio is fed from a 240 Volt source…

Q: A 37.5-kVA, 6900-230-V, 60-Hz, single-phase transformer is operating in the step-down mode at rated…

A: a) Given data Apparent power is S = 37.5 KVA Low side voltage is VLS = 230 V Frequency is f = 60 Hz…

Q: Justify if in a Yy transformer (without neutral wire on the supply side) there are homopolar…

A: Here it is mentioned that in a three Yy transformer there are homopolar components of fluxes,…

Q: A three-phase Y-Y transformer is rated at 25 MVA, 13.8-kV:69-kV and has a single-phase equivalent…

Q: a) Discuss two (2) advantages and disadvantages of using three single-phase transformers instead of…

A: NOTE: Since you have asked multiple questions, we will solve the first question for you. If you want…

Q: Consider a current transformer with a turns ratio of 400: 4, a secondary leakage impedance of (0.08…

A: In the given circuit diagram Turn ratio = 400 : 4 secondary leakage impedance is (0.08 + j0.8)…

Q: A single-phase transformer, working at unity power factor has an efficiency of 90 % at both…

Q: A conventional phase transformer given in the figure will be connected as an autotransformer in two…

A: A conventional phase transformer given After convert into auto transformer power rating 1.…

Q: 12.a. Comparing the transformer cores of core-form and shell-form transformers shows that the a.…

A: Solution of question (12.a): Four options are given, we need to choose the correct option. The…

Q: A three-phase Y-Y transformer has specifications of 25 MVA, 15/200 kV and an equivalent series…

A: The solution is given below

Q: A, determine V½ l, Z, and the impedance Z',, which is the value of Z, referred to the primary side…

A: Given: N1=1000N2=250V1=1000∠0°I1=5∠30° The relation between voltage and the turns of the transformer…

Q: A 10 MVA three phase load is to be served by a three phase transformer at a line voltage of 13.8 kV.…

A: Transformer is the static device it is used to transfer the electrical power from one terminal to…

Question

4. An Open-Wye/Open-Delta transformer, as shown in Figure, is formed by two identical
single-phase transformers. The primary line-to-line voltage is 12.47 kV, and the
secondary line-to-line voltage is 208 V. Take <Van = 0 as the angle reference. (Note that
and n are on the secondary side. )
a) Calculate the secondary side line currents, Ia, Ib, and Ic (magnitude and angle).
b) Calculate the primary side line currents IA, IB, and the neutral current IN
(magnitude and angle).
c) Calculate the power factor for the "a-b" and "-c" portion of the transformer.
Indicate whether the power factor is leading or lagging.
12.47kV / 208V
3-phase
Load
Ic
60 kVA
20
kVA
PF=0.9
PF=1
(lag)
IB

Expert Solution

This question has been solved!

Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.

This is a popular solution!

SEE SOLUTION Check out a sample Q&A here

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Trending now

This is a popular solution!

Step by step

Solved in 7 steps with 9 images

SEE SOLUTION Check out a sample Q&A here

Similar questions

An ideal transformer has no real or reactive power loss. (a) True (b) False
A 23/230-kV step-up transformer feeds a three-phase transmission line, which in turn supplies a 150-MVA,0.8 lagging power factor load through a step-down 230/23-kV transformer. The impedance of the line and transformers at 230kVis18+j60. Determine the tap setting for each transformer to maintain the voltage at the load at 23 kV.
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.
(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 ?
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 per-unit equivalent circuits of practical three-phase transformers, under balanced thr-phase operation, in which of the following connect ions would a phase-shifting transformer come up? (a) Y-Y (b) Y- (c) -
Consider the three single-phase two-winding transformers shown in Figure 3.37. The high-voltage windings are connected in Y. (a) For the low-voltage side, connect the windings in , place the polarity marks, and label the terminals a, b, and c in accordance with the American standard. (b) Relabel the terminals a, b, and c such that VAN is 90 out of phase with Va for positive sequence.
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.
For an ideal 2-winding transformer, an impedance Z2 connected across winding 2 (secondary) is referred to winding 1 (primary) by multiplying Z2 by (a) The turns ratio (N1/N2) (b) The square of the turns ratio (N1/N2)2 (c) The cubed turns ratio (N1/N2)3
The ratings of a three-phase three-winding transformer are Primary(1): Y connected 66kV,15MVA Secondary (2): Y connected, 13.2kV,10MVA Tertiary (3): A connected, 2.3kV,5MVA Neglecting winding resistances and exciting current, the per-unit leakage reactances are X12=0.08 on a 15-MVA,66-kV base X13=0.10 on a 15-MVA,66-kV base X23=0.09 on a 10-MVA,13.2-kV base (a) Determine the per-unit reactances X1,X2,X3 of the equivalent circuit on a 15-MVA,66-kV base at the primary terminals. (b) Purely resistive loads of 7.5 MW at 13.2 kV and 5 MW at 2.3kV are connected to the secondary and tertiary sides of the transformer, respectively. Draw the per- unit impedance diagram, showing the per-unit impedances on a 15-MVA,66-kV base at the primary terminals.
A single-phase, 50-kVA,2400/240-V,60-Hz distribution transformer has the following parameters: Resistance of the 2400-V winding: R1=0.75 Resistance of the 240-V winding: R2=0.0075 Leakage reactance of the 2400-V winding: X1=1.0 Leakage reactance of the 240-V winding: X2=0.01 Exciting admittance on the 240-V side =0.003j0.02S (a) Draw the equivalent circuit referred to the high-voltage side of the transformer. (b) Draw the equivalent circuit referred to the low-voltage side of the transformer. Show the numerical values of impedances on the equivalent circuits.
ََQ/ 400/200 V, single-phase transformer is supplying a load of 50A at a power factor of 0.866 lagging. The no-load current is 2A at 0.208 p.f. lagging. .. Find The primary current is ...... A * The primary power factor is ........ lagging *