2:40 PM O sen Chapter-6-Cons... Assignment_1 ☑ ① Chapter-7-Sym-·· | 41 1. The system shown in Figure belowis initially on no load with generators oper- ating at their rated voltage with their emfs in phase. The rating of the genera- tors and the transformers and their respective percent reactances are marked on the diagram. All resistances are neglected. The line impedance is j160 . A three-phase balanced fault occurs at the receiving end of the transmission line. Determine the short-circuit current and the short-circuit MVA. 60 MVA, 30 kV X₁₂ = 24% о Xt = 16% збо XL = 160 Ω 口 03 80to 40 MVA, 30 kV X₁₂ = 24% Xa 100 MVA 30/400 kV M₁ =0H M=0. 18 20 in exon +=0:16 آفاق واسعة

2:40 PM O sen Chapter-6-Cons... Assignment_1 ☑ ① Chapter-7-Sym-·· | 41 1. The system shown in Figure belowis initially on no load with generators oper- ating at their rated voltage with their emfs in phase. The rating of the genera- tors and the transformers and their respective percent reactances are marked on the diagram. All resistances are neglected. The line impedance is j160 . A three-phase balanced fault occurs at the receiving end of the transmission line. Determine the short-circuit current and the short-circuit MVA. 60 MVA, 30 kV X₁₂ = 24% о Xt = 16% збо XL = 160 Ω 口 03 80to 40 MVA, 30 kV X₁₂ = 24% Xa 100 MVA 30/400 kV M₁ =0H M=0. 18 20 in exon +=0:16 آفاق واسعة

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 3.15MCQ: To convert a per-unit impedance from old to new base values, the equation to be used is...

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The one-line diagram of a simple power system is shown in Figure below. The neutral of each generator is grounded through a current-limiting reactor of 0.25/3 per unit on a 100-MVA base. The system data expressed in per unit on a common 100-MVA base is tabulated below. The generators are running on no-load at their rated voltage and rated frequency with their emfs in phase. G Stark Item Base MVA Voltage Rating X' x² 20 kV 20 kV 20/220 kV 20/220 kV 100 0.05 0.15 0.15 0.10 0.10 220 kV 0.125 0.125 0.30 0.15 0.25 025 0.7125 0.15 100 100 0.15 0.05 0.10 0.10 0.10 100 0.10 100 100 Lu La 220 kV 0.15 220 kV 0.35 100 A balanced three-phase fault at bus 3 through a fault impedance Zf= jo.I per unit. The magnitude of the fault current in amperes in phase b for this fault is: Select one: A. 345.3 B. 820.1 C. 312500 3888888 产产

Power system protection
The reactance of a generator is given as 0.25 per-unit based on the generator’s of 18 kV, 500 MVA. Find its per-unit reactance on a base of 20 kV, 100 MVA. a. 0.0505 b. 0.0605 c. 0.0405 d. 0.0606
Three single-phase transformers, each rated 10 MVA , 66.4/12.5 kV, 60 Hz , with an equivalent series reactance of 0.1 per unit divided equally between primary and secondary, are connected in a three-phase bank. The high-voltage windings are Y-connected and their terminals are directly connected to a 115-kV three-phase bus. The secondary terminals are all shorted together. Find the currents entering the high-voltage terminals and leaving the low-voltage terminals if the low-voltage windings are (a) Y-connected and (b) Δ- connected.
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) -
Three single-phase, two-winding transformers, each rated 450MVA,20kV/288.7kV, with leakage reactance Xeq=0.10perunit, are connected to form a three-phase bank. The high-voltage windings are connected in Y with a solidly grounded neutral. Draw the per-unit equivalent circuit if the low-voltage windings are connected (a) in with American standard phase shift or (b) in Y with an open neutral. Use the transformer ratings as base quantities. Winding resistances and exciting current are neglected.
Three single-phase two-winding transformers, each rated 25MVA,54.2/5.42kV, are connected to form a three-phase Y- bank with a balanced Y-connected resistive load of 0.6 per phase on the low-voltage side. By choosing a base of 75 MVA (three phase) and 94 kV (line-to-line) for the high-voltage side of the transformer bank, specify the base quantities for the low-voltage side. Determine the per-unit resistance of the load on the base for the low-voltage side. Then determine the load resistance RL in ohms referred to the high-voltage side and the per-unit value of this load resistance on the chosen base.
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.
Please, I do not want a theoretical solution or using artificial intelligence. I want a solution on paper using the mathematical laws of the topic
In power distribution systems, what is sometimes necessary to install to reduce harmonic frequencies and distortion between the three-phase transformers and distribution panels?
Three zones of a single-phase circuit are identified in Figure. The zones are connected bytransformers T1 and T2, whose ratings are also shown.Using base values of 30 kVA and 240 volts in zone 1:a. draw the per-unit circuit and determine the per-unit impedances and the per-unitsource voltage.b. calculate the load current both in per-unit and in amperes. Transformer windingresistances and shunt admittance branches are neglected.
2A. What is another term for "shunt"? a) in series b) in parallel c) compounded d) none of the above 2B. Which of the following is/are a basic type of DC generator connection? a) series b) shunt c) compound d) all of the above