Draw the reactance diagram, with all reactance's marked in per-unit. Select the 100 MVA and 25kV as base values. The ratings of the components are: G: 40MVA, 25KV, X" = 20% 3 phase transformer T1= 20 MVA, 220/25 kV, X=15% 3 phase transformer T2= 30 MVA, 220/11 kV, X=15% Motor: 50 MVA, 11 kV, X"=20% 30 km Transmission line: Series reactance X=j 60 2 30 km T1 T2 計 Line to M A

Draw the reactance diagram, with all reactance's marked in per-unit. Select the 100 MVA and 25kV as base values. The ratings of the components are: G: 40MVA, 25KV, X" = 20% 3 phase transformer T1= 20 MVA, 220/25 kV, X=15% 3 phase transformer T2= 30 MVA, 220/11 kV, X=15% Motor: 50 MVA, 11 kV, X"=20% 30 km Transmission line: Series reactance X=j 60 2 30 km T1 T2 計 Line to M A

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter4: Symbols

Section: Chapter Questions

Problem 7SQ: The symbol shown is a(n) a. iron core transformer. b. auto transformer. c. current transformer. d....

See similar textbooks

Similar questions

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.
The symbol shown is a(n) a. iron core transformer. b. auto transformer. c. current transformer. d. air core transformer.
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.
With the American Standard notation, in either a Y-or-Y transformer, positive- sequen quantities on the high-voltage side shall lead their corresponding quantities on the low-voltage side by 30. (a) True (b) False
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
Using the transformer ratings as base quantities. work Problem 3.14 in per-unit.
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.
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.
Three single-phase two-winding transformers, each rated 3kVA,220/110volts,60Hz, with a 0.10 per-unit leakage reactance, are connected as a three-phase extended autotransformer bank, as shown in Figure 3.36(c). The low-voltage winding has a 110 volt rating. (a) Draw the positive-sequence phasor diagram and show that the high-voltage winding has a 479.5 volt rating. (b) A three-phase load connected to the low-voltage terminals absorbs 6 kW at 110 volts and at 0.8 power factor lagging. Draw the per-unit impedance diagram and calculate the voltage and current at the high-voltage terminals. Assume positive-sequence operation.
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) -
Seconday winding of transformer is made-up of material. O insulated CRGO conductor O insulated copper conductor O Cold Rolled Grain Oriented (CRGO) conductor Cold Rolled Grain Oriented (CRGO) Silicon Steel
In the single-phase, three- winding, transformer, the primary current is equal to lo at the condition of ints there is no load on tertiary windings the current in secondary windings equal to zero the resistances (R1, R2, and R3) in transformer windings are equal the inductances (L1, L2, and L3) in transformer windings are equal.