Figure 2 shows the circuit of a simple power system. The ratings of the generators,transformers and the motors are as shown in the figure. The reactance of lines 1 and 2are 40 ohms and 50 ohms respectively. Assume that system is unloaded, and the generatorsare generating their rated voltage. Select the generator G₁ ratings as base values.Choose the fault location in bus 1 And give the below answersFor a symmetrical three phase fault on the bus(a).Determine the Thevenin's equivalent circuit which can be used to calculate the fault current.(b) Calculate the fault current contribution from the generator connected to the bus on which you have selected for fault calculation Figure 2 shows the circuit of a simple power system. The ratings of the generators,transformers and the motors are as shown in the figure. The reactance of lines 1 and 2are 40 Q and 50 2 respectively. Assume that system is unloaded, and the generatorsare generating their rated voltage. Select the generator G, ratings as base values.Choose the fault location200 MVA150 MVAG220kVBus- 213.8 kVG1X=17%200 MVAX = 20%250 MVA240Υ / 20Δ kV'T2T1 m 13.8A/240Y kVX =10%Bus- 3X=11%Bus - 1j 40 2Linel50 NLine250 MVAm T,120 MVAT3240 A/11Y kV240 Y /18A kVX = 10%X =10%120 MVA50 MVAG3M18KV11kVX =19%X= 20%Figure 2For a symmetrical three phase fault on the bus(i)Draw the reactance diagram for the fault with all the reactances marked inper unit.(ii)Determine the Thevenin's equivalent circuit which can be used to calculatethe fault current.(ii)Calculate the fault current in ampere and fault power in MVA.(iv)Calculate the fault current contribution from the generator connected to thebus on which you have selected for fault calculation.

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Figure 2 shows the circuit of a simple power system. The ratings of the generators, transformers and the motors are as shown in the figure. The reactance of lines 1 and 2 are 40 ohms and 50 ohms respectively. Assume that system is unloaded, and the generators are generating their rated voltage. Select the generator G₁ ratings as base values. Choose the fault location in bus 1 And give the below answers For a symmetrical three phase fault on the bus (a).Determine the Thevenin's equivalent circuit which can be used to calculate the fault current. (b) Calculate the fault current contribution from the generator connected to the bus on which you have selected for fault calculation

Figure 2 shows the circuit of a simple power system. The ratings of the generators, transformers and the motors are as shown in the figure. The reactance of lines 1 and 2 are 40 ohms and 50 ohms respectively. Assume that system is unloaded, and the generators are generating their rated voltage. Select the generator G₁ ratings as base values. Choose the fault location in bus 1 And give the below answers For a symmetrical three phase fault on the bus (a).Determine the Thevenin's equivalent circuit which can be used to calculate the fault current. (b) Calculate the fault current contribution from the generator connected to the bus on which you have selected for fault calculation

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 3.56P: Three single-phase two-winding transformers, each rated 3kVA,220/110volts,60Hz, with a 0.10 per-unit...

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