A 300-MV A 20-kV three-phase generator has a subtransient reactance of 21%. The generator supplies a number of synchronous motors over a 64-km transmission line having transformers at both ends, as shown on the one-line diagram of the following figure. The motors, all rated 13.2 kV, are represented by just two equivalent motors. The neutral of one motor M, is grounded through reactance. The neutral of the second motor M2 is not connected to ground (an unusual condition). Rated inputs to the motors are 200 MVA and 100 MVA for M1 and M2, respectively. For both motors reactance XM = 20.6%. The three-phase transformer T, is rated 350 MVA, 230/20 kV with leakage reactance of 14%. Transformer T, is rated 220/13.2 kV, 300 MVA with leakage reactance of 10%. The series reactance of the transmission line is 0.44 Ohm/km. Draw the reactance diagram with all reactances marked in per unit. Select the generator rating as the base in the generator circuit.

A 300-MV A 20-kV three-phase generator has a subtransient reactance of 21%. The generator supplies a number of synchronous motors over a 64-km transmission line having transformers at both ends, as shown on the one-line diagram of the following figure. The motors, all rated 13.2 kV, are represented by just two equivalent motors. The neutral of one motor M, is grounded through reactance. The neutral of the second motor M2 is not connected to ground (an unusual condition). Rated inputs to the motors are 200 MVA and 100 MVA for M1 and M2, respectively. For both motors reactance XM = 20.6%. The three-phase transformer T, is rated 350 MVA, 230/20 kV with leakage reactance of 14%. Transformer T, is rated 220/13.2 kV, 300 MVA with leakage reactance of 10%. The series reactance of the transmission line is 0.44 Ohm/km. Draw the reactance diagram with all reactances marked in per unit. Select the generator rating as the base in the generator circuit.

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 3.44P: A 130-MVA,13.2-kV three-phase generator, which has a positive-sequence reactance of 1.5 per unit on...

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