For the following single line diagram of a three-phase system, a three-phase fault occurs at point P and just before the fault the line voltage is 18 kV at P. Find out the transient fault current in pu and original value at point P. Take, the given kVA and kV of the G1 as the new base. [hint: the transient and sub-transient reactances of the synchronous generators are assumed to be same. But for the motors, assume that the transient one is 1.7 times of the sub-transient reactance.] 20,000 KV A 6.9KV yo00 KVA 5KV '14% G1 Tz 平 33/69 AV 11/33KV 20000 KVA 10% G2 lond 5+j8 2 15070 KVA 12%. 25,000 KVA 6.9KV [AN the mpedarmces are given per- unit values) as orebtraen sien

For the following single line diagram of a three-phase system, a three-phase fault occurs at point P and just before the fault the line voltage is 18 kV at P. Find out the transient fault current in pu and original value at point P. Take, the given kVA and kV of the G1 as the new base. [hint: the transient and sub-transient reactances of the synchronous generators are assumed to be same. But for the motors, assume that the transient one is 1.7 times of the sub-transient reactance.] 20,000 KV A 6.9KV yo00 KVA 5KV '14% G1 Tz 平 33/69 AV 11/33KV 20000 KVA 10% G2 lond 5+j8 2 15070 KVA 12%. 25,000 KVA 6.9KV [AN the mpedarmces are given per- unit values) as orebtraen sien

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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