UHEngineer
Electrical
Since I'm completely new to PSS/E I have a following question about the output of this file.
I am analyzing a smaller network that is connected to a larger network through a transformer.
A short circuit analysis is made on the bus of the larger network (meaning, I need the equivalent impedance of it to calculate short circuits in the smaller network). Consider the following output from PSS/E:
SS®E ASCC SHORT CIRCUIT CURRENTS THU, MAY 19 2011 14:52
X---------- BUS ----------X
MVA AMP DEG
3PH 2912.16 7310.2 -54.88
LG 3005.43 7544.3 -54.45
THEVENIN IMPEDANCE, X/R (OHM) Z+:/18.457/82.188, 7.28914 Z-:/18.258/82.622, 7.72320 Z0:/16.944/80.360, 5.88722
How do I read the thevenin impedances, because it seems that either R is too large, or I am reading it completely wrong. For example, is the positive sequence X+=18.457 and positive sequence Z+=7.28 ?
The "correct" impedances will be then have to be trasformed to a lower voltage level. But what are the correct values?
Thanks in advance!
(And no, this is not an april joke!)
I am analyzing a smaller network that is connected to a larger network through a transformer.
A short circuit analysis is made on the bus of the larger network (meaning, I need the equivalent impedance of it to calculate short circuits in the smaller network). Consider the following output from PSS/E:
SS®E ASCC SHORT CIRCUIT CURRENTS THU, MAY 19 2011 14:52
X---------- BUS ----------X
MVA AMP DEG
3PH 2912.16 7310.2 -54.88
LG 3005.43 7544.3 -54.45
THEVENIN IMPEDANCE, X/R (OHM) Z+:/18.457/82.188, 7.28914 Z-:/18.258/82.622, 7.72320 Z0:/16.944/80.360, 5.88722
How do I read the thevenin impedances, because it seems that either R is too large, or I am reading it completely wrong. For example, is the positive sequence X+=18.457 and positive sequence Z+=7.28 ?
The "correct" impedances will be then have to be trasformed to a lower voltage level. But what are the correct values?
Thanks in advance!
(And no, this is not an april joke!)