ABB REG316 4 Series - Page 198

ABB Switzerland Ltd REG 316*4 1MRB520049-Uen / Rev. F
3-160
Example
Turboalternator 100 MVA; 12 kV; 4.8 kA
x
d
= 2.0; x
d
' = 0.25
V.t's
K
U
U
u
N
N2
== =
1
3
3
12000
100
120
C.t's
K
i
==
5000
1
5000
Xx
U
I
K
K
Ad
GN
GN
i
u
=´ ´ =
×
´=
3
320
12000
34800
5000
120
32083..
W
X
x
U
I
K
K
B
dGN
GN
i
u
=´ ´ = ´
×
´=
'
.
.
2
3
3
025
2
12000
34800
5000
120
31302W
The reactance settings referred to the protection ratings U
N
and
I
N
become:
XA - Setting ==-´=-
X
U
I
A
N
N
208 3
100
1208
.
.
XB - Setting ==-´=-=
X
U
I
B
N
N
13 02
100
10130013
.
..