Page 846 - Industrial Power Engineering and Applications Handbook

24/800 Industrial Power Engineering and Applications Handbook -,- 6
9
11/400 kV 4: 30 MVA,

P
400/132 kV Jk---j 1
R= 1.95 Q
I
Primary
lil transmission
T

132/33 - -ev. capacitors --_ B
Shunt 4
-1
Secondary
transmission
I
I
I
I
B kV A HV - +
LT loads = 29.4 MW at 0.88 p.f.
I
I
I I
Section (b) Details of section B-B
B-8 under J j PrirJlary
consideration I distribution
I 1 B O @ O @ O
- @ Resistance of overhead lines of section B-B.
33/0.4 kV @ Leakage reactance of transmitter-end transformer.
Xc
@ Inductive reactance of overhead lines of section B-B
@) Capacitive reactance of series capacitors.
Secondary
distribution
29.4 MW Leakage reactance of receiving-end transformer.
(a) Typical primary distribution network (c) Equivalent circuit of Section B-B
Figure 24.25 Determining the value of series capacitors for a primary distribution network

To study the impact of series compensation we consider 16.62
the full-rated current of the transformer and the line for = 22.43 tan 2 1.43
optimum utilization of the entire system.
= 22.43 L 17.16" (Figure 24.26)
- -
33
+
E, = - I, . Z, in kV :. Voltage drop = 22.43 - 19.05
J3
= 3.38 kV
= 19.05 + __
(1000 or 15.07 % of E,
= 19.05 + 0.525 x 1.95 L - 11.48" + 0.525
3 6 . 9 6 k V
X 13.26 L (90 - 11.48')
= 19.0s + 1.024[cos (-11.48') + J sin (-1 1.48')]
+ 6.96 (cos 78.52" + J sin 78.52')
17.16"
= 19.05 + 1.024(0.98 - J 0.199) + 6.96(0.199 + J 0.98)
V, = 19.05 kV 1.00 kv
= 19.05 + 1.00 - J 0.20 + 1.38 + J 6.82 525 A
= 2 I .43 + J 6.62 Figure 24.26 Receiving-end voltage after shunt compensation