336 CHAPTER 9
POWER-FLOW SOLUTIONS
similar equation of bus
@
, we would obtain six equations in the six state
variables 02 to 04 and I V21 to I V41. However we solve for the complex voltages
directly from the equations as they appear. The solution proceeds by iteration
based on the scheduled real and reactive power at buses 0, ®, and
@
, the
scheduled slack bus voltage
V
I =
I V
I
I&, and initial voltage estimates viO),
VJO), and V4(
0
) at the other buses.
Solution of Eq. (
9
.15) gives the corrected voltage VP) calculated from
V
el)
=
_1
_
[P2.Kh
-
j
Q2
,seh.
_ (Y
V
Y
V
(O)
Y V
(O»)]
2
y V
(0
)*
2
1 1 + 2J J
+
2 4
2
2
2
(9.17
)
in which all quantities in the right-hand-side expression are either fixed speci