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a
d
u
e
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ail
y
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o
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ta
g
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t
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at
cr
ea
tes
a
m
aj
o
r
ec
o
n
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m
ic
c
h
alle
n
g
e
[
6
]
.
A
n
u
m
b
er
o
f
in
d
u
s
tr
ies
i
n
Nig
er
ia
clo
s
ed
d
o
w
n
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a
r
esu
lt
o
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in
ad
eq
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ate
p
o
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u
p
p
l
y
w
h
ich
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as
m
ad
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b
u
s
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n
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atio
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r
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n
es
s
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d
m
a
n
u
f
ac
t
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er
s
[
7
,
8
]
.
A
lt
h
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g
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,
th
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i
s
a
h
i
g
h
f
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ite
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an
d
th
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s
,
th
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f
o
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e,
i
m
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lies
t
h
at
th
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Ni
g
er
ia
Natio
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a
l
Gr
id
is
n
o
t
r
o
b
u
s
t
a
n
d
th
er
ef
o
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s
ce
p
tib
le
to
v
o
lta
g
e
i
n
s
tab
ilit
y
a
n
d
co
llap
s
e
[
7
]
.
C
o
m
p
ar
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g
th
e
f
r
eq
u
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n
c
y
o
f
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cc
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1
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[
9
]
.
T
h
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u
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b
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d
li
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g
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f
p
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y
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also
p
lace
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itat
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o
n
it
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e
x
p
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n
,
th
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e
s
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l
ts
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h
e
o
p
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f
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an
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m
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clo
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to
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r
li
m
its
lead
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n
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to
m
o
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p
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u
tag
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n
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s
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llap
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es
[
1
0
,
11]
Fig
u
r
e
1
.
C
o
m
p
ar
in
g
v
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o
llap
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as a
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cc
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th
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NN
G
[
9
]
I
n
t
h
is
s
t
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y
,
th
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p
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ith
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[
1
2
]
,
th
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p
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p
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Ne
w
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b
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I
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2
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s
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3
3
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k
V
Nig
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(
NNG)
.
Du
r
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p
er
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.
2.
VO
L
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A
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S
T
AB
I
L
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T
Y
I
N
DICE
S
A
n
u
m
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lab
le
f
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m
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n
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g
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et
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er
a
s
y
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te
m
v
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is
s
tab
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an
d
i
f
n
o
t
s
tab
le
t
h
e
ex
te
n
t
to
w
h
ic
h
th
e
s
y
s
te
m
is
to
in
s
tab
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y
.
T
h
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in
d
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r
ev
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l
th
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cr
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b
u
s
o
f
a
P
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an
d
also
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s
tab
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s
tat
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th
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p
o
w
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lin
e
s
co
n
n
ec
t
ed
in
b
et
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ee
n
t
w
o
b
u
s
es i
n
an
i
n
ter
co
n
n
ec
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P
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1
3
,
1
4
]
.
T
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P
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R
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P
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Q
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I
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p
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d
to
in
j
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t o
r
ab
s
o
r
b
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p
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[
1
5
-
1
7
]
.
T
h
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e
n
v
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to
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s
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ce
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[
1
8
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1
9
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.
Fo
r
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y
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v
al
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en
th
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s
y
s
t
e
m
i
s
u
n
s
tab
le
[
1
9
,
2
0
]
.
I
f
th
e
e
ig
e
n
v
alu
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is
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(
0
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,
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v
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in
s
tab
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u
r
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[
2
1
]
.
Usi
n
g
t
h
e
m
o
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n
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s
is
,
t
h
e
QV,
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e
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an
d
th
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b
ased
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s
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y
[
2
2
,
2
3
]
is
q
u
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n
ten
s
i
v
e
to
co
m
p
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e,
it
is
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p
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em
a
n
d
s
6
a
f
as
t
r
esp
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s
e.
I
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p
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to
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3.
CO
M
M
O
N
L
I
NE
VO
L
T
A
G
E
ST
AB
I
L
I
T
Y
I
NDI
CATO
RS
T
h
e
f
o
llo
w
in
g
h
i
g
h
lig
h
t
s
t
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4
m
aj
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tab
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in
d
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th
a
t
h
av
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b
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n
a
p
p
lied
b
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p
r
ev
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u
s
s
t
u
d
ies
:
3
.
1
.
L
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s
t
a
bil
it
y
ind
ex
(
L
m
n)
T
h
e
id
ea
o
f
t
h
e
L
m
n
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s
d
er
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ed
f
r
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m
th
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g
le
l
in
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p
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tr
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s
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s
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p
t.
I
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s
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elo
p
ed
f
o
r
ev
al
u
ati
n
g
th
e
s
tab
ili
t
y
o
f
a
p
o
w
er
li
n
e
co
n
n
ec
ti
n
g
t
w
o
b
u
s
e
s
i
n
an
in
ter
co
n
n
ec
ted
s
y
s
t
e
m
w
h
ic
h
h
as
b
ee
n
s
ca
led
d
o
w
n
to
a
s
i
n
g
le
lin
e
P
SN.
L
m
n
is
e
x
p
r
ess
ed
as f
o
llo
w
s
:
(
1
)
Fo
r
in
ter
p
r
etatio
n
p
u
r
p
o
s
es,
i
f
th
e
L
m
n
i
n
d
ex
is
clo
s
e
to
1
,
t
h
e
li
n
e
in
th
e
P
SN
i
s
d
ee
m
ed
clo
s
e
to
in
s
tab
il
it
y
b
u
t th
e
s
y
s
te
m
i
s
s
aid
to
b
e
s
ta
b
le
w
h
en
t
h
e
L
m
n
v
alu
e
i
s
les
s
th
a
n
1
[
2
4
]
.
3
.
2
.
F
a
s
t
v
o
lt
a
g
e
s
t
a
bil
it
y
ind
ex
(
F
VSI
)
T
h
e
u
s
e
o
f
th
e
FV
SI
w
a
s
p
r
o
p
o
s
ed
in
th
e
s
tu
d
y
b
y
[
2
5
]
.
T
h
e
FVSI
lik
e
th
e
L
m
n
als
o
ap
p
lies
th
e
co
n
ce
p
t o
f
p
o
w
er
f
lo
w
t
h
r
o
u
g
h
a
s
in
g
le
lin
e
[
1
1
]
.
T
h
e
FVSI
w
as d
e
v
elo
p
ed
u
s
i
n
g
t
h
e
s
tan
d
ar
d
li
n
e
cu
r
r
e
n
t
eq
u
atio
n
f
o
r
a
lin
e
co
n
n
ec
ted
b
et
w
ee
n
t
w
o
b
u
s
e
s
.
I
t is
m
at
h
e
m
atica
ll
y
d
ef
i
n
ed
as
f
o
l
lo
w
s
:
(
2
)
T
h
e
m
o
s
t
cr
itical
li
n
e
in
a
b
u
s
is
th
e
lin
e
t
h
at
h
as
a
s
tab
ilit
y
in
d
ex
v
a
lu
e
t
h
at
is
clo
s
est
to
o
n
e
(
1
)
an
d
s
u
c
h
a
b
u
s
h
as
t
h
e
ten
d
en
c
y
t
o
tr
ig
g
er
s
y
s
te
m
in
s
tab
ilit
y
[
2
6
]
.
I
n
d
er
iv
in
g
t
h
e
in
d
ex
,
a
n
ass
u
m
p
tio
n
is
m
ad
e
th
at
t
h
e
d
if
f
er
en
ce
b
et
w
ee
n
th
e
v
o
ltag
e
a
n
g
le
s
o
f
t
h
e
t
w
o
lo
ad
b
u
s
es is
q
u
i
te
s
m
all.
3
.
3
.
L
ine
s
t
a
bil
it
y
f
a
ct
o
r
(
L
Q
P
)
T
h
e
L
QP
w
a
s
d
ev
e
lo
p
ed
b
y
[
2
7
]
,
b
y
ap
p
l
y
i
n
g
a
m
e
th
o
d
f
o
r
f
ix
in
g
th
e
d
is
cr
i
m
i
n
an
t
o
f
th
e
p
o
w
er
q
u
ad
r
atic
eq
u
atio
n
at
a
v
al
u
e
t
h
at
is
≥
0
.
T
h
e
L
QP
in
d
ex
is
d
ef
i
n
ed
a
s:
(
3
)
T
h
e
v
alu
e
o
f
th
e
L
QP
in
d
ex
f
o
r
a
s
tab
le
s
y
s
te
m
m
u
s
t
b
e
k
ep
t
b
elo
w
1
o
th
er
wis
e
it
m
a
y
tr
ig
g
er
a
v
o
ltag
e
co
llap
s
e.
3
.
4
.
L
ine
v
o
lt
a
g
e
s
t
a
bil
it
y
ind
ex
(
L
VS
I
)
T
h
e
L
VSI
is
b
ased
o
n
th
e
r
elatio
n
s
h
ip
ex
is
tin
g
b
et
w
ee
n
th
e
b
u
s
v
o
lta
g
e
an
d
t
h
e
lin
e
‟
s
r
ea
l
p
o
w
er
[
1
4
]
.
I
n
th
is
m
o
d
el,
a
f
ailu
r
e
en
s
u
e
s
w
h
e
n
th
e
l
in
e
r
e
s
is
ta
n
ce
o
f
t
h
e
p
o
w
er
lin
e
r
ed
u
ce
s
to
a
n
ea
r
ze
r
o
v
alu
e.
T
h
e
L
VSI
is
d
ef
in
ed
i
n
(
4
)
.
2
2
4
1
s
in
r
mn
s
XQ
L
V
2
4
1
r
s
ZQ
F
V
S
I
VX
22
4
sr
ss
XX
L
Q
P
p
Q
VV
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2088
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
9
,
No
.
6
,
Dec
em
b
er
2
0
1
9
:
5
1
2
5
-
5
1
3
3
5128
(
4
)
T
h
e
L
in
e
Vo
lta
g
e
Stab
ilit
y
I
n
d
ex
is
ex
tr
a
s
e
n
s
iti
v
e
to
,
an
d
th
is
is
b
ec
a
u
s
e
co
s
(
θ
-
)
i
s
f
aster
t
h
a
n
s
in
(
θ
-
)
i
n
t
h
e
9
0
r
eg
io
n
a
n
d
th
is
cr
ea
te
s
a
te
n
d
en
c
y
f
o
r
id
en
ti
f
y
i
n
g
a
h
ea
lt
h
y
l
in
e
a
s
a
cr
itical
lin
e
[
2
8
]
.
No
te
th
at
in
t
h
e
e
x
p
r
ess
io
n
i
n
(
4
)
,
all
th
e
s
y
m
b
o
ls
d
o
n
o
t h
a
v
e
th
eir
u
s
u
al
m
ea
n
in
g
s
.
4.
NE
W
L
I
N
E
S
T
AB
I
L
I
T
Y
I
N
DE
X_
1
(
NL
SI
-
1)
T
o
d
er
iv
e
th
e
N
L
SI
-
1
th
e
p
o
wer
s
y
s
te
m
m
o
d
el
o
f
a
t
w
o
-
b
u
s
n
et
w
o
r
k
u
s
i
n
g
t
h
e
s
i
n
g
le
li
n
e
d
iag
r
a
m
a
s
s
h
o
w
n
in
F
ig
u
r
e
2
is
co
n
s
id
er
e
d
.
A
ll th
e
v
ar
iab
les a
n
d
p
ar
am
eter
s
ar
e
g
iv
e
n
i
n
p
er
u
n
it.
Fig
u
r
e
2
.
T
h
e
s
in
g
le
li
n
e
m
o
d
e
l o
f
a
2
-
b
u
s
p
o
w
er
s
y
s
te
m
As
s
h
o
w
n
i
n
Fi
g
u
r
e
1
,
b
u
s
„
s
‟
(
th
e
r
ef
er
e
n
ce
b
u
s
)
a
n
d
b
u
s
„
r
‟
ar
e
t
h
e
s
e
n
d
in
g
e
n
d
a
n
d
t
h
e
r
ec
eiv
in
g
-
en
d
b
u
s
r
esp
ec
tiv
e
l
y
.
T
h
e
m
o
d
el
v
ar
iab
les
ar
e
ex
p
lai
n
ed
as
f
o
llo
w
s
:
V
r
a
n
d
V
s
ar
e
th
e
r
ec
eiv
i
n
g
en
d
a
n
d
th
e
s
e
n
d
in
g
e
n
d
b
u
s
v
o
lta
g
e,
P
r
an
d
S
r
ar
e
th
e
r
ea
l
p
o
w
er
a
n
d
th
e
r
ea
ct
iv
e
p
o
w
er
r
esp
ec
tiv
el
y
at
th
e
r
ec
ei
v
i
n
g
-
en
d
b
u
s
„
r
‟
;
r
an
d
s
ar
e
t
h
e
v
o
ltag
e
an
g
les
o
f
t
h
e
r
ec
eiv
i
n
g
-
en
d
an
d
s
e
n
d
in
g
-
en
d
b
u
s
es
r
es
p
ec
tiv
el
y
;
s
ta
n
d
s
f
o
r
th
e
d
if
f
er
en
ce
b
et
w
ee
n
r
an
d
s.
A
cc
o
r
d
in
g
to
th
e
s
tu
d
y
b
y
[
1
2
]
,
w
id
e
an
g
u
lar
d
i
f
f
er
e
n
ce
s
m
a
y
p
o
r
t
en
d
a
h
ig
h
er
r
is
k
o
f
a
s
y
s
te
m
co
llap
s
e.
T
h
is
,
th
er
e
f
o
r
e,
n
ec
ess
itate
s
th
e
u
s
e
o
f
t
h
e
NL
SI_
1
w
h
ich
i
n
co
r
p
o
r
ates
a
s
w
itc
h
i
n
g
f
u
n
ctio
n
,
σ
,
an
d
lo
g
ic
f
o
r
co
m
p
u
ti
n
g
th
e
p
r
o
x
i
m
it
y
o
f
v
o
lta
g
e
co
llap
s
e
in
o
r
d
er
to
en
h
an
ce
t
h
e
p
r
ec
is
io
n
o
f
s
tab
ili
t
y
ass
es
s
m
en
t.
T
h
e
N
L
SI_
1
is
d
ef
i
n
ed
as:
(
5
)
I
n
(
5
)
,
σ
is
th
e
s
w
i
tch
i
n
g
f
u
n
ct
io
n
w
h
i
le
is
a
m
o
d
if
ier
.
T
h
e
v
alu
e
o
f
σ
d
ep
en
d
s
o
n
t
h
e
m
a
g
n
i
tu
d
e
o
f
th
e
a
n
g
u
lar
d
i
f
f
er
en
ce
δ.
Fro
m
t
h
e
lo
ad
-
f
lo
w
p
r
o
g
r
a
m
,
t
h
e
v
al
u
e
o
f
δ
i
s
co
m
p
u
ted
a
n
d
v
er
if
ied
a
g
ai
n
s
t
a
b
aselin
e
v
al
u
e,
s
o
as
to
d
ete
r
m
in
e
i
f
σ
is
1
o
r
0
.
T
h
e
s
y
s
te
m
v
o
lta
g
e
w
ill
b
e
s
tab
le
i
f
N
L
SI
-
1
is
b
elo
w
1
.
T
h
e
clo
s
er
th
e
v
alu
e
o
f
N
L
SI
-
1
g
ets to
1
th
e
h
i
g
h
er
th
e
r
is
k
o
f
a
v
o
ltag
e
co
llap
s
e.
T
h
is
i
n
d
ex
h
elp
s
i
n
e
n
s
u
r
in
g
o
p
tim
a
l
allo
ca
tio
n
o
f
co
m
p
e
n
s
atio
n
d
ev
ice
s
to
w
ar
d
s
m
iti
g
ati
n
g
v
o
ltag
e
co
llap
s
e
b
y
h
elp
in
g
to
id
en
t
if
y
th
e
m
o
s
t v
u
l
n
er
ab
le
an
d
w
ea
k
est lin
e
b
u
s
[
9
,
2
9
]
.
5.
T
H
E
NI
G
E
RI
A
NAT
I
O
NA
L
G
R
I
D
2
8
-
B
US,
3
3
0
-
K
V
NE
T
WO
RK
T
h
e
d
iag
r
am
i
n
Fi
g
u
r
e
3
s
h
o
w
s
t
h
e
NNG,
2
8
-
B
u
s
,
3
3
0
-
k
V
Net
w
o
r
k
w
h
ic
h
h
a
s
n
i
n
e
(
9
)
g
en
er
ato
r
(
P
V)
b
u
s
es,
n
i
n
etee
n
(
1
9
)
L
o
ad
(
P
Q)
b
u
s
es
an
d
th
ir
t
y
-
o
n
e
(
3
1
)
in
ter
co
n
n
ec
ted
b
r
an
ch
e
s
.
I
n
m
o
s
t
p
ar
ts
o
f
th
e
n
et
w
o
r
k
,
th
e
NNG
is
c
h
a
r
ac
ter
ized
b
y
lo
w
v
o
ltag
e
s
as
a
r
esu
lt
o
f
th
e
i
n
s
u
f
f
ic
ien
t
d
i
s
p
atch
an
d
co
n
tr
o
l
in
f
r
astru
ct
u
r
es
[
3
0
]
.
T
h
e
NNG
is
a
r
ad
ial
g
r
id
;
it
i
s
w
ea
k
a
n
d
o
v
er
lo
ad
ed
w
h
ic
h
c
u
l
m
i
n
ates
in
h
ig
h
tr
an
s
m
is
s
io
n
lo
s
s
es
a
n
d
in
ce
s
s
an
t
n
et
w
o
r
k
co
llap
s
e
[
3
1
]
.
A
s
a
r
esu
lt
o
f
t
h
ese
f
ac
to
r
s
,
th
e
NNG
is
w
ea
k
a
n
d
h
ig
h
l
y
s
tr
e
s
s
ed
w
h
ich
m
a
k
es it
v
u
l
n
er
ab
le
to
v
o
ltag
e
i
n
s
tab
ili
t
y
an
d
t
h
e
ev
e
n
t
u
al
s
y
s
te
m
co
l
lap
s
e
[
7
,
3
2
]
.
4
1
c
o
s
r
s
RP
L
V
S
I
V
2
2
2
1
4
_
1
1
1
0
s
in
c
r
c
s
Z
Q
X
N
L
S
I
X
V
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J
E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2
0
8
8
-
8708
P
o
w
er sys
te
m
vo
lta
g
e
co
lla
p
s
e
p
r
ed
ictio
n
u
s
in
g
a
n
ew lin
e
s
ta
b
ilit
y
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6.
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Evaluation Warning : The document was created with Spire.PDF for Python.
I
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.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
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p
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I
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6
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8
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zil,
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9
]
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0
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1
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2
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ra
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0
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5
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p
p
.
1
-
6
.
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3
]
M
.
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m
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m
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d
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n
d
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.
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tag
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ro
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p
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4
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5
]
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sirin
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a
n
d
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m
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n
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0
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[2
6
]
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p
p
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h
,"
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ter
n
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trica
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lec
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n
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&
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o
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n
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n
s,
2
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4
.
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7
]
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.
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m
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,
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.
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s
m
o
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sta
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l.
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1
)
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p
.
7
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-
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5
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8
9
.
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8
]
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p
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9
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5
.
[2
9
]
I.
A
.
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a
m
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e
l,
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ten
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e
,
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O.
A
.
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o
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p
e
,
A
.
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.
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l
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w
a
.
,
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re
d
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n
of
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l
tag
e
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a
p
se
in
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e
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tri
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t
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u
sin
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tag
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tab
il
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x
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ter
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n
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p
l
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g
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l.
1
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),
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p
.
1
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7
.
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0
]
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.
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.
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m
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su
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n
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ff
e
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ts
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f
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if
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a
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n
d
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d
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tw
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:
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e
rian
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k
v
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rid
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m
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r
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13
,
1
4
.
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ter
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ti
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n
fer
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p
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n
d
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PS
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2
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).
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a
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n
e
,
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tsw
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a
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2
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1
4
.
[3
1
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Nig
e
ria
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tri
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m
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issio
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e
Gr
id
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fo
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tricity
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.
[3
2
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O.
On
a
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a
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b
e
,
a
n
d
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.
A
p
e
h
,
"
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ty
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tri
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3
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1
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9
.
[3
4
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T
CN,
Da
il
y
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Rep
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rt
,
Os
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b
o
:
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Co
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p
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f
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ria (
T
CN),
2
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r
S
y
ste
m
Ne
t
w
o
rk
,
"
In
ter
n
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
El
e
c
trica
l
El
e
c
tro
n
ic
En
g
in
e
e
rin
g
S
tu
d
ies
,
v
o
l.
2
(
1
),
p
p
.
1
-
1
2
,
2
0
1
4
.
B
I
O
G
RAP
H
Y
O
F
AUTHO
RS
I.
A.
S
a
m
u
e
l
o
b
tain
e
d
h
is
P
h
D
E
lec
tri
c
a
l
a
n
d
El
e
c
tro
n
ics
E
n
g
in
e
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rin
g
f
ro
m
Co
v
e
n
a
n
t
Un
iv
e
rsit
y
,
Ota
,
Nig
e
ria,
w
h
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re
h
e
is
c
u
rre
n
tl
y
a
S
e
n
io
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L
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c
tu
re
r
in
t
h
e
De
p
a
rtme
n
t
o
f
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e
c
tri
c
a
l
&
In
f
o
r
m
a
ti
o
n
En
g
in
e
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rin
g
.
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re
se
a
rc
h
a
r
e
a
s
i
n
c
lu
d
e
p
o
w
e
r
s
y
ste
m
v
o
lt
a
g
e
sta
b
il
it
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a
n
d
o
p
e
ra
ti
o
n
,
re
li
a
b
il
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ty
,
a
n
d
m
a
in
ten
a
n
c
e
.
J
.
K
a
te
n
d
e
is
a
P
ro
f
e
ss
o
r
o
f
El
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c
tri
c
a
l
En
g
in
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rin
g
a
n
d
a
lec
tu
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r
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n
De
p
a
rtm
e
n
t
o
f
El
e
c
tri
c
a
l
a
n
d
Co
m
p
u
ter
En
g
in
e
e
rin
g
,
Na
m
ib
ia
Un
iv
e
rsit
y
o
f
S
c
ien
c
e
a
n
d
T
e
c
h
n
o
lo
g
y
,
W
in
d
h
o
e
k
,
Na
m
ib
ia
.
His
re
se
a
rc
h
a
re
a
s
in
c
lu
d
e
Ro
b
o
ti
c
s
a
n
d
a
u
t
o
m
a
t
io
n
;
p
o
w
e
r
s
y
st
e
m
a
n
d
c
o
n
tr
o
l;
m
o
d
e
ll
i
n
g
a
n
d
sim
u
latio
n
o
f
d
y
n
a
m
ica
l
s
y
ste
m
s;
a
n
d
re
n
e
w
a
b
le en
e
rg
y
.
C.
O
.
A.
Aw
o
so
p
e
is
a
P
ro
f
e
ss
o
r
o
f
El
e
c
tri
c
a
l
En
g
in
e
e
rin
g
a
n
d
a
lec
tu
re
r
in
th
e
De
p
a
rtme
n
t
o
f
El
e
c
tri
c
a
l
&
In
f
o
r
m
a
ti
o
n
En
g
in
e
e
r
in
g
,
Co
v
e
n
a
n
t
Un
iv
e
rsity
,
Ota
.
His
re
se
a
r
c
h
a
re
a
s
in
c
lu
d
e
P
o
w
e
r
s
y
ste
m
re
li
a
b
il
it
y
,
o
p
e
ra
ti
o
n
a
n
d
m
a
in
ten
a
n
c
e
.
A.
A.
Aw
e
le
w
a
o
b
tai
n
e
d
h
is
P
h
D
El
e
c
tri
c
a
l
a
n
d
El
e
c
tro
n
ic E
n
g
in
e
e
rin
g
f
ro
m
Co
v
e
n
a
n
t
Un
iv
e
rsit
y
,
Ota
,
Nig
e
ria,
w
h
e
re
h
e
is
c
u
rre
n
tl
y
a
S
e
n
io
r
L
e
c
tu
re
r
in
t
h
e
De
p
a
rtme
n
t
o
f
El
e
c
tri
c
a
l
&
In
f
o
r
m
a
ti
o
n
En
g
in
e
e
rin
g
.
His
re
se
a
r
c
h
a
re
a
s
i
n
c
lu
d
e
p
o
w
e
r
s
y
ste
m
sta
b
il
iza
ti
o
n
a
n
d
c
o
n
tr
o
l,
a
n
d
m
o
d
e
ll
in
g
a
n
d
sim
u
latio
n
o
f
d
y
n
a
m
ica
l
s
y
ste
m
s.
A.
I.
Ad
e
k
it
a
n
is
a
P
h
D
stu
d
e
n
t
stu
d
y
in
g
El
e
c
tri
c
a
l
/E
lec
tro
n
ic
s
En
g
in
e
e
rin
g
.
a
n
d
a
lec
tu
re
r
i
n
th
e
De
p
a
rt
m
e
n
t
o
f
El
e
c
tri
c
a
l
&
I
n
f
o
rm
a
ti
o
n
En
g
in
e
e
rin
g
,
Co
v
e
n
a
n
t
Un
iv
e
rsity
,
Ota
.
His
re
s
e
a
rc
h
a
re
a
in
c
lu
d
e
s p
o
w
e
r
s
y
st
e
m
,
o
p
e
ra
ti
o
n
a
n
d
re
li
a
b
il
it
y
.
F.
A.
Ag
b
e
tu
y
i
o
b
tain
e
d
h
is
P
h
D
El
e
c
tri
c
a
l
a
n
d
El
e
c
tro
n
ics
En
g
in
e
e
rin
g
f
ro
m
Co
v
e
n
a
n
t
Un
iv
e
rsit
y
,
Ota
,
Ni
g
e
ria,
w
h
e
re
h
e
is
c
u
rre
n
tl
y
a
S
e
n
io
r
L
e
c
tu
re
r
in
th
e
De
p
a
rt
m
e
n
t
o
f
El
e
c
tri
c
a
l
&
In
f
o
rm
a
ti
o
n
En
g
i
n
e
e
rin
g
.
His
re
se
a
rc
h
a
re
a
s
in
c
lu
d
e
Re
n
e
w
a
b
le
En
e
rg
y
,
m
icro
g
rid
,
p
o
w
e
r
s
y
st
e
m
sta
b
il
it
y
si
m
u
latio
n
o
f
d
y
n
a
m
ic s
y
ste
m
s an
d
d
istri
b
u
te
d
g
e
n
e
ra
ti
o
n
.
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