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a.
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[
5
-
7
]
.
Desp
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n
ex
p
e
cted
ch
an
g
e,
at
t
h
e
s
a
m
e
ti
m
e
as
r
o
to
r
k
ee
p
s
r
o
tatin
g
a
n
d
a
h
ig
h
s
lip
o
cc
u
r
s
i
t
w
ill
p
r
o
v
id
e
co
n
d
itio
n
f
o
r
o
v
er
v
o
ltag
e
a
n
d
o
v
er
cu
r
r
en
t
in
th
e
r
o
to
r
cir
cu
it.
Un
d
er
th
ese
cir
cu
m
s
ta
n
ce
s
,
t
h
e
r
o
to
r
co
n
v
er
ter
co
u
ld
b
e
s
atu
r
ated
a
n
d
t
h
e
co
n
tr
o
l
o
v
e
r
th
e
co
n
v
er
te
r
w
ill
b
e
lo
s
t;
i
t
ca
n
also
in
cr
ea
s
e
t
h
e
i
n
d
u
c
ed
elec
tr
o
m
ag
n
eti
c
f
o
r
ce
o
f
th
e
r
o
to
r
,
d
a
m
ag
e
t
h
e
co
n
v
er
ter
,
a
n
d
i
n
cr
ea
s
e
t
h
e
v
o
ltag
e
i
n
d
c
b
u
s
o
r
ca
u
s
in
g
o
s
c
illatio
n
i
n
cu
r
r
en
ts
[
8
-
1
2
]
.
I
f
n
o
co
u
n
ter
m
ea
s
u
r
es
ar
e
ta
k
en
t
h
e
w
i
n
d
t
u
r
b
in
e
w
ill
tr
i
p
an
d
b
e
d
i
s
co
n
n
ec
ted
f
r
o
m
th
e
p
o
w
er
n
et
w
o
r
k
,
b
u
t
th
e
n
e
w
g
r
id
co
d
es
r
eq
u
ir
e
th
at
w
in
d
t
u
r
b
in
e
s
r
e
m
ai
n
co
n
n
ec
ted
to
th
e
g
r
id
d
u
r
in
g
v
o
ltag
e
d
ip
s
.
T
h
e
m
ai
n
o
b
j
ec
tiv
e
is
to
av
o
id
an
y
d
is
co
n
n
ec
tio
n
o
f
DFI
G
b
ec
au
s
e
o
f
v
o
lta
g
e
d
ip
s
.
I
n
o
r
d
er
to
ac
h
iev
e
lo
w
v
o
ltag
e
r
id
e
-
th
r
o
u
g
h
an
d
p
r
o
tect
th
e
v
u
l
n
er
ab
le
co
n
v
er
ter
o
f
DFI
G
f
r
o
m
o
v
er
c
u
r
r
en
t
an
d
o
v
er
v
o
lta
g
e,
v
ar
io
u
s
cr
o
w
b
ar
to
p
o
lo
g
ies
ca
n
b
e
e
m
p
lo
y
ed
[
1
3
-
1
5
]
.
T
h
e
m
ai
n
p
r
o
b
lem
w
it
h
cr
o
w
b
ar
is
th
e
r
e
ac
tiv
e
p
o
w
er
d
r
a
w
n
f
r
o
m
t
h
e
p
o
w
er
n
et
w
o
r
k
w
h
i
ch
i
s
a
g
ain
s
t
t
h
e
g
r
id
co
d
e
r
eq
u
ir
e
m
e
n
ts
.
T
h
e
f
i
n
al
s
o
lu
t
io
n
r
elies
o
n
u
s
in
g
a
n
ex
ter
n
al
h
ar
d
w
ar
e
lik
e
d
y
n
a
m
ic
v
o
ltag
e
r
es
to
r
er
(
DVR).
Dif
f
er
en
t
to
p
o
lo
g
ies
o
f
DV
R
ar
e
p
r
o
p
o
s
ed
an
d
u
tili
ze
d
f
o
r
DFI
G
-
b
a
s
ed
w
i
n
d
tu
r
b
in
e
s
y
s
te
m
s
[
1
6
-
1
9
]
.
T
h
ese
p
r
o
p
o
s
ed
s
o
lu
tio
n
s
u
s
e
d
c
-
l
in
k
e
n
er
g
y
s
to
r
ag
e
ele
m
e
n
t
w
h
ich
w
i
ll
r
esu
lt
in
e
m
b
ed
d
i
n
g
lar
g
e
ca
p
ac
ito
r
in
d
c
lin
k
.
T
h
ese
t
y
p
e
s
o
f
DV
R
i
n
cr
ea
s
e
th
e
co
s
t
an
d
ar
e
n
o
t
s
u
i
tab
le
f
o
r
lo
n
g
ti
m
e
o
p
er
atio
n
an
d
th
eir
ap
p
licati
o
n
s
ar
e
li
m
ited
.
T
h
is
p
ap
er
p
r
esen
t
s
an
i
m
p
r
o
v
ed
s
o
lu
tio
n
e
m
p
lo
y
i
n
g
a
DV
R
to
ac
h
iev
e
L
VR
T
ca
p
ab
ilit
y
o
f
DFI
G
-
b
ased
w
i
n
d
t
u
r
b
in
e
s
y
s
t
e
m
w
i
th
lo
w
er
co
s
t
,
less
v
o
lu
m
e,
les
s
w
eig
h
t a
n
d
in
d
ep
en
d
en
t
v
o
ltag
e
co
m
p
e
n
s
a
tio
n
.
2.
DYNA
M
I
C
M
O
DE
L
L
I
N
G
O
F
DF
I
G
UND
E
R
VO
L
T
A
G
E
D
I
P
S
A
s
i
m
p
li
f
ied
s
ch
e
m
at
ic
d
iag
r
a
m
o
f
DFI
G
is
s
h
o
w
n
in
Fig
u
r
e
1
.
T
h
er
e
ar
e
s
o
m
e
p
u
b
licatio
n
s
f
o
cu
s
in
g
o
n
t
h
e
c
h
ar
ac
ter
is
ti
cs
o
f
DFI
G
d
u
r
i
n
g
s
y
m
m
etr
ical
an
d
as
y
m
m
etr
ical
g
r
id
v
o
ltag
e
co
n
d
itio
n
s
.
Dif
f
er
en
t
t
y
p
es
o
f
t
h
ese
u
n
b
alan
ce
co
n
d
itio
n
s
w
h
ich
DFI
Gs
ar
e
s
u
b
j
ec
ted
an
d
th
e
co
n
tr
o
l
tech
n
iq
u
e
s
to
o
v
er
co
m
e
th
ese
p
r
o
b
le
m
s
ar
e
p
r
esen
ted
in
s
e
v
er
al
p
ap
er
s
[
2
0
-
2
8
]
.
T
h
is
an
al
y
s
is
is
co
m
p
o
s
ed
o
f
t
w
o
p
ar
ts
.
I
n
th
e
f
ir
s
t
p
ar
t
n
o
r
m
al
o
p
er
atio
n
o
f
t
h
e
DFI
G
w
ill
b
e
an
al
y
s
ed
an
d
th
e
s
ec
o
n
d
p
ar
t
d
is
cu
s
s
es
th
e
D
FIG
u
n
d
er
v
o
ltag
e
d
ip
s
.
G
r
i
d
D
F
I
G
Fig
u
r
e
1
.
Si
m
p
li
f
ied
s
c
h
e
m
e
o
f
a
DFI
G
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
PEDS
I
SS
N:
2
0
8
8
-
8
694
E
fficien
t A
p
p
r
o
a
ch
to
LVR
T C
a
p
a
b
ilit
y
o
f D
F
I
G
-
B
a
s
ed
W
in
d
Tu
r
b
in
es u
n
d
er S
ymm
etri
ca
l…
(
K
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r
a
s
h
A
z
iz
i
)
947
2
.
1
.
No
rm
a
l O
er
a
t
io
n o
f
DF
I
G
No
r
m
a
l
o
p
er
atio
n
o
f
DFI
G
is
co
n
s
id
er
ed
to
h
av
e
co
n
s
ta
n
t
s
tato
r
v
o
lta
g
e
i
n
p
h
ase,
a
m
p
l
itu
d
e
a
n
d
f
r
eq
u
en
c
y
t
h
e
s
ec
o
n
d
p
ar
t
r
ef
er
s
to
th
e
s
y
m
m
etr
ic
an
d
as
y
m
m
etr
ical
v
o
lta
g
e
d
ip
s
.
T
h
e
v
o
ltag
e
eq
u
atio
n
s
o
f
th
e
DFI
G
ca
n
b
e
r
ep
r
esen
ted
b
y
th
e
f
o
llo
w
i
n
g
t
w
o
eq
u
at
io
n
s
:
dt
d
i
R
v
s
s
s
s
s
s
s
(
1
)
dt
d
i
R
v
r
r
r
r
r
r
r
(
2
)
w
h
er
e
s
s
v
an
d
s
s
i
ar
e
th
e
s
tato
r
v
o
lta
g
e
an
d
c
u
r
r
en
t
s
p
ac
e
v
ec
to
r
s
,
r
r
v
an
d
r
r
i
ar
e
th
e
r
o
to
r
v
o
ltag
e
a
n
d
cu
r
r
en
t
s
p
ac
e
v
ec
to
r
s
an
d
s
s
an
d
r
r
ar
e
s
tato
r
an
d
r
o
to
r
f
lu
x
s
p
ac
e
v
ec
to
r
s
,
r
esp
ec
tiv
el
y
.
E
q
u
at
io
n
s
(
1
)
an
d
(
2
)
ar
e
r
ep
r
esen
ted
in
(
s
tato
r
)
an
d
DQ
(
r
o
to
r
)
r
ef
er
en
ce
f
r
a
m
es
r
esp
ec
ti
v
el
y
;
s
u
p
er
s
cr
ip
ts
“
s
”
an
d
“
r
”
in
d
icate
th
at
s
p
ac
e
v
ec
to
r
s
ar
e
r
ef
er
r
ed
to
s
tato
r
an
d
r
o
to
r
r
ef
er
e
n
ce
f
r
a
m
es.
T
h
e
s
tato
r
an
d
r
o
to
r
f
l
u
x
eq
u
at
io
n
s
r
elate
d
to
th
e
cu
r
r
en
t
s
ca
n
b
e
ex
p
r
ess
e
d
as f
o
llo
w
s
:
s
s
s
s
s
s
m
r
L
i
L
i
(
3
)
r
r
r
r
m
s
r
r
L
i
L
i
(
4
)
w
h
er
e
s
L
an
d
r
L
ar
e
th
e
s
tato
r
an
d
r
o
to
r
in
d
u
cta
n
ce
s
w
i
th
m
L
b
ein
g
t
h
e
m
a
g
n
et
izin
g
i
n
d
u
c
tan
ce
.
Fo
r
th
e
p
u
r
p
o
s
e
o
f
th
is
p
ap
er
,
th
e
p
ar
k
m
o
d
el
is
ap
p
lied
w
it
h
t
h
e
r
o
to
r
v
ar
iab
les
r
ef
er
r
ed
to
th
e
s
tato
r
.
E
q
u
atio
n
s
(
2
)
an
d
(
4
)
w
ill
b
e
r
e
w
r
itte
n
as
f
o
llo
w
s
(
f
o
r
s
i
m
p
l
icit
y
s
u
p
er
s
cr
ip
ts
“
s
”
in
d
icati
n
g
s
tatic
s
tato
r
r
ef
er
en
ce
f
r
a
m
e
i
s
o
m
itted
,
s
o
eq
u
atio
n
s
1
an
d
3
co
u
ld
b
e
ig
n
o
r
ed
o
f
r
e
w
r
iti
n
g
)
:
r
r
s
r
s
r
d
v
R
i
j
dt
(
5
)
r
r
r
m
s
L
i
L
i
(
6
)
w
h
er
e
s
is
th
e
s
y
n
c
h
r
o
n
o
u
s
an
g
u
lar
f
r
eq
u
e
n
c
y
.
T
h
e
r
o
to
r
v
o
ltag
e
o
w
i
n
g
to
s
tato
r
v
o
ltag
e
ca
n
b
e
ex
p
r
ess
ed
as:
m
r
s
r
r
m
r
s
L
d
v
v
s
R
L
j
i
L
d
t
(
7
)
T
h
is
is
a
ls
o
t
h
e
v
o
ltag
e
g
e
n
er
ated
b
y
t
h
e
co
n
v
er
ter
w
h
er
e
“
s
”
is
t
h
e
s
lip
(
)
,
m
s
r
s
r
s
,
σ
is
t
h
e
leak
ag
e
f
ac
to
r
,
r
an
d
m
ar
e
th
e
s
y
n
ch
r
o
n
o
u
s
a
n
d
elec
tr
ical
an
g
u
lar
f
r
eq
u
en
c
y
;
r
esp
ec
ti
v
el
y
.
B
y
n
e
g
lecti
n
g
th
e
r
esis
tan
ce
r
R
an
d
th
e
lea
k
ag
e
f
ac
to
r
σ
(
b
ec
au
s
e
o
f
th
eir
s
m
al
l v
alu
e)
,
eq
u
at
io
n
(
7
)
w
ill b
e
m
o
r
e
s
i
m
p
li
f
ied
:
jt
mm
r
s
r
n
r
s
s
s
s
s
LL
v
j
V
e
LL
(
8
)
jt
m
s
r
n
s
s
L
v
s
V
e
L
(
9
)
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8
694
IJ
PEDS
Vo
l.
8
,
No
.
2
,
J
u
n
e
2
0
1
7
:
9
4
5
–
9
5
6
948
rn
v
I
s
th
e
r
o
to
r
v
o
ltag
e
in
w
h
ic
h
t
h
e
ter
m
s
s
m
V
L
L
s
w
il
l b
e
co
n
s
id
er
ed
as th
e
a
m
p
li
tu
d
e
o
f
rn
v
,
f
r
o
m
E
q
u
atio
n
9
it is
o
b
v
io
u
s
th
at
t
h
e
r
o
to
r
v
o
ltag
e
d
ep
en
d
s
o
n
s
t
ato
r
v
o
ltag
e
an
d
t
h
e
s
lip
.
2
.
2
.
Sy
mm
et
rica
l V
o
lt
a
g
e
Di
ps
I
n
t
h
e
s
tead
y
s
tate,
t
h
e
s
tato
r
f
l
u
x
is
p
r
o
p
o
r
tio
n
al
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h
e
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tat
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r
v
o
ltag
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at
is
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u
n
d
er
a
lo
n
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en
o
u
g
h
ti
m
e
o
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v
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ip
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s
tato
r
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o
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ll
r
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o
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n
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s
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ar
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it
w
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ll
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p
o
n
e
n
tia
ll
y
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ec
r
ea
s
e
to
ze
r
o
.
0
1
t
m
s
r
n
m
ss
L
v
j
e
L
(
10
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W
h
er
e
0
is
th
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itial
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tato
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f
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R
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th
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r
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s
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o
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r
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r
e
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el
y
w
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th
r
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g
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lar
f
r
eq
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e
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c
y
m
an
d
h
as
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an
s
ie
n
t ti
m
e
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ep
en
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g
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n
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h
e
m
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n
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n
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tan
t.
0
1
t
jt
m
r
m
s
r
n
m
ss
L
v
j
e
e
L
(
11
)
As th
e
ter
m
s
1
is
r
elativ
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s
m
al
l,
th
e
a
m
p
lit
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d
e
o
f
t
h
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v
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g
e
w
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l b
e
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1
m
m
m
r
n
s
s
s
s
s
LL
V
V
s
V
LL
(
12
)
T
h
e
in
d
u
ce
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v
o
ltag
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o
n
t
h
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r
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to
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w
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n
d
in
g
s
d
u
r
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g
s
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o
r
t
cir
cu
it
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i
m
ilar
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tato
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e
to
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n
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ain
t
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r
s
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p
er
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s
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n
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o
n
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s
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p
ee
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th
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d
er
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e
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o
r
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itio
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ate
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a
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i
m
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m
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g
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ated
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th
at
is
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i
m
ilar
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ter
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ize
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r
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ato
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s
u
b
j
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tial
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ip
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-
1
2
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atin
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m
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o
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s
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l
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x
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ar
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p
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io
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tio
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m
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p
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tial
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ip
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l
u
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lar
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n
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n
t
2
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2
2
t
jt
s
s
s
ss
s
s
f
s
n
ss
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V
V
t
e
e
jj
(
13
)
W
h
er
e
2
sf
is
th
e
f
o
r
ce
d
f
lu
x
r
elate
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to
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tato
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ltag
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ch
a
n
g
i
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g
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r
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m
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V
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w
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ter
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(
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m
ilar
to
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n
d
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ce
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d
u
r
in
g
n
o
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al
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A
C
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g
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w
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h
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r
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p
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r
tio
n
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d
th
e
s
ta
to
r
v
o
ltag
e:
2
jt
m
s
r
f
s
s
L
v
V
s
e
L
(
14
)
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
PEDS
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(
16
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1
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(
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r
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as f
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jt
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r
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r
r
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s
s
s
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s
V
V
e
e
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(
18
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h
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t
ter
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f
t
h
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p
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ev
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d
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tio
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12
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11
2
j
s
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m
s
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v
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L
(
20
)
2
22
22
j
s
t
m
s
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s
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v
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L
(
21
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Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
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8
8
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8
694
IJ
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3.
DYNA
M
I
C
VO
L
T
A
G
E
RE
ST
O
R
E
R
(
DVR)
T
o
o
v
er
co
m
e
th
e
a
f
o
r
e
m
e
n
tio
n
ed
v
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lta
g
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d
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s
p
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b
lem
s
,
D
VR
ca
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b
e
t
h
e
b
est
ec
o
n
o
m
ica
l
an
d
tech
n
ical
s
o
lu
tio
n
.
Sev
er
al
ar
ticles
o
n
t
h
is
to
p
ic
h
a
v
e
ad
d
r
ess
ed
ap
p
ly
i
n
g
DV
R
s
[
1
6
-
1
9
,
2
9
]
.
I
n
th
e
p
r
ev
io
u
s
p
ap
er
s
,
as
m
e
n
tio
n
ed
,
th
e
ex
is
ti
n
g
o
f
e
n
er
g
y
s
to
r
ag
e
ele
m
e
n
t
s
in
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i
s
co
n
s
id
er
ed
as
a
d
is
ad
v
an
ta
g
e,
s
u
c
h
as
n
o
lo
n
g
ti
m
e
v
o
lta
g
e
co
m
p
e
n
s
ati
n
g
,
h
ig
h
er
co
s
t
a
n
d
v
o
lu
m
e,
li
m
it
ed
ap
p
licatio
n
.
T
h
e
p
r
o
p
o
s
ed
DVR
co
n
s
is
t
s
o
f
th
r
ee
in
d
ep
en
d
en
t
th
r
ee
-
p
h
ase
to
s
in
g
le
-
p
h
ase
d
ir
ec
t
co
n
v
er
ter
s
w
h
ic
h
ca
n
o
p
er
ate
in
d
ep
en
d
en
tl
y
.
As
ea
c
h
co
n
v
e
r
ter
o
p
er
ates
in
d
ep
en
d
en
tl
y
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n
d
th
e
co
m
p
e
n
s
atio
n
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ltag
e
f
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r
an
y
f
a
u
lt
y
p
h
a
s
e
o
r
p
h
ases
is
tak
e
n
f
r
o
m
all
th
r
ee
p
h
ase
o
r
p
h
ases
,
th
e
p
r
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p
o
s
ed
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ca
n
o
p
er
ate
r
eg
ar
d
less
o
f
t
h
e
f
a
u
lt
t
y
p
e
an
d
ca
n
co
m
p
en
s
ate
j
u
s
t
t
h
e
f
au
lt
y
p
h
ase
(
o
r
p
h
ases
)
.
Mo
r
eo
v
er
,
n
o
d
c
-
lin
k
r
esu
lts
i
n
lo
n
g
ti
m
e
co
m
p
en
s
atio
n
an
d
co
n
s
id
er
ab
le
r
ed
u
ctio
n
i
n
co
s
t
an
d
p
h
y
s
ical
v
o
l
u
m
e.
I
n
ad
d
itio
n
a
n
in
j
ec
tio
n
tr
a
n
s
f
o
r
m
er
w
i
th
a
t
u
r
n
s
r
atio
o
f
1
:
a
(
a
f
o
r
g
r
id
s
id
e)
,
an
L
C
fi
lter
,
a
b
y
p
as
s
s
w
i
tch
(
to
b
y
p
as
s
t
h
e
DV
R
u
n
d
er
n
o
r
m
a
l
o
p
er
atio
n
)
ar
e
u
s
ed
.
Fi
g
u
r
e
2
s
h
o
w
s
t
h
e
s
c
h
e
m
a
tic
d
iag
r
a
m
o
f
o
n
e
o
f
t
h
e
t
h
r
ee
i
n
d
ep
en
d
en
t
co
n
v
er
t
er
s
,
th
e
o
t
h
er
t
w
o
co
n
v
er
ter
s
ar
e
th
e
s
a
m
e.
T
h
e
co
m
m
o
n
-
e
m
i
tter
an
tip
ar
allel
I
GB
T
s
w
it
h
a
d
io
d
e
-
p
air
ar
r
an
g
e
m
e
n
t
h
av
e
b
ee
n
u
tili
ze
d
f
o
r
th
e
p
u
r
p
o
s
e
o
f
th
i
s
p
ap
er
an
d
all
th
ese
s
w
itc
h
es
ar
e
ass
u
m
ed
to
b
e
id
ea
l.
B
y
ap
p
ly
i
n
g
DVR
to
a
DFI
G,
th
e
v
o
lta
g
e
ac
r
o
s
s
t
h
e
s
tato
r
b
ec
o
m
es:
s
g
i
n
j
v
t
v
t
v
t
(
32
)
W
h
er
e
t
v
s
,
t
v
g
an
d
t
v
i
n
j
ar
e
t
h
e
i
n
s
tan
ta
n
eo
u
s
s
ta
to
r
,
g
r
id
a
n
d
DV
R
i
n
j
ec
ted
v
o
ltag
e
s
,
r
esp
ec
ti
v
el
y
.
Un
d
er
n
o
r
m
a
l
o
p
er
atio
n
s
,
D
VR
i
s
b
y
p
as
s
ed
b
y
clo
s
i
n
g
th
e
s
w
itc
h
“K”
.
Hi
g
h
f
r
eq
u
en
c
y
p
u
ls
e
w
id
t
h
m
o
d
u
latio
n
is
ap
p
lied
to
th
e
DVR
i
n
o
r
d
er
to
c
o
n
tr
o
l
th
e
u
s
ed
co
n
v
er
ter
s
.
E
ac
h
s
a
m
p
li
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h
ic
h
r
esu
l
t
in
i
n
d
ep
en
d
en
t
o
p
er
atio
n
o
f
th
r
ee
d
ir
ec
t
co
n
v
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ter
s
an
d
as
m
e
n
tio
n
ed
,
b
ec
au
s
e
o
f
n
o
d
c
-
lin
k
;
lo
n
g
-
ter
m
co
m
p
en
s
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n
,
a
g
r
ea
t
d
ec
r
ea
s
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in
co
s
t,
w
ei
g
h
t,
a
n
d
v
o
l
u
m
e
is
o
b
tain
ed
.
B
y
ap
p
ly
in
g
t
h
e
DV
R
,
t
h
e
L
V
R
T
ca
p
ab
ilit
y
o
f
DFI
G
-
b
ased
w
in
d
tu
r
b
i
n
es
ar
e
i
m
p
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v
e
d
an
d
t
h
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s
tab
le
o
p
er
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n
o
f
DFI
Gs
ar
e
g
u
ar
a
n
teed
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T
h
e
b
eh
av
io
u
r
o
f
DFI
G
an
d
DV
R
u
n
d
er
th
r
ee
-
p
h
ase,
p
h
a
s
e
-
p
h
ase,
a
n
d
s
i
n
g
le
p
h
ase
v
o
lta
g
e
d
ip
s
w
it
h
t
h
e
d
ep
th
o
f
4
0
%
ar
e
s
im
u
lated
w
h
ic
h
s
h
o
w
t
h
e
ef
f
ec
tiv
e
n
ess
o
f
t
h
e
DVR
s
y
s
te
m
i
m
p
r
o
v
in
g
th
e
L
V
R
T
ca
p
ab
ilit
y
o
f
DFI
G.
RE
F
E
R
E
NC
E
S
[1
]
Blaa
b
jerg
,
F
.
,
&
M
a
,
K
.
(2
0
1
3
).
F
u
tu
re
o
n
p
o
w
e
r
e
lec
tro
n
ics
f
o
r
w
in
d
tu
rb
in
e
sy
ste
m
s
.
IEE
E
J
o
u
rn
a
l
o
f
Eme
rg
in
g
a
n
d
S
e
lec
ted
T
o
p
ics
in
P
o
we
r E
le
c
tro
n
ics
,
1
(
3
),
1
3
9
-
1
5
2
.
[2
]
A
n
a
y
a
-
L
a
ra
,
O.,
Je
n
k
in
s,
N.,
Ek
a
n
a
y
a
k
e
,
J.,
Ca
rt
w
rig
h
t,
P
.
,
&
Hu
g
h
e
s,
M
.
(2
0
1
1
).
W
in
d
e
n
e
rg
y
g
e
n
e
ra
ti
o
n
:
m
o
d
e
ll
in
g
a
n
d
c
o
n
tro
l.
Jo
h
n
W
il
e
y
&
S
o
n
s.
[3
]
M
u
rth
y
,
S
.
S
.
,
S
in
g
h
,
B.
,
G
o
e
l,
P
.
K.,
&
T
i
w
a
ri,
S
.
K.
(2
0
0
7
,
No
v
e
m
b
e
r).
A
c
o
m
p
a
ra
ti
v
e
stu
d
y
o
f
f
ix
e
d
sp
e
e
d
a
n
d
v
a
riab
le
sp
e
e
d
w
in
d
e
n
e
rg
y
c
o
n
v
e
rsio
n
sy
ste
m
s
f
e
e
d
in
g
th
e
g
rid
.
In
2
0
0
7
7
t
h
In
ter
n
a
ti
o
n
a
l
Co
n
fer
e
n
c
e
o
n
Po
we
r
El
e
c
tro
n
ics
a
n
d
Dr
ive
S
y
ste
ms
(
p
p
.
7
3
6
-
7
4
3
).
IEE
E.
[4
]
Ju
sto
,
J.
J.,
M
w
a
silu
,
F
.
,
&
Ju
n
g
,
J.
W
.
(2
0
1
5
).
Do
u
b
ly
-
fe
d
in
d
u
c
ti
o
n
g
e
n
e
ra
to
r
b
a
se
d
w
in
d
tu
r
b
i
n
e
s:
A
c
o
m
p
re
h
e
n
siv
e
re
v
ie
w
o
f
f
a
u
lt
rid
e
-
th
ro
u
g
h
stra
teg
i
e
s.
Ren
e
wa
b
le
a
n
d
S
u
st
a
in
a
b
le E
n
e
rg
y
Rev
iews
,
4
5
,
4
4
7
-
4
6
7
.
[5
]
Kim
u
ra
,
N.,
Ha
m
a
d
a
,
T
.
,
S
o
n
o
d
a
,
M
.
,
M
o
r
iza
n
e
,
T
.
,
T
a
n
ig
u
c
h
i,
K.,
&
Nish
id
a
,
Y.
(2
0
0
9
,
M
a
y
).
S
u
p
p
re
ss
io
n
o
f
c
u
rre
n
t
p
e
a
k
o
f
P
F
C
c
o
n
v
e
rter co
n
n
e
c
ted
t
o
i
n
d
u
c
ti
o
n
g
e
n
e
ra
to
r
f
o
r
w
in
d
p
o
w
e
r
g
e
n
e
ra
ti
o
n
e
x
c
it
e
d
b
y
v
o
lt
a
g
e
so
u
rc
e
c
o
n
v
e
rter.
In
Po
we
r
El
e
c
tro
n
ics
a
n
d
M
o
t
io
n
Co
n
tro
l
Co
n
fer
e
n
c
e
,
2
0
0
9
.
IP
EM
C'
0
9
.
IEE
E
6
t
h
In
ter
n
a
ti
o
n
a
l
(
p
p
.
2
2
6
9
-
2
2
7
4
).
IEE
E.
[6
]
Bre
k
k
e
n
,
T
.
,
&
M
o
h
a
n
,
N.
(2
0
0
3
,
Ju
n
e
).
A
n
o
v
e
l
d
o
u
b
ly
-
f
e
d
in
d
u
c
ti
o
n
w
in
d
g
e
n
e
ra
to
r
c
o
n
tro
l
sc
h
e
m
e
f
o
r
re
a
c
ti
v
e
p
o
w
e
r
c
o
n
tro
l
a
n
d
to
r
q
u
e
p
u
lsa
ti
o
n
c
o
m
p
e
n
sa
ti
o
n
u
n
d
e
r
u
n
b
a
lan
c
e
d
g
rid
v
o
lt
a
g
e
c
o
n
d
it
i
o
n
s.
In
Po
we
r
El
e
c
tro
n
ics
S
p
e
c
ia
li
st
Co
n
fer
e
n
c
e
,
2
0
0
3
.
PE
S
C'
0
3
.
2
0
0
3
IEE
E
3
4
th
An
n
u
a
l(
Vo
l.
2
,
p
p
.
7
6
0
-
7
6
4
).
IEE
E.
[7
]
Blaa
b
jerg
,
F
.
,
&
Ch
e
n
,
Z.
(2
0
0
5
).
P
o
w
e
r
e
lec
tro
n
ics
f
o
r
m
o
d
e
rn
w
in
d
tu
rb
in
e
s.S
y
n
th
e
sis
L
e
c
t
u
re
s
o
n
P
o
w
e
r
El
e
c
tro
n
ics
,
1
(1
),
1
-
68.
[8
]
A
n
a
n
th
,
D.
V
.
N.,
&
Ku
m
a
r,
G
.
N.
(2
0
1
6
)
.
P
e
rf
o
r
m
a
n
c
e
E
v
a
lu
a
ti
o
n
o
f
DFIG
Du
rin
g
As
y
m
m
e
tri
c
a
l
G
rid
Distu
rb
a
n
c
e
s
Us
in
g
In
tern
a
l
M
o
d
e
l
Co
n
t
ro
ll
e
r
a
n
d
Re
so
n
a
n
t
Co
n
tr
o
ll
e
r.
In
ter
n
a
ti
o
n
a
l
J
o
u
rn
a
l
o
n
El
e
c
trica
l
En
g
i
n
e
e
rin
g
a
n
d
I
n
fo
rm
a
ti
c
s,
8
(
3
),
4
9
4
.
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