In
te
r
n
ation
a
l Jou
rn
al
o
f Po
we
r
Elec
tron
ic
s an
d
D
r
ive S
y
stem
(IJ
PED
S
)
V
o
l.
10, N
o.
3, S
ep 2019,
pp.
1
1
5
7
~1
1
6
6
ISSN: 2088-
8694,
DOI
:
10.11591
/ijpeds.
v10.
i
3.pp1157-1166
1157
Jou
rn
a
l
h
o
me
pa
ge
:
ht
tp:
//i
a
e
score
.
com
/
j
o
u
r
na
l
s
/
i
n
d
e
x
.
p
hp/IJ
PED
S
Comparative stud
y of
two poten
tial recup
erating converters in
DC rail
way electrification sys
tem
for harmonic m
itigation
Z. H
. Choi,
C
. L.
T
o
h
,
M
.
H
.
Z. Hi
l
mi
D
e
part
men
t
o
f Electri
cal P
o
w
er E
ng
ineeri
ng, Univ
e
rsiti Ten
a
g
a
N
at
io
nal, M
alaysi
a
Art
i
cl
e In
fo
ABSTRACT
A
r
tic
le hist
o
r
y
:
R
e
c
e
i
v
e
d
No
v
2
5
,
2
018
Re
vise
d F
e
b 12,
201
9
Ac
ce
p
t
ed
M
ar 8
, 2
0
19
The
re
ge
ne
ra
tiv
e
b
ra
king
e
n
e
rg
y
pro
d
u
c
e
d
by
Lig
h
t
-Ra
i
l-
Tra
n
sit
(L
R
T
)
t
r
ai
n
is
c
omm
o
n
l
y
t
r
a
n
sf
erred
back
t
o
po
wer
g
r
id
v
i
a
a
c
on
ven
tio
nal
t
h
r
ee-ph
as
e
in
vert
er
(recu
pe
r
a
ti
ng
c
o
n
v
e
rter).
A
l
t
h
o
u
g
h
t
h
i
s
i
s
a
cos
t
s
av
i
ng
s
olut
io
n
bu
t
th
e
ac
gri
d
c
urr
e
n
t
a
n
d
v
o
l
t
a
ge
w
av
ef
orm
s
w
e
r
e
di
st
orted
.
H
en
ce
p
a
s
s
i
v
e
filters
a
re
i
ntegrated
t
o
m
i
t
igat
e
the
harmonics.
T
his
paper
pr
op
os
ed
t
o
repl
ace
t
h
e
c
o
n
v
en
tio
nal
in
ve
rt
er
s
y
s
t
e
m
with
a
m
ul
tilevel
co
nv
ert
e
r.
Cascaded
H
-Bri
dge
(CH
B
)
converte
r
a
n
d
Mo
du
la
r
Mul
tile
v
e
l
C
on
ve
r
te
r
(M
M
C
)
are
sel
e
cted
t
o
be
e
v
a
l
u
at
ed
i
n
this
p
a
p
er
d
u
e
t
o
th
eir
m
od
ul
a
r
ity
st
ruct
ures.
Th
e
a
i
m
o
f
t
his
s
t
ud
y
is
t
o
d
e
termin
e
the
mo
st
p
ot
e
nt
i
a
l
mu
ltilevel
convert
e
r
t
o
b
e
imp
l
emented
w
ithout
a
ddition
a
l
passive
f
i
l
t
ers.
N
ine-level
CHB
and
nin
e
-level
M
M
C
c
on
verter
s
are
m
odeled
with
M
A
TLA
B/Sim
u
l
i
nk
simul
a
tion
too
l
.
Both
c
onvert
er
s
are
m
o
d
u
l
a
ted
with
L
evel-Sh
i
f
t
ed
P
u
l
s
e
Wi
d
t
h
Mo
du
latio
n
t
echn
i
qu
e.
T
he
o
u
t
p
u
t
volt
a
ge
a
n
d
c
urren
t
w
ave
fo
r
m
s
g
e
n
e
r
a
t
e
d
b
y
C
H
B
a
n
d
M
M
C
a
r
e
p
r
e
s
e
n
t
e
d
w
i
t
h
f
u
l
l
a
n
a
l
y
s
i
s
.
I
t
i
s
con
c
lu
ded
t
h
at
M
M
C
c
o
n
v
e
rter
i
s
m
o
re
s
u
i
t
a
bl
e
t
o
b
e
us
ed
a
s
a
r
ecu
per
a
t
i
ng
con
v
ert
e
r.
I
t
prod
uces
a
c
lea
n
v
ol
tag
e
a
n
d
curren
t
w
avef
o
r
m
s
.
T
he
vo
lt
age
an
d
cu
r
r
ent
To
ta
l
Harm
o
n
ic
D
i
s
to
rti
o
n
(TH
D
)
i
n
d
e
xes
are
f
ou
nd
app
r
ox
im
ate t
o
8
%
and
3%.
K
eyw
ord
s
:
Re
c
uper
a
t
i
ng
con
v
er
ter
Mo
du
la
r m
u
ltil
eve
l
c
o
n
v
er
t
e
r
Ca
sca
d
e
d
H
-
b
ridge
c
o
n
ve
r
t
er
Leve
l
-
sh
ifte
d
PW
M
H
a
r
m
onic
miti
gat
i
on
Co
pyri
gh
t © 2
019 In
stit
u
t
e
of Advanced
En
gi
neeri
n
g
an
d
S
c
ien
ce.
All
rights
res
e
rv
ed.
Corres
pon
d
i
n
g
Au
th
or:
C
.
L. Toh,
D
e
pa
rtme
nt
o
f
El
e
c
t
rica
l
P
o
w
e
r Engi
nee
r
i
n
g
,
Uni
v
ersi
ti
T
e
n
aga
Na
si
o
n
a
l
,
Jala
n
Ikram-U
n
ite
n,
430
0
0
K
a
j
an
g,
S
ela
n
g
o
r
,
M
a
l
ay
si
a
Em
ail:
chue
n
l
i
n
g
@
uni
ten.
ed
u
.
m
y
1.
I
N
TR
OD
U
C
TI
O
N
D
C
r
a
i
l
w
a
y
e
l
e
c
t
r
i
f
i
c
a
t
i
o
n
s
y
s
t
e
m
i
s
n
o
r
m
a
l
l
y
u
s
e
d
t
o
p
o
w
e
r
u
p
t
h
e
c
o
m
m
uter
t
r
a
ins,
s
uch
a
s
t
r
a
m
,
Lig
h
t
-R
ail
-
Tra
n
si
t
(LR
T
)
an
d
M
a
ss-R
a
pid
-
Tran
si
t
(MR
T
)
in
u
rb
an
ci
ti
es
[
1
]
.
A
t
r
am
a
nd
L
ig
h
t
-R
ail
-
Tra
n
si
t
(LRT)
syste
m
a
re
d
esig
ne
d
t
o
c
om
mute
l
o
w
capa
c
i
t
y
of
p
a
s
se
n
g
e
r
in
a
t
ra
ve
l
l
i
n
g
s
p
e
e
d
bel
o
w
70
k
m
per
ho
ur.
H
e
nce
,
t
he
D
C
vo
l
t
a
g
e
su
pp
l
y
i
s
ra
te
d
a
t
7
5
0
V
.
O
n
t
he
o
t
he
r
ha
nd,
a
M
ass-
Ra
pi
d-Tr
ans
i
t
(
M
RT)
sy
st
em may
e
mp
l
o
y
a
hi
gh
e
r
DC
v
o
lta
ge rati
n
g (1.
5
kV
or 3 kV
)
t
o com
m
u
t
e
h
ig
her
ca
pac
i
t
y
o
f passe
nge
r. In
gene
ra
l,
M
RT
t
r
a
in is c
a
pa
b
l
e
to tra
ve
l
i
n
t
he
s
pe
e
d
a
bo
ve 7
0
k
m
per
hour.
A
ll
t
y
pes
o
f
c
om
mute
r
t
r
ai
n
s
w
i
l
l
ex
per
i
e
n
ce
f
our
o
pera
t
i
n
g
m
od
e
s
t
o
m
ove
f
r
o
m
on
e
pa
sse
n
ger
st
a
tio
n
to
t
he
s
ub
se
que
nt
s
ta
t
i
o
n
[
2].
The
s
e
o
p
er
at
in
g
m
ode
s
i
n
c
l
ude
a
c
cele
r
at
in
g
mo
de
,
m
o
t
o
ri
ng
m
ode
,
c
o
ast
i
ng
m
o
d
e
a
n
d
b
raki
ng
m
o
d
e
.
Up
on
d
epa
r
t
u
re
,
ma
ssi
v
e
e
l
e
ct
ri
c
p
o
w
e
r
w
i
l
l
b
e
d
r
awn
t
o
a
cc
el
era
t
e
a
t
r
ain
from
s
t
a
n
d
st
il
l
to
t
he
d
em
an
ded
l
i
ne
s
pe
e
d
.
The
tra
i
n
w
i
l
l
t
he
n
s
h
i
fte
d
t
o
m
o
tor
i
ng
m
ode
a
n
d
t
rave
ls
a
t
a
con
s
ta
n
t
s
pe
ed.
Whe
n
t
he
t
rai
n
i
s
pre
p
a
r
ed
t
o
a
rrive
a
t
the
ne
x
t
passe
n
g
e
r
s
ta
ti
o
n
,
i
t
w
i
l
l
firs
t
en
tere
d
c
o
astin
g
mode
.
I
n
t
h
i
s
m
o
de
,
t
h
e
e
l
ec
tric
m
o
t
or
i
s
n
o
t
be
ing
e
n
er
gi
ze
d;
the
t
r
ai
n
is
m
ove
d
by
i
ts
m
om
ent
u
m
w
i
t
h
t
h
e
spee
d
dr
o
ppi
n
g
a
c
c
ord
i
ng
l
y
due
t
o
t
h
e
fric
tio
n
for
ce.
E
ve
nt
ua
ll
y,
t
he
b
r
a
kin
g
m
ode
w
ill
be
a
c
tiva
t
ed
t
o
s
t
op
the tra
i
n ac
cura
tel
y
at
t
h
e
pa
sse
nge
r sta
t
i
on. A
tra
in w
il
l
ac
t
as a ge
nera
tor in br
a
ki
n
g
m
od
e w
h
ere
abou
t 44 %
– 56
%
of
r
ege
n
e
r
ati
v
e
brak
in
g
e
n
ergy
can
b
e
rec
o
ve
red
[3-5
].
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SSN: 2088-
8694
Int J
P
o
w
El
e
c
&
D
ri S
yst
,
V
ol.
10,
N
o.
3
, S
e
p
2
0
1
9
:
115
7
– 1
166
1
158
Ma
jori
t
y
o
f
t
h
e
D
C
t
rac
tio
n
pow
er
s
u
b
st
a
t
i
on
i
s
d
es
i
gne
d
w
ith
r
ec
tifier
tra
n
sform
e
r
coup
le
w
i
t
h
a
tw
el
ve-p
ulse
t
r
a
c
tio
n
rec
t
i
f
i
e
r
(unco
n
t
ro
lle
d)
[
6].
This
d
es
i
g
n
i
s
ca
pa
bl
e
t
o
r
egu
l
ate
a
nom
ina
l
D
C
v
o
lta
ge
f
or
com
m
ute
r
t
r
a
i
n
s
o
p
er
at
ion.
T
h
e
a
d
v
an
ta
ge
o
f
th
is
c
o
n
f
ig
ura
tio
n
is
t
o
ke
e
p
t
h
e
t
o
t
a
l
h
ar
m
onic
di
s
t
ort
i
o
n
o
f
the
A
C
l
ine
c
u
rre
n
t
i
n
t
h
e
ac
ce
p
t
a
n
ce
ra
ng
e
of
s
t
a
nda
r
d
[
7].
H
o
w
e
ve
r,
t
his
c
o
n
f
ig
ura
tio
n
d
o
es
n
o
t
f
ul
ly
u
t
i
l
i
z
e
th
e
brak
in
g
ene
r
g
y
.
T
he
t
r
acti
on
r
e
ctif
i
e
r
on
ly
s
upp
or
t
s
u
n
i
di
r
e
c
t
i
o
n
a
l
c
u
r
r
e
n
t
f
l
o
w
.
A
s
a
r
e
s
u
l
t
,
t
h
e
r
e
g
e
n
e
r
a
t
i
v
e
brak
in
g
ene
r
g
y
has
to
b
e
d
i
ss
i
p
ate
d
t
hro
u
gh
some
r
esistor
ban
k
s
[
8,
9
]
.
S
om
e
r
e
sea
r
ch
w
or
ks
h
a
v
e
prop
ose
d
to
u
ti
l
i
ze
the
rege
nera
tive
en
er
gy
t
o
r
egu
l
a
t
e
t
h
e
forw
ard
t
r
a
i
n
v
o
lta
ge
[
1
0
],
pow
er
up
t
h
e
a
u
x
i
l
i
ary
lo
a
d
s
in
passe
nge
r
sta
t
i
on
[1
1]
o
r in
t
ra
i
n
s [1
2].
In orde
r
t
o rea
liz
e
t
he
a
b
ove
me
n
t
i
one
d pro
p
o
sa
ls
, t
h
e
e
x
i
s
t
i
n
g
tr
a
c
tio
n
sub
s
ta
tio
n ha
s
to be
u
p
g
rade
d
w
ith a
r
ec
upera
tin
g
con
v
erte
r
.
A
c
o
s
t
s
a
v
i
n
g
s
o
l
u
t
i
o
n
i
s
t
o
t
r
a
n
s
f
e
r
t
h
e
p
o
w
e
r
b
a
c
k
t
o
t
h
e
g
r
i
d
[1
3,
1
4]
.
A
s
s
how
n
in
F
igure
1
(a)
,
t
h
e
e
x
i
s
ti
ng
t
r
act
ion
re
ct
if
i
e
r
a
n
d
re
ct
i
f
i
e
r
t
r
an
sfo
r
me
r
a
r
e
r
e
m
a
i
n
u
n
c
h
a
n
ge
d.
A
n
A
c
t
i
v
e
Re
ge
nera
t
i
o
n
U
n
i
t
(A
RU
),
w
hich
c
on
sis
t
s
o
f
a
c
on
ve
n
t
i
ona
l
t
h
ree
-
phase
i
n
v
e
r
t
e
r
a
n
d
LC
f
il
ter,
i
s
ad
de
d
to
t
he
e
x
i
s
t
i
n
g
s
y
s
t
em
.
The
D
C
t
e
r
m
i
na
l
o
f
t
he
A
RU
i
s
c
o
nnec
t
e
d
t
o
the
trac
t
i
on
l
oa
d.
W
here
as
t
he
A
C
ter
m
inal
o
f
t
h
e
ARU
is
ho
o
k
ed
u
p
to
t
he
s
ec
o
nda
ry
s
i
d
e
of
t
he
r
ec
t
i
fie
r
t
ra
n
s
form
er
a
t
s
ta
r
w
i
nd
ing.
I
n
[1
5],
a
t
h
r
ee
phas
e
rege
nera
t
i
ve
i
n
v
e
r
ter
is
d
es
i
g
ned
for
a
D
C
t
rac
tio
n
s
u
bst
a
tio
n.
T
he
i
n
v
e
r
te
r
is
c
o
u
p
le
d
to
a
n
i
nde
pe
n
d
en
t
trans
f
or
me
r
vi
a
an
L
CL
f
i
l
t
e
r
a
s
s
h
o
w
n
i
n
F
i
gure
1
(
b
).
B
o
t
h
re
cu
per
a
tin
g
inve
rters
a
p
ply
P
u
lse-
Wid
t
h-
Mo
du
la
ti
on
sw
it
c
h
i
n
g
sc
he
me
.
The
sw
i
t
c
h
in
g
fr
eq
ue
nc
y
ra
nge
s
fro
m
1
k
H
z
t
o
3
k
H
z
.
A
C
p
a
s
s
i
v
e
f
i
l
t
e
r
s
a
r
e
dem
a
nde
d
t
o
re
duce
the
l
i
n
e c
u
rre
nt
s
an
d v
o
l
t
a
g
es
d
i
s
t
o
rt
i
on.
+
_
DC
Tra
c
t
i
o
n
Lo
a
d
V
dc
AR
U
R
e
ct
i
f
i
e
r
T
r
an
s
f
o
r
m
e
r
T
r
a
c
tio
n
R
e
c
tif
ie
r
(
12-
pul
s
e
)
Fi
l
t
e
r
Th
r
e
e
-
p
h
a
s
e
In
v
e
rt
e
r
(a)
+
_
DC
Tr
a
c
t
i
o
n
Lo
a
d
V
dc
R
e
c
t
if
ie
r
T
r
a
n
s
f
o
r
me
r
T
r
a
c
tio
n
R
e
c
tif
ie
r
(1
2
-
p
u
l
s
e
)
Tr
a
n
s
f
o
r
m
e
r
D
C
P
o
w
e
r
R
e
ge
n
e
r
a
t
i
on
I
n
v
e
r
t
e
r
S
y
s
t
e
m
L
C
L
F
ilte
r
Th
r
e
e
-
p
h
a
s
e
I
nve
r
t
e
r
(b)
F
i
gure
1.
Recu
pe
rat
i
n
g
co
nve
rter
p
roposa
l
s for
the
t
r
act
i
on
pow
er
su
b
s
tatio
n
(TPSS),
(a)
Activ
e
r
eg
en
er
at
ion
Un
i
t
[
1
3
]
, (b
)
DC
p
o
w
er reg
e
n
er
at
io
n i
nver
t
er
syst
e
m
[15]
I
n
o
rder
t
o
mi
t
i
ga
te
t
he
h
arm
o
n
i
c
s
d
istor
t
i
o
n
w
i
tho
u
t
p
a
s
s
i
ve
f
i
l
ter
s
,
a
d
va
nce
d
m
u
l
t
ile
v
e
l
c
o
n
v
e
r
ter
has be
en
p
ro
po
se
d. F
igure
2 s
how
s the
pro
p
o
se
d co
nfi
gura
t
i
o
n o
f
a mu
l
t
i
le
vel c
o
nver
t
er
w
hic
h
use
d t
o
r
esto
r
e
the
re
ge
ner
a
t
i
ve
e
ne
rg
y
bac
k
t
o
t
h
e
uti
l
i
t
y
g
r
i
d
.
In
[
16]
,
a
17
-le
v
e
l
C
asc
a
de
d
H
-
Br
i
dge
(
CH
B)
c
onve
r
t
e
r
w
h
ic
h
is
m
od
u
l
ate
d
w
it
h
Le
v
e
l-S
h
ifte
d
P
u
l
s
e-Widt
h-M
o
du
l
a
t
i
on
(
L
S
-
P
W
M)
t
e
c
h
n
i
que
m
a
n
age
s
t
o
ke
ep
t
he
v
o
l
t
a
g
e
d
i
s
to
rtio
n
a
s
l
o
w
a
s
8%.
C
onv
erse
ly,
t
h
e
conf
ig
u
r
a
t
ion
o
f
t
h
e
powe
r
c
i
r
c
u
it
i
s
c
o
mp
l
e
x
by
i
n
v
o
l
vi
ng
appr
ox
im
ate
l
y
96
u
n
its
o
f
p
o
w
er
s
e
m
ic
o
n
d
u
c
t
or
s.
T
her
e
for
e
,
t
h
is
p
a
p
e
r
w
il
l
presen
t
a
com
p
ara
t
i
v
e
s
t
u
d
y
o
n
C
H
B
a
nd
Mo
du
lar
Mul
t
i
l
e
v
e
l
C
o
n
v
e
r
ter
(M
MC
)
.
T
he
a
i
m
i
s
to
d
e
t
er
m
i
n
e
t
he
m
ost
po
ten
t
ial
m
u
l
t
i
l
e
v
e
l
Evaluation Warning : The document was created with Spire.PDF for Python.
Int J
P
o
w
E
l
e
c
&
D
ri S
yst
IS
S
N
:
2088-
86
94
C
o
m
p
a
r
at
ive
st
udy
o
f
tw
o
po
te
nt
i
a
l
rec
upe
ra
t
i
n
g
c
onv
er
ters
in
D
C
ra
i
l
w
ay
ele
c
t
r
if
ica
t
io
n
(Z
. H. Cho
i
)
1
159
con
v
er
t
e
r
t
o
b
e
use
d
i
n
TP
S
S
w
hich
e
m
p
l
oys
l
esser
nu
m
b
er
o
f
p
o
w
e
r
s
em
i
c
on
duc
t
o
rs
w
hile
c
om
pl
y
w
i
t
h
harm
onic
d
is
tor
tion
index
set
by
I
EEE
S
t
andar
d
.
B
o
th
c
onver
t
ers
w
il
l
be
e
va
lu
a
t
e
d
u
s
i
n
g
i
d
e
nt
ica
l
modu
la
ti
o
n
t
e
c
hn
i
que,
i.e
.
L
S
-
P
W
M.
P
ure
si
nus
o
i
d
a
l
modu
la
ti
n
g
w
ave
s
w
i
ll
be
a
pp
l
i
ed
i
n
th
is
s
t
u
d
y
,
rec
upera
t
i
ng
i
n
ten
t
i
o
n
c
o
nt
r
o
l
te
c
h
n
i
que
a
n
d
pow
e
r
f
a
c
t
or
a
nal
y
sis
w
i
l
l
b
e
pre
s
e
n
te
d
i
n
our
n
ex
t
pa
pe
r.
T
hi
s
pape
r
is
o
u
t
l
i
ne
d
as
f
o
llow
s
.
The
oper
a
t
i
ona
l
pr
inc
i
ple
a
nd
LS
-
PWM
t
e
chn
i
qu
e
f
o
r
C
H
B
and
M
M
C
con
v
er
t
e
rs
a
r
e
b
riefl
y
r
e
v
i
e
w
e
d
in
S
e
c
t
i
on
2.
S
ec
tio
n
3
pre
s
e
n
t
s
s
i
m
u
la
ti
on
a
na
lysi
s
a
n
d
a
co
nc
l
u
s
i
on
w
i
l
l
b
e
prese
n
t
e
d i
n
S
ecti
o
n 4.
+
_
DC
Tra
c
t
i
o
n
Lo
a
d
V
dc
R
e
c
t
if
ie
r
T
r
a
n
s
f
o
r
me
r
T
r
a
c
ti
o
n
R
e
c
tif
ie
r
(1
2-
pul
s
e
)
M
u
lt
ile
v
e
l
C
o
n
v
e
r
t
e
r
F
i
gure
2.
P
rop
o
se
d m
u
lti
leve
l
conver
t
e
r
a
s recuper
a
tin
g
con
v
er
t
er
2.
MULT
I
L
E
V
EL CONVERTERS
Mu
l
t
i
le
ve
l
c
o
n
v
er
t
e
rs
a
re
c
o
m
m
only
u
s
ed
i
n
m
e
d
i
um
v
o
l
ta
ge
a
ppl
i
ca
ti
o
n
s
ra
te
d
fr
om
2
.3
k
V
–
6.6
kV
.
Class
i
c
m
u
lti
le
ve
l
co
n
v
erte
rs
i
nc
l
u
d
e
N
e
u
t
r
a
l
-P
oint-
C
lam
p
e
d
(
NP
C
)
,
F
l
y
i
ng
Cap
aci
to
r
(F
C
)
a
nd
C
a
sca
d
e
d
H
-B
rid
g
e
(CH
B
)
c
o
n
v
er
t
e
rs.
The
s
e
co
n
v
er
t
e
rs
h
ave
be
en
co
m
m
e
r
ci
al
i
zed
w
it
h
a
ma
xi
mu
m
ou
tp
ut
vo
lta
ge
l
e
v
e
l
r
ea
chi
ng
t
h
ree
,
f
our
a
nd
s
eve
n
t
e
e
n
l
e
v
e
l
s
respe
c
t
iv
e
l
y
.
A
d
v
a
n
ce
m
ul
tile
vel
c
o
n
v
e
r
ters
t
o
p
o
l
og
i
e
s
a
r
e
c
o
n
t
in
uou
sl
y
e
v
olv
e
d
b
a
s
e
d
on
t
h
e
se
c
l
a
ssi
c
al
c
o
nve
rter
s,
s
uch
as
H
-b
r
i
d
g
e
N
P
C
(H
N
P
C)
,
A
c
ti
ve
N
P
C
(
A
N
P
C),
Transit
o
r-C
lam
p
e
d
C
on
ve
rter
(
TCC),
M
o
du
lar
M
u
l
t
i
l
e
ve
l
Co
nve
r
t
er
(
MM
C
)
a
nd
hy
bri
d
m
ul
ti
le
vel
c
o
nver
t
e
r
s
[1
7-1
9
].
S
i
n
c
e
C
H
B
a
n
d
MMC
o
ffer
h
ig
h
m
o
du
l
a
ri
t
y
a
nd
fle
x
i
b
ilit
y
i
n
con
f
ig
ura
tio
n,
t
he
y
ar
e
se
lec
t
ed
i
n
th
is
c
o
m
pa
rati
ve
s
tudy.
I
n
ge
nera
l,
t
he
y
a
r
e
cla
s
sifie
d
a
s
m
u
lti-c
e
lls
con
v
er
ter.
T
he
y
em
plo
y
a
n
u
m
ber
of
p
ow
e
r
cells
w
hi
c
h
a
re
i
de
n
t
i
ca
l
in
d
esi
gn
us
in
g
l
o
w
ra
ti
n
g
c
om
p
one
n
t
s.
F
i
gure
3
prese
n
ts
t
he
p
ow
e
r
c
i
r
cu
it
s
a
n
d
p
o
w
er
c
ells
d
es
i
g
n
use
d
in
t
he
se
c
on
ve
rters.
T
he
n
um
ber
of
o
u
t
pu
t
vo
lta
ge l
eve
l
s,
m
, can be es
tim
a
ted w
i
th (
1).
2
1
(
1
)
Whe
r
e
N
i
s
t
h
e
n
u
m
b
er
o
f
t
o
ta
l
bri
d
ge
c
e
lls
c
on
fig
u
re
d
in
one
p
ha
se
l
e
g
of
C
H
B
o
r
t
h
e
num
ber
o
f
t
o
t
a
l
c
h
opp
e
r
c
el
l
s
co
n
fi
gu
re
d
in
o
ne
a
rm of MM
C.
The
c
o
mm
on
m
odu
l
a
tio
n
t
e
chn
i
que
s
us
ed
i
n
t
h
ese
c
o
n
v
er
t
e
rs
c
an
b
e
c
l
a
ssifie
d
a
s
car
rier-
b
ased
modu
la
ti
o
n
t
e
c
hn
i
que
s,
S
pac
e
-V
e
c
tor-Mo
d
u
l
a
t
i
o
n
(S
V
M
)
me
t
h
o
d
s,
a
n
d
S
el
ec
tiv
e
Harmo
n
i
c
El
imi
n
ati
on
(S
H
E
)
[16,
1
8
,
2
0]
.
Car
r
ier-
based
mo
d
u
la
t
i
on
i
s
s
i
mp
le
f
or
i
mp
l
em
en
ta
ti
o
n
b
ut
t
h
i
s
m
e
th
od
i
n
t
r
od
uc
e
hig
h
sw
it
c
h
i
n
g
l
o
sse
s.
W
her
eas,
the
c
o
mp
lex
i
t
y
o
f
t
h
e
S
V
M
a
l
gor
it
hm
incr
ea
se
s
exp
o
n
e
n
tia
ll
y
w
ith
t
he
i
nc
rea
s
i
n
g
numbe
r
of
p
o
w
e
r
c
e
l
ls
e
m
p
l
o
ye
d
.
T
here
fo
re,
this
p
a
p
er
c
ho
ose
t
o
e
va
lua
t
e
t
h
e
c
o
n
v
e
rte
r
s
us
in
g
L
e
vel-
S
h
ifte
d-
P
W
M
m
odu
la
tio
n.
T
hi
s
tec
h
ni
q
u
e
uses
i
de
n
tica
l
car
rier
w
a
v
e
f
o
r
mo
dul
ati
o
n
,
w
hi
c
h
i
s
h
i
gh
ly
su
i
t
a
b
le
f
or
F
P
G
A
im
pl
e
m
e
n
ta
tio
n
[2
1].
Th
e
ope
rat
i
o
n
p
ri
nci
p
le
a
n
d
Le
ve
l-Shifte
d-
PWM
sc
hem
e
s
o
f
C
H
B
and
M
M
C w
i
ll
be
s
u
m
m
a
riz
e
d in
t
he
fol
l
o
w
i
ng
s
u
b
-sec
ti
o
n
s
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SSN: 2088-
8694
Int J
P
o
w
El
e
c
&
D
ri S
yst
,
V
ol.
10,
N
o.
3
, S
e
p
2
0
1
9
:
115
7
– 1
166
1
160
C
S1
S1
'
(d)
C
hopp
e
r
C
e
l
l
(C
C
)
+
_
v
c
+
_
v
CC
BC
aN
BC
bN
BC
c2
BC
c1
BC
cN
n
ab
c
(a) C
H
B
BC
b2
BC
b1
BC
a2
BC
a1
+
_
1
a
BC
v
+
_
2
a
BC
v
+
_
an
BC
v
C
S2
S2'
S1
S1
'
(c)
B
r
i
dge
C
el
l
(B
C
)
+
_
v
c
+
_
v
BC
CC
al
1
CC
al
N
CC
bl
1
CC
bl
N
CC
cl
1
CC
cl
N
(
b
)
M
M
C
CC
au
N
CC
au
1
CC
bu
N
CC
bu
1
CC
cu
N
CC
cu
1
a
b
c
+
_
o
2
dc
V
+
_
2
dc
V
w
x
y
z
L
ar
m
L
ar
m
v
L
_
+
_
+
v
L
i
a
i
la
i
ua
Up
p
e
r
ar
m
Lo
w
e
r
ar
m
F
i
gure
3.
P
ow
er c
ircuit
o
f
(
a) c
asca
de
d h-
bridge
c
o
nve
rter
(
CH
B
),
(
b)
m
odular
m
ulti
le
vel
c
o
n
v
erter
(MM
C
),
(c) bridge
cell
(
B
C),
and
(d)
c
h
opper
c
el
l
(CC)
2.1.
Cascad
ed
H-bridge
con
v
ert
er
(CHB)
Casc
a
d
ed
H
-
B
rid
g
e
(CH
B
)
con
v
erte
r
is
c
o
n
f
i
g
ured
b
y
a
numbe
r
of
b
r
i
dge
c
e
l
l
s
c
onn
e
c
te
d
in
s
e
r
i
e
s
p
e
r ph
a
s
e
l
e
g
a
s
s
ho
wn
i
n
F
i
gu
re
3
(a
).
A
u
nit
o
f
Bri
dg
e
C
e
l
l
(B
C) em
p
lo
ys four
uni
ts of
pow
er
sem
ic
on
duc
t
o
r
(S
1, S
1’,
S
2
, a
nd S
2
’) and a c
a
pa
ci
tor
,
C
.
The ca
paci
tanc
e o
f
e
ach bri
d
g
e c
e
ll is i
den
t
ica
l
to
form
a sy
mm
etric
C
H
B
.
T
h
e
p
owe
r
s
e
m
i
c
o
ndu
c
t
o
r
s
a
r
e
swit
chi
n
g
in
p
ai
r
t
o
g
en
era
t
e
t
hr
ee
v
o
l
t
a
g
e
l
e
v
e
ls
(
v
c
,
0
,
-
v
c
)
at
t
h
e
bri
dge
c
e
l
l
t
e
r
m
i
n
a
l
,
v
BC.
E
a
c
h
pha
se out
pu
t
vo
l
t
age
,
v
pn
,
c
a
n
be determ
i
ne
d
by
sum
m
i
ng
up
a
l
l
v
o
l
t
a
g
e val
u
es
gi
ve
n by
the
br
id
ge
cel
ls,
w
h
ic
h a
r
e
connec
t
e
d
in t
h
e
sam
e
ph
a
s
e leg.
v
pn
∑
(
2
)
Whe
r
e
N
i
s
t
h
e
n
u
m
b
er
o
f
t
o
t
a
l
bri
d
ge
c
e
l
ls
c
on
figur
ed
i
n
one
pha
se
l
e
g
a
nd
p
r
epres
e
nts
phases
a
-b-
c
.
In
order
to o
bta
i
n ba
la
nce
t
h
ree
-
p
h
ase
A
C
vo
l
t
a
ges,
a
ll p
h
ase
l
e
gs
sh
o
u
l
d c
o
n
s
is
t equa
l
n
u
mbe
r
s of bri
dge
cell
s
.
T
o
i
m
plem
en
t
Leve
l
S
h
i
f
t
e
d
-
P
W
M
(
L
S
-
P
W
M)
m
e
t
ho
d,
t
hree
s
i
n
us
o
i
d
a
l
w
a
v
e
s
w
i
t
h
1
2
0
pha
se
sh
i
f
t
are
used
a
s
t
h
e
m
o
d
u
l
a
ti
ng s
i
g
n
a
l
s for e
ach
pha
se.
These
sig
n
al
s ar
e form
ul
a
t
ed a
s fol
l
o
ws:
v
mo
d_
a
sin
2
v
mo
d_
b
sin
2
(
3
)
v
mo
d_
c
sin
2
2
3
Whe
r
e
V
m
re
pr
esen
ts
t
he
p
ea
k
am
p
lit
ude
a
n
d
f
m
r
e
f
er
s
to
t
he
fre
que
nc
y
o
f
m
od
u
l
a
t
ing
w
a
ve.
I
n
a
dd
i
t
i
on,
2
N
un
its
o
f
car
rier
w
a
v
es
a
re
d
e
m
ande
d
to
c
o
n
t
ro
l
N
u
n
i
t
s
o
f
b
r
i
d
g
e
cel
ls
p
e
r
p
h
a
se
.
Th
e
s
e
ca
rri
e
r
wa
v
e
s
are
ide
n
ti
c
a
l,
a
b
a
s
i
c
c
arr
i
e
r
w
ave,
v
,
can
b
e
expre
s
se
d b
y
the
f
o
l
l
o
w
i
ng
eq
ua
ti
o
n
.
v
,
0
,
(
4
)
Whe
r
e
N
i
s
t
h
e
n
u
m
b
er
o
f
t
o
ta
l
bri
d
ge
c
e
lls
c
on
fig
u
re
d
in
one
p
ha
se
l
e
g
a
n
d
f
c
d
e
n
o
t
e
s
t
h
e
car
rier
w
a
v
e
fre
que
nc
y.
T
hi
s
ba
si
c
ca
rrier
w
ave
i
s
t
hen
d
u
p
l
icat
ed
a
n
d
s
hif
t
e
d
a
c
c
o
rdi
n
gly
f
o
r
m
odula
t
i
o
n.
T
he
c
o
n
v
e
r
t
e
r
em
plo
y
s
four
u
ni
t
s
o
f
bri
d
ge
c
ell
p
e
r
p
h
ase.
E
a
c
h
bri
dge
c
e
ll
w
ill
be
c
on
t
r
olle
d
by
t
w
o
u
n
i
t
s
of
car
rier
w
a
v
e
s
,
nam
e
ly
v
a
nd
v
.
Evaluation Warning : The document was created with Spire.PDF for Python.
Int J
P
o
w
E
l
e
c
&
D
ri S
yst
IS
S
N
:
2088-
86
94
C
o
m
p
a
r
at
ive
st
udy
o
f
tw
o
po
te
nt
i
a
l
rec
upe
ra
t
i
n
g
c
onv
er
ters
in
D
C
ra
i
l
w
ay
ele
c
t
r
if
ica
t
io
n
(Z
. H. Cho
i
)
1
161
v
v
1
(
5
)
v
v
(
6
)
The
p
o
wer
swi
t
c
h
e
s
in e
ach
b
rid
g
e c
e
ll a
r
e
con
t
ro
l
l
e
d
bas
e
d
on
the
fo
ll
ow
ing
co
n
d
i
tio
ns
:
S1
o
f
BC
pi
is trig
g
ere
d
ON
when
_
(
7
)
S2
o
f
BC
pi
is trig
g
ere
d
ON
when
_
(
8
)
Whe
r
e
p
r
e
p
rese
n
t
s
pha
se-a
,
p
h
ase-
b
or
p
hase-c
.
Whe
n
S
1
an
d
S
2
’
ar
e
tr
i
g
ger
e
d
on
,
a
br
idge
c
e
l
l
w
ill
c
o
nt
ribu
t
e
a
c
ap
ac
ito
r
vol
t
a
g
e
,
v
c
,
to
t
he
o
ut
p
u
t
p
h
ase
v
o
l
t
a
g
e.
I
nversel
y
b
y
t
u
rni
n
g
on
S
1
’
an
d
S
2
s
w
i
t
c
h
e
s
,
a
nega
t
i
ve
c
a
p
ac
it
or
v
o
l
t
a
ge,
v
c
,
w
ill
b
e
pres
ente
d.
Z
ero
v
o
l
t
a
ge
l
e
v
e
l
w
i
l
l
be
a
c
h
ieve
d
b
y
s
e
t
t
i
n
g
(
S
1
a
n
d
S
2
)
or (S
1
’
and
S
2
’)
at
active
st
a
t
u
s
.
2.2.
Mod
u
lar
multi
l
e
v
e
l
c
on
vert
er
(MM
C
)
Th
e
p
o
w
e
r
c
i
r
c
u
it
o
f
M
odu
la
r
M
u
lt
il
ev
el
C
o
n
v
e
rt
e
r
(
M
M
C
)
s
ho
wn
i
n
F
i
gur
e
3
(b)
ill
u
strat
e
s
that
ea
ch
pha
se
l
eg
c
o
n
s
i
st
s
of
t
w
o
a
rm
s
whe
r
e
a
n
u
m
b
er
o
f
c
h
op
per
c
el
l
s
a
re
c
o
n
n
ect
ed
i
n
se
ri
e
s
.
Th
e
nu
mb
e
r
o
f
c
h
o
p
p
e
r
c
e
l
l
m
u
s
t
b
e
e
q
u
i
v
a
l
e
n
t
i
n
e
a
c
h
a
r
m
t
o
e
n
s
u
r
e
a
s
y
m
m
e
t
r
y
A
C
v
o
l
t
a
ge
w
a
v
efor
m
w
ill
be
p
rod
u
ce
d.
A
n
a
r
m
i
n
d
u
c
t
o
r
,
L
arm
,
i
n
se
r
t
ed
n
ear
t
he
A
C
te
rm
i
n
a
l
a
r
e
m
a
i
nly
em
p
l
oye
d
to
s
u
ppress
t
he
c
ircu
la
t
i
n
g
c
urrent
and
l
i
m
it
t
h
e
A
C
c
urr
e
nt
a
r
i
si
ng
r
a
te
w
he
n
fa
u
l
t
c
u
r
r
ent
i
s
l
oc
a
t
e
d
w
ith
i
n
t
he
M
M
C
[
22].
A
c
hoppe
r
ce
l
l
c
o
nt
ai
ns
a
c
a
p
aci
t
o
r,
C
,
a
nd
t
w
o
u
n
i
t
s
o
f
p
o
w
er
s
w
itch,
S1
and
S1
’
.
Thes
e
com
p
o
n
en
ts
a
re
c
onfig
ure
d
i
n
ha
l
f
-
bri
dge
c
o
n
fig
u
r
a
ti
on
as
s
h
o
w
n
i
n
F
i
gure
3(
d).
P
o
w
e
r
sw
itches
a
r
e
tri
gge
red
com
p
l
e
me
nt
a
r
y
t
o
p
ro
du
c
e
t
w
o
vo
lta
ge
l
e
v
e
l
s
(
e
i
t
he
r
0
V
or
v
c
V
)
at
t
h
e
c
hopp
e
r
c
el
l
t
e
rmi
n
al
,
v
CC
.
Thus,
t
h
e
ar
m
v
o
lta
ge
s,
v
wx
a
n
d
v
yz
,
c
a
n be
expre
s
se
d a
s
f
o
l
l
o
w
s
:
v
wx
∑
(
9
)
v
yz
∑
(
10)
Whe
r
e
N
i
s
th
e
n
u
mbe
r
o
f
tota
l
ch
o
pper
c
e
lls
c
on
fig
u
re
d
i
n
one
a
rm
a
nd
p
r
epresents
phase-a,
phase-b
or
pha
se-
c
.
The
pos
iti
tve
dire
ct
ion
of
t
he
u
p
p
e
r
a
nd
low
e
r
arm
cur
rent
f
or
pha
se-
a
,
i
ua
a
nd
i
la
,
are
il
lu
str
a
ted
in
F
i
gure
3 (
b
).
T
hese
c
urr
e
nts for
m
t
he
A
C c
u
rre
nt
a
s follow
s
:
i
p
(
11)
Whe
r
e
p
re
p
resent
s pha
se-a
, pha
se-b
o
r pha
se
-c. The
pol
e
v
o
l
t
a
g
e
,
v
ao
,
c
a
n be
der
iv
e
d
a
s
fol
l
ow
s:
v
ao
=
=
(
12)
To
i
m
p
l
e
me
n
t
L
evel
S
h
i
fted
-P
WM
(
LS-P
WM)
me
t
h
o
d
i
n
MMC,
six
modu
la
ti
n
g
s
i
g
na
ls
a
nd
N
u
n
i
t
s
o
f
ca
rrier
w
aves
a
r
e
d
em
ande
d.
T
he
u
p
p
er
a
rm
a
nd
l
o
wer
a
r
m
m
odu
la
t
i
ng
sig
n
a
l
s
a
re
s
hi
ft
ed
180
a
p
a
r
t
,
a
s
gi
ve
n be
low
s
:
v
mo
d_
a
u
sin
2
v
mo
d_
a
l
sin
2
v
mo
d_
b
u
sin
2
v
mo
d_
b
l
sin
2
(
13)
v
mo
d_
c
u
si
n
2
v
mo
d_
c
l
sin
2
Whe
r
e
V
m
an
d
f
m
r
epre
se
n
t
s
t
h
e
pe
ak
a
m
p
l
i
t
ude
a
n
d
f
r
e
qu
enc
y
o
f
mod
u
l
ati
n
g
w
a
ve
.
N
numbe
r
o
f
i
de
nt
ica
l
ca
rrier
w
a
v
es
a
re
d
em
ande
d
to
c
on
tro
l
N
u
nits
o
f
c
h
op
pe
r
c
e
lls
l
oca
t
e
d
i
n
e
ach
a
r
m
o
f
the
MM
C
.
A
b
as
ic
carrier
w
ave for MMC
,
v
,
is formulate
d
as fo
l
l
o
w
s
:
v
1
,
0
1
,
(
14)
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SSN: 2088-
8694
Int J
P
o
w
El
e
c
&
D
ri S
yst
,
V
ol.
10,
N
o.
3
, S
e
p
2
0
1
9
:
115
7
– 1
166
1
162
Whe
r
e
N
i
s
t
h
e
n
u
mbe
r
o
f
to
t
a
l
c
h
op
p
e
r
ce
ll
s
c
o
n
f
ig
u
r
e
d
i
n
one
a
r
m
a
nd
f
c
d
e
n
o
t
e
s
t
h
e
c
a
r
r
i
e
r
w
a
v
e
fre
que
nc
y.
T
h
i
s
bas
i
c
c
a
rr
ier
w
a
ve
i
s
the
n
d
up
l
i
c
a
t
e
d
an
d
shi
f
t
ed
v
ert
i
call
y
f
o
r
m
odu
l
a
t
i
o
n
.
E
ach
c
ho
pp
e
r
c
el
l
w
ill
be c
on
t
r
o
l
l
e
d
by
v
a
s formul
a
t
e
d
in
the
fo
ll
o
w
in
g
equa
t
i
on.
v
v
(
15)
The
sw
i
t
c
h
in
g c
o
n
d
i
t
i
on o
f
p
o
w
er
s
w
i
t
c
h,
S
1,
i
n ea
ch
c
hop
p
e
r
ce
l
l
i
s
sum
m
ariz
ed a
s:
S1
o
f
CC
pui
i
s
t
rigge
red
O
N
when
_
(
16)
S1
o
f
CC
pli
is trig
g
er
ed O
N whe
n
_
(
17)
Whe
n
s
w
i
t
c
h S
1
is tri
ggere
d o
n
,
the c
a
pac
itor
vol
t
a
ge,
v
c
, w
i
ll be
p
rese
nt
e
d
a
t the
ch
o
p
p
e
r
c
e
ll t
e
rm
inal.
I
n
s
umm
a
ry,
the
CH
B
ou
tp
u
t
v
o
l
t
a
ge
w
a
v
e
f
or
m,
v
an
,
an
d
t
h
e
po
le
vol
t
a
ge
w
a
v
e
f
o
r
m,
v
ao
,
o
f
MMC
are
presen
te
d
si
de
b
y
s
i
de
i
n
F
i
gure
4.
I
t
is
c
lear
ly
s
h
o
w
n
tha
t
M
M
C
p
ro
d
u
ce
s
a
m
o
re
s
i
n
us
oida
l
vo
l
t
ag
e
w
a
ve
form
w
i
t
h
sma
lle
r
am
plit
ude.
The
ma
gn
itu
de
o
f
th
e
ou
t
p
u
t
v
o
l
t
a
g
e
w
a
ve
form
c
an
b
e
t
une
d
us
i
n
g
am
plit
ud
e
m
odula
t
i
o
n
rat
i
o,
m
a
,
fo
r
bot
h
con
v
er
t
e
rs.
For
l
i
nea
r
m
od
ula
t
ion,
t
he
p
e
a
k
v
o
lta
ge
of
t
he
modu
la
ti
n
g
w
a
v
e
i
s
lim
it
e
d
t
o
m
a
ximum
of 1
[
p.u.
] a
s
give
n
in
(
18).
m
a
(
18)
Whe
r
e
V
m
repr
esen
ts the
p
ea
k
am
pl
it
u
d
e
of
m
odu
la
tin
g
w
a
ve
.
(a)
(b)
F
i
gure
4. P
hase-
a
o
ut
pu
t v
o
l
t
age
w
a
ve
form
s of
(
a) CH
B
a
n
d
(
b) M
MC
3.
SIMU
L
A
TION
V
ERIFIC
AT
ION
Tw
o
trac
ti
on
sub
s
ta
t
i
on
mo
de
ls
a
s
i
llus
t
ra
t
e
d
i
n
F
i
g
ure
2
are
c
ons
truc
te
d
w
ith
t
he
m
ain
a
i
m
to
com
p
are
the
pe
rfor
ma
nce
o
f
C
H
B
a
n
d
M
M
C
a
s
r
e
c
upe
rat
i
ng
c
o
nver
t
e
r.
T
hese
s
im
u
l
a
t
i
on
m
o
d
e
ls
u
se
d
a
9
0
0
V
cons
ta
nt
d
c
sour
ce
vo
l
t
a
g
e
to
r
e
p
re
se
n
t
t
h
e
a
c
h
ie
va
b
l
e
m
a
ximu
m
rege
n
e
ra
t
i
ve
b
r
a
ki
ng
v
o
l
tage,
V
dc
[
23]
.
In
add
i
tio
n,
t
he
A
C
gri
d
a
nd
r
ec
tifie
r
t
r
a
n
sform
e
r
a
r
e
m
odele
d
as
RL
-loa
d
c
o
nfi
gured
i
n
Y
-
c
on
nec
t
i
o
n.
T
he
l
oa
d
para
me
ters
a
re fi
x
e
d
a
c
c
ord
i
n
g
to [
1
6
]
.
Table
1 pre
s
e
n
ts
t
he
si
mula
t
i
o
n
pa
r
am
eter
s.
0.
05
0.
06
0.
07
0.
08
0.
09
0.
1
-4
-2
0
2
4
v
an
[
pu]
ti
m
e
(
s
)
0.
0
5
0.
06
0.
0
7
0.
08
0.
0
9
0.
1
-4
-2
0
2
4
v
ao
[p
u
]
ti
m
e
(
s
)
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t
J
P
o
w
Elec
&
D
r
i
S
y
st
I
S
S
N
:
2088-
86
94
Com
p
a
r
a
t
i
v
e
st
udy
o
f
t
w
o
po
t
e
nti
a
l re
c
uper
a
t
i
ng
co
nve
r
t
e
rs in D
C
ra
i
l
w
ay
elec
t
r
i
f
i
ca
t
i
o
n
(
Z
. H
.
Cho
i
)
1
163
Ta
ble
1.
S
i
m
u
latio
n
par
a
me
ter
s
C
a
s
c
a
d
e
d
H
-
B
r
idge
C
onv
e
r
t
e
r
Modul
a
r
M
ultil
e
v
el
C
onve
rt
e
r
N
u
m
b
e
r
o
f
powe
r
c
e
l
l
p
e
r
pha
s
e
,
N
4
8
Ca
p
a
c
itor volta
g
e
l
e
v
e
l
p
e
r
powe
r
c
e
ll,
V
c
225
V
225
V
A
r
m
induc
tor,
L
ar
m
NA
60
µ
H
R
e
sist
iv
e
L
o
a
d
p
e
r
pha
s
e
,
R
0
.3
Ω
0
.3
Ω
I
n
du
ct
iv
e
Lo
ad
p
e
r
p
h
a
s
e
,
L
50
µH
50
µH
F
r
e
que
n
c
y
Modu
l
a
ti
on
I
n
d
e
x
,
m
f
2
1
21
Am
plit
ude
M
odula
tion
Inde
x,
m
a
0
.
545
1
Am
plit
ude
r
a
tio
o
f
tria
ngul
a
r
w
a
v
e
s
,
0.
2
5
0
.
5
The
f
i
r
s
t
s
i
mu
l
a
ti
o
n
m
o
d
e
l
i
m
p
lem
e
n
t
s
a
t
h
ree
-
phase
C
H
B
a
s
t
h
e
r
ecu
p
e
r
a
ti
ng
c
o
nver
t
e
r
.
The
C
H
B
c
o
n
s
is
ts
o
f
f
o
u
r
b
r
i
dge
c
e
l
ls
i
n
eac
h
pha
se
.
F
our
u
n
i
t
s
o
f
ide
a
l
I
G
B
T
p
o
w
er
s
w
itches
a
r
e
used
t
o
f
o
r
m
t
he
br
idge
c
el
l
.
T
he
c
apa
c
i
t
o
r
of
e
ach
b
r
i
dge
c
e
l
l
i
s
m
ode
lle
d
a
s
a
c
on
sta
n
t
volta
ge
s
o
u
r
c
e.
T
he
d
c
s
o
ur
ce
i
s
set
t
o
22
5
V
w
i
t
h
t
he
a
ssump
t
i
o
n
t
h
a
t
the
br
id
ge
c
ell
s
i
n
o
n
e
pha
se
l
e
g
e
qua
l
l
y
div
i
de
d
t
h
e
V
dc
.
F
i
gur
e
5
(
a
)
show
s
the
m
o
d
u
la
t
i
on
a
nd
car
rier
w
aves
o
f
LS
-P
WM
i
n
CHB.
E
i
g
h
t
u
n
its
o
f
i
d
e
n
t
i
c
a
l
c
a
r
r
i
e
r
w
a
v
e
s
a
r
e
e
m
p
l
o
y
e
d
.
The
s
e
ca
rrier
w
ave
s
a
re
s
et
t
o
1
0
50
Hz
w
ith
a
n
am
pl
itu
de
o
f
0.2
5
V
e
a
c
h
.
Thr
e
e
u
n
i
t
s
o
f
50
H
z
m
od
ul
a
tin
g
w
a
ves
a
r
e
use
d
a
s
t
h
e
r
e
fer
e
nce
s
i
gna
ls
f
or
m
od
ul
a
tio
n.
T
he
a
mp
li
tude
o
f
t
h
e
m
o
d
u
la
t
i
ng
w
a
v
e,
V
m
i
s
s
e
t
t
o
0.
54
5
V
w
i
th
t
he
a
im
t
o
ens
u
r
e
t
h
a
t
t
h
e
ef
f
e
c
t
i
v
e
va
lu
e
of
t
h
e
o
u
tpu
t
lin
e
-
lin
e
v
o
l
t
a
g
e
s wi
ll
re
a
c
h
5
85
V [
9
]
.
T
h
e
se
co
nd
s
i
m
u
l
a
tio
n
m
o
de
l
emp
l
oy
s
a
t
h
ree
-
ph
a
s
e
MMC
a
s
t
h
e
re
cupe
r
a
ti
n
g
c
on
ve
r
t
er
.
This
c
o
n
v
er
ter
i
s
m
ode
le
d
w
i
th
f
o
u
r
un
i
t
s
o
f
c
h
o
pper
c
e
l
l
p
e
r
a
r
m
.
E
ach
c
ho
p
p
er
c
ell
is
m
o
d
e
l
l
e
d
usi
n
g
tw
o
u
n
its
of
i
dea
l
I
G
B
T pow
er
s
w
itc
h
a
nd
a
f
i
xe
d
dc
s
our
ce
i
s
use
d
t
o
r
e
p
r
e
sen
t
t
he
c
a
p
ac
it
or
v
o
l
t
a
ge.
I
t
i
s
d
o
c
u
m
e
nted
t
h
at
a
t
ev
e
r
y
inst
a
n
t
,
h
alf
n
u
m
b
e
r
s
of
c
ho
pp
e
r
c
e
l
l
int
e
g
r
a
t
ed
wi
th
in
o
n
e
-ph
a
se
l
eg
w
il
l
be
a
c
t
i
v
at
ed
,
th
ere
f
o
r
e
t
h
e
cap
a
c
i
t
o
r
v
o
l
t
a
g
e
o
f
ea
ch
c
h
opp
er
c
e
l
l
i
s
s
e
t
t
o
22
5
V
(
V
dc
/
4
)
.
T
h
e
a
r
m
i
n
d
u
c
t
a
n
c
e
i
s
s
e
t
t
o
6
0
µ
H
i
n
t
h
i
s
sim
u
la
ti
on.
T
h
e
L
S
-
P
W
M
te
c
h
n
i
que
u
se
d
i
n
M
MC
j
u
s
t
r
e
q
u
ir
e
s
f
our
i
dent
i
cal
c
a
r
ri
er
w
a
v
es
w
i
t
h
six
uni
ts
o
f
m
odu
la
tin
g
w
a
ves.
T
he
s
w
itc
hi
n
g
f
r
e
que
nc
y
of
t
he
car
r
i
er
w
a
v
e
i
s
se
t
t
o
1
050
H
z
an
d
th
e
ampl
itu
d
e
o
f
e
ach
c
a
r
r
i
e
r
w
a
ve
i
s
se
t
to
0
.
5
V
.
The
am
pl
it
u
d
e
of
m
o
d
u
l
a
tin
g
w
a
ves
a
r
e
s
et
t
o
a
ma
x
i
m
u
m
of
1
V
(
li
nea
r
m
odu
la
tio
n)
.
F
i
g
u
r
e
5
(
b)
a
nd
(
c
)
c
l
e
a
r
l
y
i
l
lu
st
r
a
te
a
l
l
t
he
m
o
dulatio
n
s
i
gn
a
l
s
u
s
ed
fo
r
LS
-
P
W
M in
MMC.
(a)
(b
)
(c)
F
i
g
u
r
e
5:
L
S-P
W
M
f
o
r
(a) CHB
with
m
a
=
0
.
5
4
5
,
(
b
)
uppe
r
a
r
m
M
M
C
w
ith
m
a
= 1
.0
,
an
d
(c)
lo
wer ar
m
MM
C
wit
h
m
a
=
1
.
0
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SSN: 2088-
8694
Int J
P
o
w
El
e
c
&
D
ri S
yst
,
V
ol.
10,
N
o.
3
, S
e
p
2
0
1
9
:
115
7
– 1
166
1
164
F
i
gure
6
s
h
ow
s
the
s
i
mu
la
ti
o
n
r
e
s
u
lts
o
f
curr
ent
s
a
nd
vol
ta
ge
s
w
a
v
e
form
s
for
tw
o
pro
pose
d
rec
upera
t
i
ng
c
o
n
v
e
r
ters.
CH
B
co
n
v
erter
results
a
re
t
abulated
i
n
c
o
l
u
m
n
(
a
)
w
h
i
l
e
M
M
C
r
e
s
u
l
t
s
a
r
e
s
h
o
w
n
i
n
col
u
m
n
(
b
)
.
A
ll
v
o
l
t
a
g
es
a
nd
c
ur
rents
w
a
ve
form
s
a
r
e
bala
nc
e.
F
i
gure
6
(a)
i.
d
e
p
i
c
t
s
t
hree
p
ha
se-v
ol
tage
s
w
a
ve
form
s
gener
a
te
d
by
CH
B.
S
ince
t
he
a
m
p
l
i
t
ude
m
od
ula
t
i
o
n
i
n
de
x,
m
a
i
s
se
t
t
o
0
.54
5
,
onl
y
t
h
ree
u
n
its
o
f
bri
dge
c
e
ll
(
p
e
r
phase)
a
r
e
a
c
t
i
v
e
l
y
trig
ger
e
d.
T
he
ref
o
re,
se
ve
n-
leve
l
o
u
t
p
u
t
p
ha
se-v
ol
ta
ges
ar
e
o
b
t
a
i
n
e
d
w
i
t
h
the
v
o
l
t
a
g
e
harm
onic
d
i
s
t
or
tion
(
TH
D
v
)
is
m
ea
su
r
e
d
at
2
5.06
%.
O
n
t
h
e
ot
her
ha
n
d
,
al
l
t
h
e
c
h
op
per
ce
l
ls
i
n
M
M
C
a
r
e
be
ing
a
c
t
i
v
e
l
y
sw
i
t
c
h
e
d
t
o
pro
d
u
ce
a
ni
ne-le
v
e
l
out
pu
t
pha
s
e
-
volta
ge
s
(F
i
gure
6
(b)
i.
).
T
hese
vo
lta
ge
s
a
r
e
more
s
i
n
us
o
i
da
l.
T
he
v
o
l
ta
ge
h
a
r
m
o
nic
d
i
stor
ti
o
n
(
TH
D
v
)
i
s
m
e
a
sure
d
ar
oun
d
8%.
F
i
gur
e
6
i
i
.
and
i
i
i
.
i
l
l
us
tr
ate
a
l
l
line
-
l
i
n
e
v
ol
t
a
ges
ge
n
e
rated
b
y
(
a)
C
H
B
a
n
d
(
b
)
M
M
C
.
C
H
B
p
r
o
d
u
c
e
s
a
n
i
n
e
-
l
e
v
e
l
vo
lta
ge
w
a
v
e
f
orm
s
w
it
h
the
e
ffe
c
t
i
v
e
fu
nda
m
e
nta
l
l
ine-
li
n
e
v
o
l
t
age
doc
u
m
ente
d
a
t
5
85.
1
V
and
TH
D
v
e
q
u
a
l
to
1
6.27%
.
M
M
C
ge
ne
rat
e
s
a
mor
e
s
inus
o
i
da
l
l
i
ne
-
l
i
n
e
vo
l
t
age
w
a
ve
form
s,
how
ever
t
he
e
ffec
ti
ve
f
und
a
m
e
n
t
a
l
l
i
n
e
-li
n
e
vo
lt
ag
e
i
s
c
a
p
t
u
red
a
t
5
46
.3
V
.
Al
t
h
o
ugh
,
t
he
r
m
s
v
al
ue
o
f
the
l
i
n
e-l
i
ne
v
olta
ge
s
a
r
e
a
b
out
6
.6
%
l
e
ss
t
h
a
n
t
h
e
d
e
m
a
n
d
e
d
585
V
,
th
e
vo
l
t
a
g
e
h
armo
n
i
c
d
is
tor
tio
n is c
om
pl
ied
w
ith the
8%
i
n
dustri
a
l
st
a
ndard.
La
st
l
y
,
th
r
ee
pha
se-
c
urr
e
nts
w
a
ve
form
s
ar
e
gi
ve
n
i
n
F
i
g
u
r
e
6
i
v
.
CHB
p
r
oduc
es
a
m
o
r
e
d
i
st
o
r
t
e
d
curr
ent
wa
ve
for
m
s
(
THD
i
=
1
3.8
3
%)
c
o
m
pare
t
o
M
M
C
.
G
ood
q
u
a
li
ty
c
urr
e
n
t
w
a
v
es
w
it
h
t
h
e
THD
i
appr
ox
im
ate
l
y
3%
i
s
g
i
ve
n
by
M
M
C.
T
a
b
le
2
t
ab
u
l
at
es
t
he
TH
D
i
nde
xe
s
pr
o
d
u
c
ed
b
y
tw
o
pr
op
os
e
d
con
v
er
t
e
rs.
Ba
se
d
o
n
t
he
v
o
lta
ge
a
nd
c
u
r
r
ent
w
a
v
e
form
s
qua
l
i
t
y
,
M
M
C
i
s
c
o
nc
lu
d
e
d
a
s
t
he
p
o
t
e
n
tia
l
rec
upera
t
i
ng
c
o
n
v
erte
r for future DC r
a
ilw
ay e
lectr
i
fic
a
tio
n
sy
st
e
m
.
(a)
(b)
F
i
gure
6
:
S
i
m
ulat
i
o
n
re
su
l
t
s o
f
(
a) CH
B
a
nd
(b) MMC.
The
sub-p
l
ots show: i.
phase
v
oltages waveform
s,
(
v
an
,
v
bn
,
v
cn
), ii
.
l
i
n
e
-
l
i
ne
v
o
lta
ges
w
a
vef
o
rms
(
v
ab
,
v
bc
,
v
ca
),
i
ii.
line
-
l
i
ne
vo
l
tage
s
w
a
vefor
m
s (
v
cb
,
v
ac
,
v
ba
),
i
v.
pha
se
c
urre
nt
s
w
a
ve
form
s (
i
a
,
i
b
,
i
c
).
Tab
l
e 2.
Tota
l
h
arm
o
n
i
c
dis
t
or
t
i
on
in
de
xes c
o
m
p
ar
i
s
on
be
t
w
een
t
wo
p
ot
en
ti
al
rec
u
p
e
ra
tin
g
c
onv
e
r
t
e
rs.
C
a
s
cad
ed
H-
B
r
i
d
g
e
C
onve
rt
e
r
(
C
H
B
)
Modula
r
Multile
v
e
l
C
onve
rt
e
r
(
M
M
C
)
Pha
s
e
volta
g
e
distorti
on,
TH
D
v
25.
06
%
7.
99
%
L
i
ne
-lin
e
volt
a
ge
distorti
on,
TH
D
v
16.
27
%
7.
99
%
P
h
as
e
cu
r
r
e
n
t
distorti
on,
TH
D
i
13.
83
%
2.
98
%
0.
96
0.
9
6
5
0.
97
0.
9
7
5
0.
98
0.
985
0.
99
0.
995
1
-
500
0
500
0.
96
0.
9
6
5
0.
97
0.
9
7
5
0.
98
0.
985
0.
99
0.
995
1
-
1000
0
1000
0.
96
0.
9
6
5
0.
97
0.
9
7
5
0.
98
0.
985
0.
99
0.
995
1
-
1000
0
1000
0.
96
0.
9
6
5
0.
97
0.
9
7
5
0.
98
0.
985
0.
99
0.
995
1
-
2000
0
2000
ti
m
e
(
s
)
0.
96
0.
96
5
0.
97
0.
97
5
0.
98
0.
9
8
5
0.
9
9
0.
995
1
-50
0
0
50
0
0.
96
0.
96
5
0.
97
0.
97
5
0.
98
0.
9
8
5
0.
9
9
0.
995
1
-100
0
0
100
0
0.
96
0.
96
5
0.
97
0.
97
5
0.
98
0.
9
8
5
0.
9
9
0.
995
1
-100
0
0
100
0
0.
96
0.
96
5
0.
97
0.
97
5
0.
98
0.
9
8
5
0.
9
9
0.
995
1
-200
0
0
200
0
ti
m
e
(
s
)
i.
ii
.
i
ii.
iv
.
Evaluation Warning : The document was created with Spire.PDF for Python.
Int J
P
o
w
E
l
e
c
&
D
ri S
yst
IS
S
N
:
2088-
86
94
C
o
m
p
a
r
at
ive
st
udy
o
f
tw
o
po
te
nt
i
a
l
rec
upe
ra
t
i
n
g
c
onv
er
ters
in
D
C
ra
i
l
w
ay
ele
c
t
r
if
ica
t
io
n
(Z
. H. Cho
i
)
1
165
4.
CONCL
U
S
ION
The
rege
nera
ti
ve
b
r
a
k
i
ng
e
n
e
r
gy
o
f
L
ig
h
t
-R
ail-Tra
n
s
i
t
(LR
T
)
veh
i
c
l
e
can
b
e
t
r
ans
f
e
r
re
d
b
a
ck
t
o
th
e
ac
gri
d us
in
g r
ecupe
ra
ti
n
g
c
o
nve
r
t
er sy
s
tem
.
Li
t
era
t
ure
s
sh
o
w
t
ha
t
th
e
c
o
nve
n
tio
na
l si
x-p
u
l
s
e i
nve
rter s
y
s
te
ms
had
bee
n
w
i
d
el
y
use
d
.
H
o
w
e
v
e
r,
t
hi
s
s
y
s
t
e
m
i
n
t
r
o
d
u
ces
h
ar
m
onic
s
a
t
A
C
t
e
r
m
i
na
ls.
T
h
e
r
efore,
p
a
ssive
f
il
ters
are
dem
a
nded.
I
n
or
der
to
m
in
imiz
e
the
siz
e
of
t
he
p
a
ssi
ve
f
i
l
t
er
s,
t
h
i
s
paper
ha
s
pr
opos
e
d
t
o
rep
l
a
c
e
t
he
con
v
e
n
t
i
ona
l
r
e
gene
ra
ti
ve
i
n
v
e
r
ter
syste
m
w
ith
a
m
u
l
t
i
l
e
vel
c
o
n
verter
.
Tw
o
c
a
sca
d
e
d
t
o
p
o
l
og
i
e
s
m
u
l
tile
ve
l
c
o
nv
e
r
t
e
r,
n
a
m
el
y
Ca
sca
d
ed
H
-B
ri
dg
e
(
C
HB)
c
onv
erte
r
an
d
M
odu
la
r
M
u
lti
leve
l
C
o
n
v
erter
(M
MC)
a
r
e
revie
w
ed
a
nd
a
n
al
yse
d
i
n
t
h
is
p
ape
r
.
Tw
o
trac
t
i
o
n
s
ubs
tat
i
o
n
s
i
m
u
l
a
t
i
o
n
m
ode
l
s
a
r
e
d
eve
l
ope
d
an
d
in
te
gr
ated
w
i
t
h
a
C
H
B
o
r
a
n
M
M
C
a
s
i
t
s
r
e
c
u
p
e
r
a
t
i
n
g
c
o
n
v
e
r
t
e
r
.
B
o
t
h
C
H
B
a
n
d
M
M
C
are
de
si
gne
d
w
ith
t
he
a
i
m
t
o
p
r
od
u
c
e
a
n
i
ne-l
e
v
el
out
put
p
h
a
se
v
o
l
t
a
ge
u
si
ng
L
e
v
e
l
-Sh
i
ft
e
d
-P
u
l
se
-
W
idt
h
-M
odu
l
a
t
i
on
t
e
c
hn
iqu
e
.
Th
e
si
m
u
lat
i
on
re
sul
t
s
s
how
t
ha
t
M
M
C
i
s
m
ore
sui
t
ab
le
t
o
u
s
e
a
s
a
r
e
c
uperatin
g
co
nver
t
e
r
a
s
it
pr
od
uc
es
g
o
o
d
qua
l
ity
o
f
v
o
lta
ge
a
nd
c
u
rr
ent
w
a
ve
form
s.
T
h
e
T
o
t
al
H
a
r
m
o
nic
s
D
ist
o
rti
on
i
nde
xes
a
r
e
com
p
ly
w
ith
t
h
e
in
dus
trial
s
t
a
n
dard,
i.e
.
l
ess
than 8%
o
f
vol
t
a
ge
h
a
r
mon
i
c
a
nd
5%
o
f
c
u
rre
nt
har
mon
i
c.
H
ow
ever
,
t
h
e
l
i
n
e-li
ne
vo
lta
ge
s
pr
od
uc
ed
b
y
MM
C
a
r
e
sli
g
h
t
l
y
l
ow
e
r
t
ha
n
the
se
c
o
n
d
ary
w
i
nd
i
ng
of
t
he
r
e
c
t
i
fi
er
t
ransfor
m
e
r
r
ati
ng.
Th
is
i
ss
ue
c
a
n
b
e
so
lve
d
b
y
i
n
j
e
c
t
in
g
t
h
ird-or
d
e
r
har
m
o
n
i
c
v
ol
t
a
g
e
c
o
m
p
o
n
e
n
t
as
a
c
o
m
m
on
m
ode
s
i
gna
l
for
modu
la
ti
o
n
[2
4
]
,
[
25].
ACKNOW
LEDG
E
MEN
T
S
Th
e
au
th
o
r
s
are
pl
e
a
s
e
d
to
e
xp
ress
t
h
e
i
r
a
pprec
i
a
ti
on
t
o
th
e
Mi
ni
st
r
y
o
f
Ed
u
cati
o
n
(M
O
E
),
M
a
l
a
y
s
i
a
for
sp
o
n
sor
i
n
g
the
F
u
nd
a
m
e
n
ta
l
R
e
sear
ch
G
ra
nt
S
che
m
e
(F
R
G
S
)
t
o
c
ond
uc
t
this
r
e
s
e
a
rc
h.
P
rojec
t
C
o
d
e
:
F
R
G
S
/1/
2
01
6
/
TK
04
/U
N
I
TEN
/02/
1.
REFE
RENCES
[1]
C.
J
.
G
o
o
d
m
a
n,
"
Ov
ervi
ew
o
f
El
ectri
c
Rai
l
w
a
y
sy
st
e
m
s
and
the
ca
l
c
ulat
io
n
of
t
rain
p
erfo
rm
ance,"
in
Th
e
9
t
h
Ins
t
i
t
utio
n o
f
Eng
i
neer
in
g a
n
d
T
ech
no
log
y
Pr
of
ess
i
on
al
Develo
p
m
e
nt
Co
urse o
n
E
l
ectric T
r
acti
on
Sys
t
ems
,
M
a
nch
e
s
t
er,
pp
. 1-2
4,
2
0
06.
[2]
P
.
J
oh
ns
on
,
S
.
B
rown
,
"
A
s
i
m
pl
e
in
-cab
s
ched
ul
e
ad
vis
o
ry
s
yst
e
m
t
o
sa
v
e
e
ne
rg
y
a
nd
imp
r
ov
e
o
n
-
ti
me
p
e
rfor
ma
nc
e
,
"
in
IET Co
n
f
erence
on Railwa
y
Tracti
on
Systems
, B
i
r
min
g
h
a
m,
p
p
.
1
-5, 2
01
0.
[3]
V.
G
el
m
a
n
,
"
Brakin
g
energ
y
r
ecuperat
i
o
n
-rever
s
ible
t
hy
risto
r-co
nt
rolled
rect
i
f
i
e
rs
,"
IE
EE V
e
h
i
cu
la
r
T
echno
lo
g
y
M
a
gazin
e
,
vo
l. 4
, n
o.
3,
pp
.
82
-8
9
,
2
0
0
9
.
[4]
H.
I
b
a
io
nd
o,
A
.
Rom
o
,
"Kin
eti
c
e
nergy
recov
e
ry
o
n
rail
way
s
y
s
t
e
m
s
w
it
h
f
eed
back
t
o
t
h
e
g
r
id,
"
i
n
14
th
Int
e
rna
t
i
o
n
a
l
Power Electr
onics
an
d M
o
tio
n Co
n
t
ro
l
Confer
ence
, Oh
r
i
d
,
p
p
. 9
4-9
7
, 20
1
0
.
[5]
S
-
H
S
o
n
g
,
S
-
J
Jang,
H
-J
B
ang
,
C
-Y
W
on
,
"
R
eg
enerati
o
n
i
n
v
e
rter
s
ystem
f
o
r
DC
t
ract
ion
w
i
th
h
a
r
m
oni
c
red
u
ct
ion
capab
ili
ty," in
3
0
th
An
nu
al Confer
ence o
f
t
h
e IEEE
Ind. El
ectr
o
n
i
cs S
o
ci
e
t
y
,
Bu
san
,
p
p.
146
3-1
468,
2
00
4.
[6]
R.
D
.
W
h
it
e,
"
A
C
/
D
C
Railway
e
lect
rif
i
c
a
tio
n
an
d
prot
ecti
o
n
,
"
in
IET
1
3
t
h
P
r
ofess
i
o
nal D
evelo
p
men
t
Co
ur
se o
n
El
ectr
i
c T
r
a
c
ti
o
n
Sys
t
em
s
,
L
o
nd
on
, pp
. 1
-42
,
2
0
1
4
.
[7]
IEEE Recommended Prac
t
i
ce and Requi
r
ement
s
f
or Harmonic C
o
nt
r
o
l
i
n El
ectric
Po
wer S
y
st
em
s,
I
EEE,
2
014.
[8]
K. Hirah
ara, "Malay
s
ia
k
elan
a jay
a
li
n
e p
o
w
e
r supp
ly
sy
s
t
e
m,
"
M
e
id
en R
eview
, vo
l
.
15
6
, n
o.
3,
p
p
.
4
8
-
5
1
, 2
01
2.
[9]
M
.
R
aj
aratnam,
P
.
Gu
yard,
N.
M
azet,
"P
lan
o
f
i
n
s
t
r
uction
-
tract
i
o
n
pow
er
s
ub
-s
tatio
n
(TPSS
)
o
v
erall
s
y
stem
des
c
ript
io
n
,
"
Kons
ortiu
m CM
C-COL
A
S
-
UNIW
AY
,
K
uala
L
um
p
u
r,
201
6.
[10]
D.
I
an
nu
zz
i
,
F
.
M
u
ro
lo
,
P.Tri
c
o
li,
"
A
sample
a
ppli
cat
i
on
of
S
C
s
t
o
r
age
sy
st
em
f
o
r
s
ub
urb
a
n
tran
sit,"
in
Int.
C
o
n
f
.
El
ect S
y
st
e
m
f
o
r ai
rcraft,
r
a
ilway
and
s
h
ip p
r
op
u
l
si
on
,
B
olog
na,
p
p
.
1
-7
,
2
010
.
[11]
M
.
T
hon
g, A
.
Cheon
g
,
"
E
nergy
ef
fici
ency
in
si
n
g
apo
r
e
'
s
rapid
t
r
a
n
s
i
t
sy
ste
m
,"
Jo
urn
eys
,
pp
.
38
-4
7
,
2
012
.
[12]
M.
C
h
y
me
ra
,
A
.
C
.
Re
nfre
w,
e
t.a
l
,
"
S
im
pl
ifie
d
p
o
we
r
c
o
nve
rte
r
f
o
r
i
n
t
egrat
e
d
t
r
actio
n
en
ergy
s
to
rage,"
IEE
E
Tran
s. On
Ve
hic
u
lar
Te
c
h
no
lo
gy
,
vol.
6
0
,
n
o.
4
,
pp.
1
3
74-1
3
8
3
,
2
0
1
1
.
[13]
W.
A
.
G
.
d
e
Ja
ger,
M
.
H
u
i
zer,
E
.
K
.
H.
v
an
d
er
P
ols,
"
Implemen
t
ati
o
n
of
acti
v
e
regen
e
rat
i
on
u
ni
t
i
n
a
t
ract
io
n
substa
ti
on," in
16th
Eu
ro
pea
n
Co
nf
e
r
ence o
n
P
o
wer
El
ectr
o
n
i
cs and
Ap
p
l
icati
o
n
s
,
L
a
p
p
ee
nran
t
a
, p
p. 1-9
,
2
0
1
4
.
[14]
D.
C
o
r
n
i
c,
"
Efficien
t
recovery
o
f
braki
n
g
en
ergy
t
hro
ugh
a
r
ev
e
r
s
ible
d
c
subst
a
t
i
on,"
i
n
E
l
ec
tr
ical Systems for
Aircraf
t
,
R
a
ilway an
d S
h
i
p
Pro
p
ul
si
on
,
Bol
o
g
n
a,
pp.
1
-9,
2
010.
[15]
S
-
J
Jan
g
,
C-Y
Cho
i
,
C-H
Bae,
S
-H
S
on
g,
C
-Y
W
o
n
,
"S
tu
dy
of
r
eg
en
er
ati
o
n
p
o
w
e
r
co
nt
ro
l
in
vert
er
f
o
r
D
C
t
r
acto
n
with
acti
v
e
power
f
i
lter
ability,"
i
n
3
1
st A
nnu
a
l
Con
f
er
ence o
f
IE
EE
Ind
u
stria
l
E
l
ectr
onics
So
ciet
y
,
Ralei
g
h
,
pp.
12
71
-127
7,
2
0
0
5
.
[16]
A.
A
wallu
din,
C
.
L
.
T
o
h
,
"Harmo
nic
miti
ga
t
i
on
in
t
raction
su
ppl
y
s
u
b
s
t
a
ti
on
u
s
ing
cascaded
h
-b
ri
dg
e
con
v
erter,"
Int
e
rna
t
i
o
n
a
l
Jo
u
r
n
a
l of Po
wer
E
l
ectr
onics an
d
D
r
i
ve System
s
(
I
JPE
D
S)
, v
o
l
. 9
,
n
o
. 4
, p
p.
17
4
5
-
1
7
5
4
, 20
1
8
.
[17]
S
.
K
o
u
r
o
,
M
.
M
a
l
i
n
o
w
s
k
i
,
K
.
G
o
p
a
k
u
m
a
r
,
J
.
P
o
u
,
L
.
G
.
F
r
a
n
q
u
e
l
o
,
B
.
W
u
,
J
.
R
o
d
r
i
g
u
e
z
,
M
.
A
.
P
e
r
e
z
,
J
.
I
.
L
e
o
n
,
"Re
cen
t
adv
a
m
ces
a
nd
i
n
d
u
strial
a
ppl
icatio
ns
o
f
m
u
ltil
e
v
el
c
on
v
ert
e
rs,"
IE
E
E
. Tr
ans
.
on
Ind
.
Ele
c
tr
onics
,
vol.
57,
no
.
8
,
pp
.
2
5
5
3
-2
010
,
2
01
0.
[18]
J.
I
.
Leo
n
,
S
.
V
azq
uez,
L
.
G
.
F
ran
quel
o
,
"
M
u
ltilev
e
l
co
nv
erters
:
con
t
rol
an
d
m
o
du
la
ti
on
tech
ni
qu
es
f
o
r
t
h
e
ir
op
eratio
n
a
n
d
indus
tri
a
l
ap
p
l
ication
s
,
"
Pro
ceedin
gs
o
f
T
h
e
IEEE
,
vo
l.
1
05
, n
o.
1
1,
p
p
.
2
06
6
-
20
81
,
2
0
1
7
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SSN: 2088-
8694
Int J
P
o
w
El
e
c
&
D
ri S
yst
,
V
ol.
10,
N
o.
3
, S
e
p
2
0
1
9
:
115
7
– 1
166
1
166
[19]
I.
H
.
S
h
an
ono
,
N.
R
.
H.
A
b
dull
a
h,
A
.
M
u
h
a
mm
a
d
,
"
A
s
urv
e
y
of
m
ul
t
i
l
e
vel
vol
tage
s
o
u
rce
in
verter
t
o
p
o
l
o
g
ies
,
controls
a
nd
a
pplications,"
In
ternat
io
nal Jou
r
nal
o
f
Po
wer El
e
c
t
r
o
n
i
c
s an
d Dr
ive Sys
t
ems
(IJPEDS)
,
vo
l.
9
,
no.
3
,
pp
.
1
186
-12
0
1
, 2
018
[20]
S
.
K
.
Dash,
B.
N
ayak,
J.
B
.
S
a
hu,
"
sel
ectiv
e
h
a
rm
oni
c
el
imin
ati
on
o
f
an
e
lev
e
n
lev
e
l
i
n
v
e
rt
er
u
si
ng
wh
ale
op
timizati
o
n
tech
ni
qu
e
,
"
Inter
nati
o
n
a
l
Jou
r
nal
o
f
Po
wer
E
l
ect
ro
n
i
cs
a
nd
D
r
ive S
y
st
ems (
I
J
P
ED
S)
,
vo
l.
9
,
no.
4
,
pp.
19
44
-195
1,
2
0
1
8
.
[21]
C
.
L
.
T
o
h
,
L
.
E
.
N
o
r
u
m
,
"
V
H
D
L
i
m
p
l
em
en
tation
of
capaci
torv
ol
tag
e
b
a
lanci
ng
co
nt
rol
with
l
ev
el
-sh
i
fted
p
w
m
f
or
modular
mu
ltile
vel
converter,"
I
n
ter
n
a
t
i
onal
Jou
r
n
a
l
o
f
Po
wer
Elect
ro
nics
a
n
d
Dri
ve S
y
stem
(I
J
P
E
D
S
)
,
vol.
7
,
n
o.
1
,
p
p.
9
4 -
10
6,
2
0
1
6
.
[22]
Q
.
T
u
,
A
.
X
u
,
H
.
H
u
a
n
g
,
J
.
Z
h
a
n
g
,
"
P
a
r
a
m
e
t
e
r
d
e
s
i
g
n
p
r
i
n
c
i
p
l
e
o
f
th
e
arm
i
ndu
ctor
i
n
m
o
dular
m
ult
i
lev
e
l
conv
erter
bas
e
d
H
VDC,
"
i
n
Inter
nati
nal Co
nfer
ence o
n
P
o
wer
Sys
t
em T
echno
lo
gy
, Han
gzh
o
u
, pp
. 1
-6,
2
0
1
0
.
[23]
R.
V
i
a
l,
D
.
R
i
u,
N
.
Retiere,
"Si
m
ula
t
ing
calcula
t
i
on
s
and
opt
i
m
izati
on
desi
gn
o
f
a
new
HVD
C
su
pp
ly
pow
er
f
or
li
ght
r
ail
s
y
stem,
"
i
n
36
th A
nnual
Co
n
f
erence
o
n
IE
EE
In
dustr
ia
l El
ectr
o
n
i
cs
S
o
ciet
y
,
Glen
dale,
p
p
.
2
36
4-23
69
,
20
10
.
[24]
G
.
G
u
o
,
Q
.
S
o
n
g
,
W
.
Y
a
n
g
,
Y
.
W
a
n
g
,
W
.
L
i
u
,
H
.
R
a
o
,
S
.
X
u
,
"
A
p
p
l
icati
o
n
o
f
t
hird
-ord
er
h
arm
o
n
i
c
volt
a
ge
injection
i
n
a modular
mu
ltilevel
converter,"
IEEE Tr
ans
.
on
Ind. El
ectr
o
n
i
cs
,
vol.
65,
no.
7
,
pp.
5
2
6
0
-
5
2
7
1
,
201
8.
[25]
R.
L
i
,
J
.
E
.
F
let
c
her,
B
.
W
.
W
i
lliams,
"
I
nfluence
of
t
hird
h
arm
o
n
ic
i
njectio
n
on
mod
u
l
a
r
m
u
l
t
ilev
e
l
co
nv
erter-bas
ed
hi
gh
-voltag
e
di
r
ect cu
rrent
tran
s
m
i
s
s
i
o
n
sy
st
ems",
IET
Gener
a
t
i
on
T
r
ans
mi
ss
io
n &
Dis
t
r
i
b
u
ti
on
,
vo
l.
1
0,
n
o
. 1
1,
p
p
.
27
64
-277
0,
2
0
1
6
.
B
I
OGRAPHIES
O
F AUTHO
RS
Z
h
en
H
an
g
Cho
i
h
as
r
eceived
Fi
rs
t
Cl
ass
i
n
B
.
E
ng.
d
egree
i
n
e
l
ect
roni
cs
a
nd
co
m
m
u
n
i
cati
on
eng
i
n
eeri
n
g
f
r
om
U
niv
e
rsit
y
Te
n
a
ga
N
asi
onal
(U
NIT
E
N
),
K
aj
a
n
g
,
M
alay
s
i
a
in
2
01
8.
D
ur
in
g
h
i
s
stu
d
y
,
h
i
s
r
e
s
e
a
r
c
h
i
nte
r
e
s
ts
c
om
pr
ise
o
f
p
o
w
er
e
lect
ro
ni
cs,
f
i
e
l
d
p
r
og
ra
m
m
a
b
l
e
gate
a
rray
lo
gi
c
d
e
si
gn
an
d
crypt
og
raph
ic.
Besi
de
s
,
h
e
used
t
o
be
a
M
em
b
e
r
o
f
t
he
I
ET
Stu
d
ent
Ch
apter.
H
e
is
a
l
s
o
award
e
d
a
n
E
xcel
lent
S
t
u
dent
A
w
a
rd
f
ro
m
U
N
ITEN
.
Cu
rrentl
y
,
he i
s a
Desi
gn
P
r
o
j
ect
E
ngineer
i
n
Honeyw
ell
,
M
alay
s
ia
.
Ch
uen
Li
ng
T
oh
receiv
e
d
t
h
e
B.
E
ng
.
an
d
M.
E
n
g
.
deg
r
ee
in
e
l
ect
ri
c
a
l
en
gi
n
eerin
g,
b
o
t
h
f
r
om
U
niv
e
rsit
i
Tek
nol
ogi
M
alays
i
a
(UTM
),
S
ku
dai,
M
alay
si
a,
i
n
2
0
0
2
a
nd
20
05
res
p
ecti
v
el
y;
a
n
d
h
er
P
h
.
D
i
n
Electri
cal
P
o
w
er
E
ngi
neeri
n
g
f
r
o
m
N
orwe
gia
n
U
niv
e
rsi
t
y
o
f
S
c
i
e
nce
and
T
e
c
h
n
o
lo
gy
(
NTNU),
T
rond
he
i
m
,
No
rway,
i
n
2
014
.
Curr
en
tl
y,
s
he
i
s
a
S
e
n
i
o
r
L
ecturer
a
t
th
e
U
n
i
v
ersi
ti
T
enag
a
Nas
i
o
n
al,
K
a
jan
g
,
M
a
lays
ia.
H
er
t
each
in
g
and
research
in
te
r
e
st
s
in
c
l
u
d
e
t
he
f
i
e
ld
o
f
p
o
w
e
r
e
le
c
t
r
o
ni
c
s
,
m
o
t
o
r
d
r
iv
e
s
ystem
s
a
nd
f
i
e
ld
p
rogram
m
a
bl
e
gate
a
rray
applica
t
ions.
She
is
a
ls
o
a
Mem
b
er
o
f
IEEE
P
ow
er
E
l
e
ctro
nics
S
oc
i
e
ty
(
P
E
L
S
)
M
a
l
a
ysi
a
C
hapter.
M
u
ham
m
a
d
H
a
iri
b
i
n
Za
i
nol
H
ilm
i
r
ecei
ved
hi
s
Bach
elo
r
D
eg
re
e
in
E
l
ectri
cal
&
E
l
e
c
t
ronics
E
n
gineeri
n
g
f
r
o
m
U
n
i
versiti
T
e
naga
N
asional
(
UNITEN)
,
Ma
laysi
a
in
2
01
1
an
d
c
u
rrent
ly
p
u
rs
uin
g
M
as
t
e
r
i
n
E
l
ectrical
E
n
g
in
eering
at
U
N
I
T
E
N
.
H
e
w
o
rk
a
s
a
n
el
e
c
trical
e
n
g
i
n
eer
i
n
i
n
d
u
stria
l
s
in
ce
2
0
1
1
w
ith
g
o
o
d
tech
nical
k
n
o
wl
edge
i
n
Unint
e
rr
uptible
P
o
w
er
S
upply
(U
PS)
,
r
e
c
t
i
fi
ers
,
i
nverters,
ba
tt
e
r
ies
and
t
r
ansf
or
m
e
rs.
H
i
s
r
es
earch
i
n
t
erest
in
c
l
udes
p
o
w
e
r
el
ectron
i
cs
c
on
vert
er
d
es
ig
n
an
d
po
wer
s
y
s
t
e
m
.
He
i
s
reg
i
s
t
ered
w
i
t
h
th
e
Bo
ard
of
E
ngi
neers
M
a
l
a
ysi
a
(
BEM
)
a
n
d
a
l
s
o
a
grad
uat
e
m
em
ber
of
I
ns
tit
u
tio
n
of
E
n
g
i
n
eers
,
M
alay
sia (IEM
)
.
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