Internati
o
nal
Journal of P
o
wer Elect
roni
cs an
d
Drive
S
y
ste
m
(I
JPE
D
S)
Vol
.
4
,
No
. 2,
J
une
2
0
1
4
,
pp
. 16
5~
17
2
I
S
SN
: 208
8-8
6
9
4
1
65
Jo
urn
a
l
h
o
me
pa
ge
: h
ttp
://iaesjo
u
r
na
l.com/
o
n
lin
e/ind
e
x.ph
p
/
IJPEDS
A
Single-Phase Multilevel Curr
ent-Sour
c
e Converter
using
H-Bridge and DC Curr
ent Modules
Suros
o
*
, T
o
sh
i
h
i
k
o
No
guc
h
i
*
*
* Departement o
f
Electr
i
cal
Engineering
,
Jend
eral Soedirman University
, Indonesia
** Depart
em
ent
of El
ectr
i
c
a
l
and
El
ectron
i
cs
Eng
i
neer
ing,
S
h
izuo
ka Univers
i
t
y
,
J
a
pan
Article Info
A
B
STRAC
T
Article histo
r
y:
Received Ja
n
8, 2014
Rev
i
sed
Mar
19
, 20
14
Accepte
d Apr 2, 2014
This paper presents a different t
opolog
y
of
H-bridge based m
u
ltilev
e
l
current-source inverter (CSI). In
this ne
w inverter configuration,
an H-bridge
CSI is connected with a single or mo
re curr
ent modules to
generate a
m
u
ltileve
l outp
u
t curren
t
wav
e
form
with lowe
r di/dt
,
and
les
s
distortion.
Using the proposed m
u
ltilevel
CSI,
the number of the power switching
devices, and
isolated gate driv
e
circu
its can b
e
r
e
duced
. Moreov
er, chopp
er
bas
e
d DC curr
ent s
ources
ar
e pres
ent
e
d to
reduc
e the
in
ductor s
i
z
e
effectively
to be in micro-Henr
y
orde
r
,
and to
ens
u
re the bal
a
nce of th
e
intermediate
cur
r
ent levels
. The propos
ed topolog
y
is inh
e
ren
t
ly
ab
le
to
reduce
the indu
ctor condu
ction
losses if compared with
the convention
a
l
m
u
ltileve
l CSIs and the H-bridge
CSI. Seven-l
e
vel PW
M inverter
configurations
with non-isolated DC
current so
urces and with
a single DC
power source
are v
e
rified thr
ough co
mputer
simulations. F
u
rthermore,
laborator
y
proto
t
y
p
es of sev
e
n-level
CSI
is setup and tested
.
The r
e
sults
show that th
e in
verter
cir
c
uit works pr
operly
to
g
e
nerate
the multilevel outpu
t
current wav
e
for
m
with low harmonics cu
rrents, small inductors and with less
conduct
i
on losses which prov
es f
easibil
it
y
of the proposed
m
u
ltil
evel
CSI.
Keyword:
Cu
rren
t-Source Con
v
e
rter
Mu
ltilev
e
l-Inverter
Po
wer C
o
nve
rs
ion
Harm
oni
cs
Copyright ©
201
4 Institut
e
o
f
Ad
vanced
Engin
eer
ing and S
c
i
e
nce.
All rights re
se
rve
d
.
Co
rresp
ond
i
ng
Autho
r
:
Suros
o
,
Depa
rtem
ent of Elect
ri
cal
E
n
gi
nee
r
i
n
g,
Jenderal Soe
d
irm
a
n Uni
v
ersit
y
,
Jl. Mayj
en Su
ng
kon
o k
m
. 5
,
K
a
li
m
a
n
a
h
,
Pur
b
alingg
a, Jawa Teng
ah
,
I
ndon
esia.
Em
a
il: su
ro
so
.t
e.un
so
ed@g
m
a
il.co
m
1.
INTRODUCTION
So
m
e
circu
it
co
nfigu
r
ation
s
of m
u
ltilev
e
l
curren
t-
sou
r
ce inv
e
rters (C
SI)
h
a
ve
b
e
en presen
ted i
n
so
m
e
research
p
a
p
e
rs.
A
trad
i
tio
n
a
l
way to
produ
ce a
m
u
ltil
ev
el cu
rren
t
wav
e
fo
rm
is b
y
co
nn
ecting
some H-
Brid
g
e
CSIs in p
a
rallel [1
], [2].
Th
is inv
e
rter circu
it
is th
e
du
al of cascad
e
H-b
r
i
d
g
e
m
u
lti
lev
e
l vo
ltag
e
so
urce
inve
rter (VSI). Unfortunately
,
the
nee
d
of i
s
ol
at
ed
DC
cu
rr
ent
so
ur
ces,
po
wer
de
vi
ces co
unt
a
n
d t
h
ei
r
g
a
t
i
n
g
circu
its are some p
r
ob
lem
s
o
f
th
is inv
e
rter
circu
it.
Referen
ce [3
] p
r
esen
t
e
d
th
e m
u
ltilev
e
l CSI to
po
logy u
s
in
g
H-
bri
dge
a
n
d
i
n
d
u
ct
o
r
-cel
l
.
T
h
i
s
t
o
p
o
l
o
gy
si
m
p
li
fi
es t
h
e
re
qui
rem
e
nt
of
i
s
ol
at
ed
DC
cu
rre
nt
s
o
u
r
ces
i
n
t
h
e
p
a
rallel H-bridg
e
m
u
lti
lev
e
l CSI.
Ano
t
h
e
r circu
it con
f
i
guratio
n
of m
u
ltil
ev
el CSI is created
b
y
u
tilizin
g
m
u
lti-
cell co
n
f
i
g
urat
io
n
o
f
m
u
ltile
v
e
l CSI
[1
],
[4
], [8
], wh
ich is th
e du
al of flyin
g
cap
acito
r m
u
lti
lev
e
l
VSI.
Balan
c
in
g contro
l co
m
p
lex
i
t
y
o
f
t
h
e i
n
termed
iate lev
e
l
cu
rren
ts is a
prob
lem
o
f
th
is in
v
e
rter
[8
].
Sev
e
ral
cont
rol
t
ech
ni
q
u
es
ha
ve
bee
n
prese
n
t
e
d
t
o
c
o
nt
r
o
l
t
h
e
bal
a
nce of th
e in
termed
iate lev
e
l cu
rren
ts in [5
] an
d
[6
],
h
o
wev
e
r t
h
e inv
e
rter still requ
ires
v
e
ry lar
g
e in
size of
th
e in
term
ed
iate i
n
du
ctors
(>100
m
H
). Referen
ce [7
]
p
r
esen
ted ano
t
h
e
r circu
it configu
r
ation
o
f
m
u
l
tilev
e
l
CSI wh
ich
is a mo
d
i
fied
co
nfigu
r
ation
o
f
p
a
rallel H-
b
r
i
d
g
e
m
u
ltile
v
e
l CSI.
Ho
wev
e
r
,
ev
en 400
m
H
bu
lk
y
in
du
ctors
h
a
ve b
e
en
u
s
ed
,
lar
g
e
ripp
les
o
f
th
e
sm
o
o
t
h
i
n
g
i
n
du
ctor curren
t
s
are still ex
ist.
Th
ese
ripp
les
will d
i
sto
r
t the o
u
t
p
u
t
cu
rren
t wav
e
fo
rm
o
f
t
h
e
in
v
e
rter
. Moreo
v
e
r
,
t
h
e cu
mb
erso
m
e
in
du
cto
r
s
will b
e
co
stly and
lim
i
t
th
e ap
p
licatio
n of t
h
e i
n
verter
.
Referen
ce
[9
] p
r
esen
ted
th
e co
nfigu
r
ation
o
f
si
n
g
l
e
-rating
indu
cto
r
cell
m
u
ltilev
e
l CSI wh
ich
is t
h
e d
u
al
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-86
94
I
J
PED
S
Vo
l. 4
,
No
. 2
,
Jun
e
2
014
:
16
5
–
17
2
16
6
circu
it of im
p
r
o
v
e
d
d
i
od
e-clam
p
e
d
m
u
ltilev
e
l
VSI.
Th
e
mu
lti-cell an
d sin
g
l
e-rating
indu
ctor cell top
o
lo
g
i
es
use
ve
ry
l
a
r
g
e
i
n
t
e
rm
edi
a
t
e
i
nduct
o
rs
a
dde
d
i
n
t
h
e
i
n
vert
e
r
ci
rcui
t
t
o
o
b
t
a
i
n
t
h
e
i
n
t
e
rm
edi
a
t
e
cu
rre
nt
l
e
vel
s
,
in
stead
o
f
th
e sm
o
o
t
h
i
n
g
inducto
r
s
u
s
ed
fo
r
D
C
cur
r
e
n
t
g
e
n
e
r
a
tion
.
Th
ese in
du
ctor
s w
i
l
l
cau
se m
o
r
e
lo
sses to
the inverter ci
rcuits aside
from losses cause
d by t
h
e
sm
oot
hi
n
g
i
n
d
u
ct
or
s
and
i
n
vert
er
’
s
po
we
r de
vi
ce
s.
Th
e
in
v
e
rter circu
its with m
o
re in
term
ed
ia
te in
d
u
cto
r
s
will h
a
v
e
lo
wer ef
ficien
cy
.
In th
is
p
a
p
e
r
,
a n
e
w ci
rcu
it con
f
i
g
uratio
n
o
f
m
u
l
tilev
e
l CSI, ap
p
l
ying
an
H-b
r
i
d
g
e
CSI t
o
po
log
y
and
cu
rren
t m
o
du
l
e
s with cap
ab
i
lities o
f
redu
ci
n
g
iso
l
ated
g
a
t
e
driv
e ci
rcu
i
t
s
, redu
cing
i
n
d
u
c
t
o
r size, and
with
lowe
r induct
o
r conduction l
o
sses are
prese
n
ted.
T
h
e chop
per base
d
DC c
u
rrent s
o
urces
are also
prese
n
ted to
co
n
t
ro
l t
h
e in
t
e
rm
ed
iate lev
e
l cu
rren
ts u
s
i
n
g
sm
all
si
ze of i
n
d
u
ct
or
s.
T
h
e
ope
rat
i
o
n
per
f
o
r
m
a
nce o
f
t
h
e
p
r
op
o
s
ed
m
u
ltilev
e
l CSI is
ex
am
in
ed
and is v
a
lid
ated
t
h
rou
g
h
so
m
e
co
m
p
u
t
er simu
latio
n
s
. Furtherm
o
r
e,
l
a
bo
rat
o
ry
e
x
p
e
ri
m
e
nt
al
prot
ot
y
p
es
of se
ve
n-l
e
vel
C
S
Is
w
e
re set
u
p
t
o
v
e
ri
fy
t
h
e
pr
ope
r o
p
erat
i
o
n
of t
h
e ne
w
t
o
p
o
l
o
gy
,
usi
n
g t
h
e
p
o
w
er
M
O
SFET
s
i
n
seri
es wi
t
h
bl
ocki
n
g
di
o
d
es.
2.
CIR
C
U
IT CO
NFIG
U
RATI
O
N A
N
D
PR
I
NCI
PLE
OPE
RATI
O
N
2.
1.
Operation Pri
n
ciple of Inve
rter
Circuit
Fi
gu
re 1.
The
c
u
r
r
ent
-
m
odul
e ci
rcui
t
,
a
n
d
i
t
s
basi
c ope
rat
i
o
n
[
8
]
Fi
gu
re 1 sh
o
w
s t
h
e ci
rcui
t
confi
g
u
r
at
i
on
of
t
h
e cur
r
ent
-
m
odul
e, a
nd i
t
s
b
a
si
c operat
i
o
n.
The cur
r
ent
m
odul
e i
s
con
s
t
r
uct
e
d
by
a DC
cur
r
e
n
t
so
urce
wi
t
h
a un
i
d
i
r
ect
i
onal
p
o
w
er s
w
i
t
c
h S,
and a
di
o
d
e [8
]
.
The
novel circ
uit c
o
nfiguration of the m
u
ltilevel CSI is
deri
ve
d by c
o
nnecting a single
or m
o
re m
odules
wit
h
t
h
e
H-
bri
dge
C
S
I
as sh
ow
n i
n
t
h
e schem
a
t
i
c
diagram
of t
h
e
p
r
o
p
o
sed
m
u
l
t
ilevel
C
S
I i
n
Fi
gu
re
2 a
nd
Fi
g
u
re
3
.
Th
e curren
t
mo
du
les wo
rk
for
m
u
ltilev
e
l o
u
t
p
u
t
curren
t
wa
v
e
fo
rm
g
e
n
e
rat
i
o
n
.
A fiv
e
-level cu
rren
t
waveform
i
s
ge
nerat
e
d
b
y
addi
ng
a si
n
g
l
e
cu
rre
nt
-m
odul
e,
a se
ve
n-l
e
vel
cu
rre
nt
w
a
vef
o
rm
i
s
ach
i
e
ved
by
c
o
n
n
ect
i
n
g
two
cu
rren
t-mo
du
les
w
ith
the th
ree-lev
e
l
H-Bridg
e
CSI, an
d so
o
n
.
The
l
e
vel
n
u
m
b
er of t
h
e
out
put
c
u
r
r
en
t
wave
f
o
rm
and
t
h
e co
u
n
t
o
f
t
h
e cu
rre
nt
-m
odu
l
e
s can
be
o
b
t
a
i
n
ed
fr
om
t
h
e e
quat
i
o
n:
U
V
2
3
,
(
1
)
Whe
r
e
V
is th
e lev
e
l nu
m
b
er
o
f
th
e
ou
tpu
t
cu
rren
t and
U
i
s
t
h
e c
o
u
n
t
of
c
u
r
r
ent
-
m
odul
es
.
Fi
gu
re
2.
Pr
o
p
o
se
d fi
ve-l
e
v
el
C
S
I
Fi
gu
re
3.
Pr
o
p
o
se
d se
ven
-
l
e
v
e
l
C
S
I
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
PED
S
I
S
SN
:
208
8-8
6
9
4
A Si
ngle-Phase
Multilevel Current-Sour
ce
Converter using H-Bri
d
ge an
d DC
Current M
o
dules
(Suroso)
16
7
The num
b
er of the DC curre
nt sources
,
als
o
rep
r
ese
n
t
i
ng t
h
e num
ber o
f
t
h
e sm
oot
hi
ng i
n
duct
o
rs i
n
th
e real p
o
wer circu
its. Fo
r
th
e sam
e
a
m
p
l
itu
d
e
of th
e ou
tpu
t
cu
rren
t,
th
e a
m
p
litu
d
e
s o
f
th
e DC curren
t
so
urces in
th
e
p
r
op
o
s
ed
m
u
lti
lev
e
l CSI are smaller th
an
th
e a
m
p
litu
d
e
o
f
th
e DC cu
rren
t so
urce in
th
e th
ree-
lev
e
l H-B
r
idg
e
CSI. M
o
reov
er, all DC
c
u
rre
n
t sources are
connected at th
e sam
e
point, hence the is
olated DC
cu
rren
t
sou
r
ces u
s
ed
i
n
th
e co
nv
en
tio
n
a
l
p
a
rallel H-Bri
dge m
u
lti
lev
e
l CSI are
n
o
t
n
e
cessary in th
is i
n
v
e
rter
cir
c
u
it conf
igur
atio
n.
As s
h
ow
n
i
n
Fi
gu
re
2
an
d
Fi
gu
re
3,
t
h
e
po
we
r s
w
i
t
c
he
s S
3
,
S4
,
S5
and
S
6
a
r
e c
o
nnect
e
d
at
a
comm
on-emitter line or
at th
e sam
e
p
o
t
ential p
o
i
n
t
. As a resu
lt,
e
v
en
the num
b
er of
th
e cu
rren
t-mo
du
les
increases
, the
circuit nee
d
s on
ly th
ree iso
l
ated
g
a
te driv
e
circu
its. Tw
o
i
s
ol
at
ed gat
i
ng ci
rcui
t
s
are us
ed
t
o
dri
v
e t
h
e p
o
w
er swi
t
c
hes
S1
and S
2
, a
n
d
one m
o
re t
o
g
a
t
i
ng t
h
e
po
we
r swi
t
c
hes
S3
,
S4, S
5
a
nd
S
6
. T
h
i
s
featu
r
e lead
s to
th
e redu
ctio
n in
th
e nu
m
b
er o
f
iso
l
ated
g
a
t
e
d
r
iv
e ci
rcu
its u
s
ed
i
n
m
u
lti
l
e
v
e
l CSI circu
its [8
]
.
The
out
put current le
vels of t
h
e fi
ve-le
v
el C
S
I a
r
e +I, +I
/
2
,
0
,
-I/2
, and
-I cu
rren
t
lev
e
ls. Fo
r
sev
e
n-lev
e
l
CSI,
th
e ou
tpu
t
cu
rren
t
lev
e
ls are +I, +2
I/
3
,
+I/3
,
0
,
-
I
/
3
,
-2
I
/
3,
an
d -I
cu
rr
en
t lev
e
ls.
Tabl
e
1.
Swi
t
c
h st
at
es
of
p
r
o
p
o
se
d se
ven
-
l
e
v
e
l
C
S
I
S1
S2
S3 S4 S5 S6
Outp
ut
c
u
rren
t
1
0
1 0 0
0
+I
1
0
1 0 0
1
+2I
/
3
1
0
1 0 1
1
+I
/3
1
0
0 1 1
1
0
0
1
0 1 1
1
-
I
/
3
0
1
0 1 0
1
-
2
I
/
3
0
1
0 1 0
0
-
I
The s
w
itching
state com
b
inations
require
d
t
o
ge
ne
rate a sev
e
n-lev
e
l cu
rren
t wav
e
fo
rm
are listed
in
TAB
LE 1
.
The
seven
-
l
e
vel
o
u
t
put
cu
rre
nt
(+
I, +2
I/
3, +I/
3
,
+0, -
I
/
3
, -
2
I/
3
and -
I
cu
rre
nt
-l
evel
s) are
gene
rat
e
d
as fo
llo
ws:
a)
Cu
rren
t lev
e
l +I: S2
,
S4, S5
an
d S6
ar
e turn
ed
-o
ff
, wh
ile S1 and
S3 ar
e tu
rn
ed-o
n,
m
a
k
i
n
g
th
e cu
rr
en
t +I
flow to th
e l
o
ad
.
b)
Cu
rren
t lev
e
l
+2
I/
3
:
S2
,
S4
an
d S5
are turn
ed-o
ff,
wh
ile S1, S3
and
S6
are turn
ed-on
,
m
a
k
i
n
g
th
e
current +
2
I/3
fl
ows
to t
h
e l
o
ad.
c)
Cu
rren
t lev
e
l +I/3
: S2
and
S4
are tu
rn
ed
-o
ff,
wh
ile
S
1
, S
3
,
S5 a
nd S
6
a
r
e
t
u
r
n
ed
-o
n, m
a
ki
ng t
h
e c
u
r
r
e
n
t
+
I
/
3
f
l
o
w
s
to
th
e
l
o
ad
.
d)
Cu
rren
t lev
e
l 0: S1
, S4
, S5
and
S6
are tu
rn
ed-on
,
a
n
d
S2
,
S3
ar
e tur
n
ed-
o
ff
m
a
king the current loops for
every
DC c
u
rrent s
o
urces. No
cu
rren
t
flows to
th
e lo
ad
.
e)
Cu
rren
t lev
e
l –I/3
: S1
and
S3
are turn
ed-off,
wh
ile
S
2
,
S
4
,
S5 a
n
d S
6
a
r
e
t
u
r
n
ed
-o
n,
m
a
ki
ng t
h
e c
u
r
r
en
t
–
I
/
3
fl
o
w
s to the lo
ad.
f)
C
u
r
r
ent
l
e
vel
-
2
I/
3:
S
1
,
S3
an
d S
5
a
r
e t
u
r
n
e
d
-o
ff
,
whi
l
e
S
2
,
S4 a
n
d S
6
are
t
u
r
n
e
d
-
o
n
,
m
a
ki
ng
t
h
e
cu
rre
nt
-2
I/3
flo
w
s t
o
t
h
e loa
d
.
g)
Cu
rren
t lev
e
l -I: S1, S3
,
S5 an
d S6
are tu
rn
ed
-o
ff,
wh
i
l
e
S2
an
d S
4
a
r
e t
u
r
n
ed
-
o
n
,
m
a
ki
ng t
h
e
cu
rre
nt
s
–I
flows to th
e l
o
ad
.
T
a
b
l
e 2. Co
m
p
ar
ison
b
e
tw
een fo
ur
typ
e
s of
fiv
e
-
l
ev
el C
S
I
s
[
8
]
Multilevel CSI
Types
Multi-cell
Typ
e
Paralleled H-bridg
e
Typ
e
Single-
r
a
ting indu
ctor
cell T
y
pe
H-
br
idge with ind
u
ctor
cell type
Pr
oposed
T
opology
Pow
er s
w
itches
8 8
8
8
5
Diodes
8 8
8
8
6
Inductors
3 2
5
2
2
Isolated gate drive
circuits
4 4
4
4
3
Th
e cou
n
t
redu
ctio
n of ci
rcu
it co
m
p
o
n
en
t
s
attain
ed
b
y
u
s
i
n
g th
e
pro
p
o
s
ed
m
u
ltil
ev
el CSI is
prese
n
t
e
d
i
n
T
a
bl
e 2.
Thi
s
t
a
bl
e p
r
ese
n
t
s
t
h
e com
pone
nt
s
cou
n
t
i
n
v
o
l
v
e
d
t
o
co
nst
r
uct
a
fi
ve-l
e
v
el
C
S
I
ci
rcui
t
s
usi
n
g t
h
e
p
r
o
p
o
se
d fi
ve
-l
evel
i
nve
rt
er ci
rc
u
i
t
s
, and t
h
r
ee
othe
r inverter
circuits. T
h
e t
o
tal of t
h
e inductors
i
n
cl
ude
s t
h
e s
m
oot
hi
ng i
n
d
u
c
t
o
rs, a
n
d t
h
e i
n
t
e
rm
edi
a
t
e
i
nduct
o
rs
. T
h
e s
m
oot
hi
ng i
n
d
u
c
t
o
rs a
r
e t
h
e i
n
duct
o
rs
con
n
ect
ed t
o
t
h
e DC
p
o
w
er
sou
r
ce t
o
gene
rat
e
t
h
e DC
cu
rre
nt
so
urces
. The i
n
t
e
rm
edi
a
t
e
i
nduct
o
rs a
r
e us
e
d
for the interm
ediate level currents ge
neration. The
re
duction in com
pone
nt num
bers
will be
m
o
re signi
ficant
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-86
94
I
J
PED
S
Vo
l. 4
,
No
. 2
,
Jun
e
2
014
:
16
5
–
17
2
16
8
fo
r hi
g
h
e
r
l
e
ve
l
C
S
I. As an e
x
am
pl
e, for se
ven
-
l
e
vel
C
S
I
,
t
h
e paral
l
e
l
e
d
H-B
r
i
d
ge co
nfi
g
u
r
at
i
o
n nee
d
s
t
w
el
ve
po
we
r s
w
i
t
c
he
s,
but
t
h
e
pr
o
p
o
se
d se
ven
-
l
e
v
e
l
C
S
I
nee
d
s
onl
y
si
x
po
we
r s
w
i
t
c
hes,
5
0
%
re
du
ced
,
wi
t
h
t
h
e
sam
e
num
ber of i
n
d
u
ct
o
r
s. T
h
e n
u
m
b
er of t
h
e i
n
duct
o
rs
is fewer if co
m
p
ared
with
th
e
m
u
l
ti-cell
m
u
l
t
ilev
e
l
CSI, and
sing
l
e
-rating
indu
cto
r
cell m
u
ltile
v
e
l CSI top
o
l
og
ies. A fiv
e
-lev
el
sing
le-ratin
g
ind
u
c
t
o
r cell
CSI
n
eeds f
i
v
e
inducto
r
s
, th
e
pr
opo
sed
f
i
v
e
-
l
ev
el CSI
n
e
ed
s
on
ly tw
o
i
n
du
ctors, 60
% r
e
du
ced.
2.2.
DC
Curr
e
n
t Sour
ce Ge
nerati
on
The DC curre
nt source
s are a
b
sol
u
tely
requ
ired
in
th
e cu
rren
t
-so
u
rce inverter typ
e
. In
th
is p
a
p
e
r, the
DC c
u
rrent
-
sources
are
ac
qui
red by
usi
n
g buck-c
hopper ci
rcui
t
s
c
o
nnect
e
d
wi
t
h
a
DC
p
o
we
r s
o
urce
[
8
]
,
[1
0]
,
[1
1]
.
The DC powe
r
source (V
in
) ca
n be a
ph
ot
o
v
o
l
t
a
i
c
sy
st
em
, fuel
-c
e
ll, b
a
ttery o
r
rectifier circu
its. Th
e
cho
p
p
er
w
o
r
k
s
t
o
pr
o
v
i
d
e a c
onst
a
nt
DC
c
u
rre
nt
so
urce
f
o
r t
h
e H
-
B
r
i
dge
C
S
I an
d c
u
r
r
e
n
t
-
m
odul
e ci
rc
ui
t
s
.
The c
h
o
p
p
er ci
rcui
t
i
s
com
p
o
s
ed
by
a p
o
w
e
r
swi
t
c
h, a
n
i
n
duct
o
r
(c
ho
ke)
an
d a
po
wer
d
i
ode.
The
co
nt
rol
l
e
d
po
we
r swi
t
c
h
wo
rk
s t
o
cont
r
o
l
l
t
h
e sm
oot
hi
ng i
n
d
u
ct
o
r’s c
u
r
r
ent
,
a
nd t
o
r
e
duce t
h
e sm
oot
hi
n
g
i
n
duct
o
r si
ze.
The
po
we
r di
o
d
e (
D
F
)
i
s
ap
pl
i
e
d t
o
kee
p
co
nt
i
n
u
o
u
s c
u
r
r
e
n
t
pat
h
o
f
t
h
e s
m
oot
hi
ng i
n
d
u
c
t
o
r’
s cu
rre
nt
.
Fi
gu
re
5 an
d Fi
g
u
re
6 sh
o
w
t
h
e c
o
n
f
i
g
urat
i
o
ns
of fi
ve-l
e
v
el
and se
ve
n-l
e
vel
C
S
Is wi
t
h
D
C
curre
nt
ge
n
e
rat
i
o
n
circu
its.
It shou
ld
b
e
no
ted
t
h
at on
ly a sing
le DC
po
wer sou
r
ce (V
in
)
is co
nn
ected
t
o
circu
its to
ob
tain
m
u
l
tip
le n
o
n
-iso
lated
DC curren
t
-so
u
rces.
Th
e propo
se
d
m
u
l
tilev
e
l CSI d
o
e
s
n
o
t
n
e
ed iso
l
ated
DC cu
rrent
sources
.
Fi
gu
re
5.
Fi
ve
-
l
evel
C
S
I
with
DC
cu
rren
t-sou
r
ces
circu
its [8
]
Fi
gu
re
6.
Se
ve
n-l
e
vel
C
S
I
wi
t
h
DC
c
u
r
r
ent
s
o
u
r
ces
circu
its [8
]
2.
3.
Cond
ucti
on L
o
sses
of I
nductors
Th
is section d
i
scu
sses th
e indu
cto
r
’
s
cond
u
c
tio
n
l
o
sses i
n
m
u
l
tilev
e
l CSIs. Fro
m
au
tho
r
’
s
literature
search resu
lt, t
h
e size
of th
e in
du
ctor
s
u
s
ed
i
n
th
e co
nv
en
tio
n
a
l m
u
ltilev
e
l CSI t
o
po
log
i
es is v
e
ry lar
g
e, m
o
re
th
an
10
0
m
H
[1
]-[7
], [9
].
These bu
lk
y inducto
rs
w
ill b
e
the m
a
in
cau
se
of lo
sses wh
ich
cau
se th
e ef
ficien
cy
o
f
t
h
e m
u
ltilev
e
l CSI m
u
ch
l
o
wer than
t
h
e
m
u
l
tilev
e
l
VSI. In
th
e pro
p
o
s
ed
topo
log
y
, if th
e am
p
litu
d
e
o
f
th
e
V
-l
evel
out
put
cur
r
ent
i
s
I,
and t
h
e
num
ber o
f
t
h
e c
u
r
r
e
nt
-m
odul
e i
s
U
, t
h
e c
u
rre
nt
fl
o
w
i
n
g t
h
r
o
u
gh t
h
e
sm
oot
hi
ng
i
n
d
u
ct
o
r
I
LN
is
expresse
d as:
)
1
(
U
I
I
LN
,
(
2
)
If t
h
e sm
oot
hi
ng i
n
d
u
ct
o
r
ha
s resi
st
ance R
L
, th
e in
du
ctor
’s co
ndu
ctio
n
l
o
sses (P
Lc
) cau
s
ed
b
y
th
is cu
rren
t is
expresse
d as:
L
Lc
R
U
I
P
2
1
(
3
)
Th
e t
o
tal con
d
u
c
tio
n lo
sses
du
e to th
e i
n
d
u
c
to
rs i
n
a
V
-le
v
e
l
CSI
(P
Lc
-
V
) ca
n
be calculate
d as:
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
PED
S
I
S
SN
:
208
8-8
6
9
4
A Si
ngle-Phase
Multilevel Current-Sour
ce
Converter using H-Bri
d
ge an
d DC
Current M
o
dules
(Suroso)
16
9
1
1
)
1
(
2
2
U
R
I
R
U
I
U
P
L
L
V
Lc
(
4
)
In t
h
e fi
ve-l
e
v
el
C
S
I, t
h
e cu
r
r
ent
fl
o
w
i
n
g t
h
ro
u
gh t
h
e sm
oot
hi
n
g
i
n
d
u
ct
o
r
s i
s
hal
f
t
h
e
a
m
pli
t
ude o
f
t
h
e fi
ve
-l
evel
out
put
c
u
r
r
ent
.
In t
h
e seve
n
-
l
e
vel
C
S
I c
o
n
f
i
g
u
r
at
i
o
n, t
h
e a
m
pli
t
ude o
f
t
h
e sm
oot
hi
ng i
n
duct
o
r
cur
r
ent
s
i
s
o
n
e
t
h
i
r
d
of t
h
e se
v
e
n-l
e
vel
out
put
curre
nt
, a
nd s
o
f
o
rt
h
.
The
hi
ghe
r t
h
e l
e
vel
-
num
ber o
f
t
h
e
out
put
cur
r
ent
l
e
a
d
s t
o
sm
al
l
e
r cur
r
e
nt
s fl
owi
n
g
t
h
r
o
ug
h t
h
e sm
oot
hi
n
g
i
n
d
u
ct
ors
as e
x
press
e
d i
n
(
2
)
.
T
h
e
r
efo
r
e, i
t
redu
ces th
e to
t
a
l co
nd
u
c
tion
lo
ss (P
Lc
-
V
) o
f
t
h
e i
ndu
ct
or
s as sho
w
n i
n
Fi
g
u
r
e 7. The t
o
tal inductor’s conduction
loss o
f
the
five
-level CSI
(P
Lc
-
5
)
is h
a
lf
t
h
e ind
u
c
t
o
r’
s co
nductio
n
lo
ss of
the th
r
e
e-
lev
e
l H-
Br
idg
e
CSI
(P
Lc
-
3
).
Th
e t
o
tal in
du
cto
r
’s co
ndu
ction
loss
o
f
sev
e
n-lev
e
l CSI
(P
Lc
-
7
) is
o
n
e
th
ird
o
f
th
e i
n
du
ctor’s co
ndu
ctio
n l
o
ss
of
t
h
e H
-
B
r
i
dge
C
S
I, a
n
d s
o
fo
r
t
h [
8
]
.
Fi
gu
re
7.
C
h
a
r
act
eri
s
t
i
c
s of
c
o
n
d
u
ct
i
o
n
l
o
ss
of
t
h
e sm
oot
hi
ng
i
n
duct
o
rs
[
8
]
2.4. Curre
nt Regulator
and
Pulse
Wid
t
h
Modulation (PWM) Tecniq
ue
Propo
rtion
a
l i
n
tegral (PI)
cu
rren
t
regu
lators are
sep
a
rately e
m
p
l
o
y
ed
to
regu
late the sm
o
o
t
h
i
ng
in
du
ctor
s’
s cu
rr
en
t
(I
L
)
.
Th
e sw
itch
i
ng
sign
als of
t
h
e chopp
er
’
s
pow
er sw
itch
e
s ar
e
p
r
o
d
u
c
ed
b
y
com
p
ar
in
g
the error of the
m
easure
d
sm
oothing
in
du
c
t
or
’
s
cu
rr
en
ts
,
and
a
s
a
w
t
oo
th
ca
r
r
i
e
r
w
a
v
e
fo
rm u
s
in
g
co
mp
a
r
a
t
or
circu
its.
Th
e
ou
pu
t si
g
n
als
will d
e
term
in
e th
e
op
eration
of th
e ch
opp
er
’
s
con
t
ro
lled
power switch
e
s t
o
attain
stable DC c
u
rrent-s
o
urces
of
th
e inv
e
r
t
er
circu
its [8
]-
[1
1
]
.
Fo
r th
e m
o
d
u
latio
n
techn
i
qu
e,
a m
u
lti-carrier w
ith level-sh
ifted
b
a
sed
si
n
u
s
o
i
d
a
l
p
u
l
se wi
d
t
h
m
odul
at
i
o
n
(P
WM
)
st
rat
e
gy
i
s
ap
pl
i
e
d
t
o
c
ont
r
o
l
t
h
e
i
nve
rt
er
’
s
p
o
w
er s
w
i
t
c
hes
.
Som
e
triangular carrie
r
wav
e
fo
rm
s with
th
e sam
e
p
h
a
se and
frequ
e
ncy are u
tilized
in
th
is techn
i
qu
e
.
T
h
e funda
m
ental
output current
fre
que
ncy
of
t
h
e i
n
ve
rt
er i
s
det
e
rm
i
n
ed by
t
h
e
fre
que
ncy
o
f
t
h
e
m
odul
at
ed si
g
n
al
(a
refe
rence
si
n
u
s
oi
dal
wave
f
o
rm
).
T
h
e s
w
i
t
c
hi
n
g
fre
que
ncy
of
t
h
e i
n
vert
er
’
s
po
we
r s
w
i
t
c
he
s i
s
defi
ned
b
y
t
h
e
fre
que
n
c
y
of
trian
g
u
l
ar
carrier wav
e
form
s.
A
t
o
tal,
(V
-1
)
o
f
triangu
lar carrier
wav
e
fo
rm
s are
requ
ired
i
n
th
e
V
-le
v
el o
u
tp
ut
cur
r
ent
wa
vef
o
rm
generat
i
o
n
of
t
h
e i
nve
rt
er
ci
rcui
t
s
[
8
]
-
[
1
4
]
.
Tabl
e
3. T
e
st
p
a
ram
e
t
e
rs of i
n
vert
er
ci
rc
ui
t
s
Sm
oothing inducto
r
s
600
H
DC power
sour
ce
voltage
160 V
Switching fr
equen
c
y
of inver
t
er
22 kHz
Filter c
a
pacitor
5
F
Lo
ad
R
= 6.
5
,
L
=1.2 mH
Output cur
r
e
nt fr
equency
60 Hz
Evaluation Warning : The document was created with Spire.PDF for Python.
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. 2
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2
17
0
3.
Com
p
uter
Si
mulati
on and Ex
perimental Test
Results
The
ope
rat
i
o
n
of t
h
e
pr
op
os
ed t
o
p
o
l
o
gy
i
s
t
e
st
ed t
h
r
o
ug
h com
put
er
si
m
u
l
a
t
i
on an
d
expe
ri
m
e
nt
al
pr
ot
ot
y
p
e
i
n
l
a
bo
rat
o
ry
.
T
h
e
seve
n-l
e
vel
C
S
I c
o
n
f
i
g
ura
t
i
on as
s
h
o
w
n
i
n
Fi
g
u
re
6
was t
e
st
ed
by
usi
n
g
com
put
er si
m
u
l
a
t
i
on wi
t
h
PS
I
M
soft
ware
.
T
h
e
param
e
t
e
rs of
tested t
h
e inverter circ
uits
are listed i
n
T
a
ble 3.
Fi
gu
re
8 s
h
ow
s t
h
e c
o
m
put
er
sim
u
l
a
t
i
on re
s
u
l
t
s
o
f
t
h
e
sev
e
n-l
e
vel
C
S
I
.
The se
ve
n-
le
ve
l and the l
o
ad
current
wave
f
o
rm
s are prese
n
t
e
d i
n
t
h
i
s
fi
g
u
re
. Fi
g
u
re
9 sh
o
w
s t
h
e DC
cur
r
e
n
t
wave
f
o
rm
s fl
owi
n
g t
h
r
o
ug
h t
h
e 6
0
0
-
H sm
oot
hi
ng
i
n
d
u
ct
o
r
s L
1,
L
2
and L
3
.
T
h
e
am
pl
i
t
udes
of
t
h
e sm
oot
hi
ng
i
n
d
u
ct
o
r
c
u
rre
n
t
s are
wel
l
bal
a
nce
d
fo
r al
l
sm
oot
hi
ng
i
n
duct
o
rs
I
L1
, I
L2
and
I
L3
[8
]
.
Fi
gu
re
8.
Se
ve
n-l
e
vel
P
W
M
c
u
r
r
ent
a
n
d l
o
a
d
cu
rre
nt
wave
f
o
rm
s
Fi
gu
re
9.
DC
c
u
r
r
ent
wa
vef
o
r
m
s of sm
oot
hi
ng
in
du
ctor
s
Fi
gu
re
1
0
. E
x
p
e
ri
m
e
nt
al
t
e
st
r
e
sul
t
s
o
f
l
o
ad
c
u
r
r
ent
a
n
d se
ve
n l
e
vel
P
W
M
c
u
r
r
ent
wa
vef
o
r
m
s
Furt
herm
ore,
i
n o
r
de
r t
o
v
e
ri
fy
t
h
e p
r
o
pos
ed se
ve
n-l
e
vel
C
S
I c
o
n
f
i
g
urat
i
o
ns e
x
peri
m
e
nt
al
l
y
,
l
a
bo
rat
o
ry
pr
ot
ot
y
p
es se
ven
-
l
e
vel
C
S
I wa
s
con
s
t
r
uc
ted
wi
th
IXFK90
N30
power MOSFET
s in
series with
DSE
I
1
2
0
-
0
6A
fast reco
very
d
i
odes
.
T
h
e
lo
w
o
n
-resistance
(R
DS
on
) of th
e
p
o
w
e
r
MO
S
F
E
T
s
,
an
d low for
w
ar
d
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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S
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8-8
6
9
4
A Si
ngle-Phase
Multilevel Current-Sour
ce
Converter using H-Bri
d
ge an
d DC
Current M
o
dules
(Suroso)
17
1
vol
t
a
ge
d
r
o
p
(
V
F
) of
diodes
are chose
n
i
n
order to m
i
nimize
th
e cond
u
c
tio
n
lo
sses.
The on
-resistan
c
e o
f
th
e
po
we
r M
O
SF
ET
s a
n
d
t
h
e
f
o
rwa
r
d
-
vol
t
a
ge
dr
o
p
of
t
h
e
di
ode
s a
r
e
3
3
m
Ω
an
d 1.
3
V
(
ma
x
), re
spectiv
ely
.
Th
e
i
m
p
l
e
m
en
ted
circu
it sp
ecificatio
n
s
are id
en
tical with th
e
c
o
m
put
er si
m
u
l
a
ti
on
pa
ram
e
t
e
rs i
n
T
a
bl
e
3
.
T
h
e DC
resi
st
ance
of t
h
e 0
.
6 m
H
sm
oot
hi
n
g
i
n
du
ct
ors i
s
2
6
.
5
m
Ω
obtaine
d from
m
easurem
e
n
t.
T
h
e control
circuits
were bu
ilt u
s
ing
an
alog
circu
i
ts.
Th
e op
to-iso
lato
r b
a
se
d
g
a
te d
r
i
v
er ci
rcu
i
ts are
u
s
ed
in th
e
p
r
o
t
o
t
yp
es.
Fi
gu
re 1
0
s
h
o
w
s t
h
e e
xpe
ri
m
e
nt
al
wavef
o
rm
s of t
h
e sev
e
n-l
e
vel
C
S
I, i
.
e., s
h
o
w
i
n
g t
h
e l
o
ad c
u
r
r
ent
and
P
W
M
s
e
v
e
n-l
e
vel
c
u
r
r
en
t
wa
vef
o
rm
s at
m
odul
at
i
o
n
i
n
dex
of
0
.
9
5
.
A
s
can
be see
n
i
n
t
h
e
fi
gu
re,
a
l
o
w
d
i
sto
r
ted
si
n
u
s
o
i
d
a
l lo
ad
curren
t wav
e
form
i
s
ob
tain
ed
after filtering
b
y
a
sm
a
ll 5
-
F filter cap
acito
r
.
4. CO
N
C
L
U
S
I
ON
In
th
is p
a
p
e
r,
a n
o
v
e
l circu
it co
nfigu
r
ation
o
f
m
u
ltilev
e
l c
u
rren
t
-
source in
v
e
rter h
a
s b
e
en
presen
ted
and ve
ri
fi
ed.
In
th
is
n
e
w t
o
po
log
y
, a three-lev
e
l H-b
r
i
d
ge CS
I is conn
ected
with
a si
ng
le or m
o
re curren
t
-
m
odules to ge
nerate the m
u
ltilevel output current
wave
fo
rm
. In orde
r
to cont
rol
the interm
ediate
current
lev
e
ls and
to red
u
c
e th
e size
o
f
t
h
e indu
ctors u
s
ed
in
th
e
m
u
l
tilev
e
l CSI, chop
p
e
r circuits with
propo
rtio
n
a
l
in
teg
r
al
(PI) cu
rren
t
regu
lator are im
p
l
e
m
e
n
ted
t
o
g
e
n
e
rat
e
t
h
e DC
c
u
rre
nt
-s
ou
rces
of
t
h
e i
n
vert
e
r
.
Us
i
ng t
h
e
prese
n
t
e
d
t
o
po
l
ogy
a
nd
fr
om
t
e
st
resul
t
s
of
t
h
e se
ven
-
l
e
v
e
l
C
S
I, a si
nus
oi
dal
l
o
a
d
c
u
r
r
e
nt
wa
vef
o
rm
s wi
t
h
l
e
ss di
st
o
r
t
i
o
n,
l
e
ss c
o
m
pone
nt
s
of
i
n
vert
er
,
sm
all
e
r si
ze o
f
sm
oot
hi
ng
i
n
duct
o
rs
a
n
d
wi
t
h
l
o
wer
i
n
du
c
t
or’
s
conduction los
s
es can be
achi
e
ved.
REFERE
NC
ES
[1]
Bai ZH,
et al
.
Conform
a
tion o
f
m
u
ltil
evel
curr
ent source
conv
erter
topolog
ies
using the dual
i
t
y
pr
inciple.
IE
EE
Trans. on Power
Electronics
. 200
8; 23: 2260-226
7.
[2]
Xu D,
et al
.
A medium voltage AC drive w
ith par
allel cu
rrent sou
r
ce in
verters for
high power app
lication
. Proc. o
f
IEEE PES Conf
erence. 2005; 22
77-2283.
[3]
Suroso,
et
al.
Multil
evel
curr
ent
waveform
gene
ration using
in
d
u
ctor
cel
ls and
H-bridge curr
ent
source inv
e
rt
er
,
”
IEEE Tr
ansactio
ns on Power
Electronics. 2012
; 2
7
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[4]
Antune
s FLM,
e
t
al
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ica
tion
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e
ner
a
li
zed
curren
t
m
u
lti
lev
e
l
cel
l to
curr
ent
s
ource
invert
ers
.
IE
EE T
r
ans. o
n
Power Electroni
c. 1999
; 46
: 31-
38.
[5]
Bao
J
Y
, et al
.
P
WM contr
o
l
of
a
5-le
vel
s
i
ngl
e-p
has
e cur
r
e
nt-s
ou
r
ce in
ver
t
e
r
with
contr
o
l
l
ed
inter
m
ediate
DC lin
k
c
u
rre
nt
. Pro
c
. of
IEEE PES Conf
erence. 2006; 16
33-1638.
[6]
McGrath BP,
e
t
al
. Natur
a
l
c
u
rrent ba
lan
c
in
g of m
u
ltic
ell
current sour
ce
invert
er.
I
E
EE
Trans. on Power
Electronics
. 200
8; 23: 1239-124
6.
[7]
Vazquez N, e
t
a
l
. A differen
t
m
u
ltil
evel
curren
t
source invert
er
.
IEEE Trans. on Industrial Ele
c
tr
onics
.
2010; 57:
2623-2632.
[8]
S
u
ros
o
, et al.
New H-Bridge Multilevel Current
-source PWM Inverter with Re
duced Switching Devices Count.
Proc.
of IEEE IPEC
2
010 confer
ence.
2010; 1228-123
5.
[9]
Barbosa PG, et al. Boost curren
t
m
u
ltilevel inver
t
er and
its appl
ication on single p
h
ase grid connected photovolt
a
i
c
sy
s
t
e
m
.
I
E
EE Trans. on
Power Electronics
. 2006; 21; 1116-1124
.
[10]
Suroso,
et al
.
H-Bridge Based Five-Level Current-Source I
nverter for Grid Connected Photovotaic Power
Conditioner
.
TELKOMNIKA
. 20
13; 11; 489-494.
[11]
Suroso,
et al. Com
m
on-E
m
itter
Topolog
y
of Multilev
e
l Curr
en
t-Source Pulse Width Modulation Invert
er with
Chopper based
DC-Current Sou
r
ces.
IET
Pow
e
r
Ele
c
tronics
. 201
1; 4: 759-765.
[12]
Li RIH, et al.
An activ
e
modulation
techniqu
e for single-
phase grid conn
ected CSI.
IEEE
Trans. on Power
Electronics
. 200
7; 22; 1373-138
0.
[13]
Wu B. High
Power Converters
and AC Driv
es.
IEEE Pre
ss,
New J
e
rse
y.
2006
.
[14]
Kwak S, et
al.
Multilev
e
l
conv
erter
topolog
y
u
s
ing two t
y
p
e
s o
f
curren
t
-source
invert
ers.
I
EEE
Trans. on Inductry
Applica
tions
. 20
06; 42; 1558-15
64.
BIOGRAP
HI
ES
OF AUTH
ORS
Suroso
received
the B.
Eng. d
e
gree in
ele
c
tr
ica
l
engin
eering
,
fr
om
Gadjah M
a
da Univers
i
t
y
,
Indonesia
in 20
01, and
the M. Eng. degree
in
electr
i
cal
and
electro
n
i
cs en
gineer
ing from
Nagaoka Univer
sity
of
Technolog
y
,
Japan in 2
008. He was a re
search
student at
electr
ical
engineering dep
a
rtment,
Tok
y
o University
, Jap
a
n from 2005 to 2
006. He earned
the Ph.D degree
in energ
y
and en
vironment engin
eering d
e
partment
, Nagaok
a University
of Techn
o
log
y
, Japan
in
2011.He was a v
i
siting r
e
search
er at electri
c
al
an
d electroni
cs en
gineer
ing dep
a
rt
m
e
nt, Shizuoka
University
, Japan from 2009 to
2011.
Curren
t
ly
, He is an
assistant
prof
essor at
department of
electrical engin
e
ering, Jenderal
Soedirman Univ
ersity
, Purwoker
t
o, Cen
t
ral Java, Indonesia.His
research
in
terest
includ
es power
converters, and
its application
in r
e
newable
energ
y
conversion
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-86
94
I
J
PED
S
Vo
l. 4
,
No
. 2
,
Jun
e
2
014
:
16
5
–
17
2
17
2
Toshihiko Noguchi
was born in 1959. He received the B
.
Eng. degree in
electr
ical eng
i
neering
from
Nago
y
a
In
stitute of
Te
chn
o
log
y
, Nago
ya
,
Japa
n, and
the
M. Eng.
and D.
Eng. degr
ees in
electrical and
electronics s
y
stems engineer
in
g from Nagao
k
a University
of Technolog
y
,
Nagaoka, Japan
,
in 1982, 1986, 1996, r
e
spectiv
ely
.
In 1982
, h
e
join
ed Toshib
a Corporation,
Tok
y
o
,
J
a
p
a
n.
He was
a L
ectu
r
er at
Gifu Nat
i
onal Col
l
ege
of
Techno
log
y
, Gif
u
, J
a
pan
,
from
1991 to 1993 and a Resear
ch Associate in electri
cal
and electronics s
y
stems engineering at
Nagaoka Univer
sity
of
Technolog
y
from 1994 to
1995. He
was an Associate Professor at
Nagaoka Univer
sity
of Technolo
g
y
from 1996 to
2009. He has been a Professor at Shizuoka
University
sin
c
e
2009.
His resear
ch in
terests
ar
e s
t
atic power
conv
erters
and motor
drives.
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