Internati
o
nal
Journal of P
o
wer Elect
roni
cs an
d
Drive
S
y
ste
m
(I
JPE
D
S)
Vol
.
7
,
No
. 2,
J
une
2
0
1
6
,
pp
. 58
3~
60
0
I
S
SN
: 208
8-8
6
9
4
5
83
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
Analysis and Implementation
of
a High B
o
ost Rati
o DC-DC
Converter for Minimizing Co
mmutation Torque Ripple in
Brushless DC Motor
M.
Sen
t
hil Raja, B.
Geethal
a
ksh
m
i
Departement of
Electrical and
Electron
i
cs Eng
i
neering, Pondich
er
r
y
Engin
eerin
g College, India
Article Info
A
B
STRAC
T
Article histo
r
y:
Received Nov 21, 2015
Rev
i
sed
May 13
, 20
16
Accepted
May 31, 2016
Brushless dc m
o
tor stil
l suffer
s
from
com
m
u
t
a
tion
torque r
i
p
p
le,
which
prim
aril
y d
e
pen
d
s on transi
ent
l
i
ne
current
in
th
e com
m
u
tation
i
n
terva
l
.
In
order to con
t
rol
the in
coming an
d outgoing phas
e
curren
t
s to ch
ange at the
same rate durin
g commutation,
this pa
per
presents a novel high
boost ratio
DC-DC circuit
topolog
y
in
the front end of
the inver
t
er
. With a suitab
l
e
closed
loop control
scheme, the propos
ed high b
oost ratio DC-D
C converter
is operated with
two differen
t
duty
r
a
tios one dur
ing commutation
period and
the other during
non commutation period.
The
cause of commutation r
i
pple
is
anal
yz
ed
, and
the wa
y to
adju
s
t
the dut
y r
a
tio
for obtain
i
ng the
des
i
red d
c
link voltage is
introduced
in d
e
tail. Finally
, simu
lation and
experimental
results show tha
t
, com
p
ar
ed with
the
existing
dc–
d
c conv
erte
r top
o
logies,
the
proposed method can obtain th
e desired
voltag
e
much faster and minimize
commutation tor
que ripp
le
more
efficiently
.
Keyword:
Brushl
ess dc
motor (BLDC)
C
o
m
m
ut
at
i
on
DC-link
v
o
ltage
straterg
y
Hi
g
h
bo
ost
rat
i
o
co
n
v
ert
e
r
Torque ripple
Copyright ©
201
6 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
:
M. Sen
t
h
il Raja
Depa
rtem
ent of Electrical a
n
d
El
ect
ro
ni
cs E
n
gi
nee
r
i
n
g,
Pondicherr
y
Eng
i
neer
ing
Colleg
e
,
Po
ndi
c
h
er
ry
1
4
,
I
ndi
a.
Em
a
il: m
u
th
ap
p
a
.sen
th
il@yah
o
o
.
co
m
1.
INTRODUCTION
B
r
us
hl
ess
dc
m
o
t
o
rs (B
LDC
M
) p
o
ssessi
ng
sim
p
l
e
st
ruct
u
r
e, hi
gh
p
o
w
e
r
den
s
i
t
y
, hi
g
h
t
o
r
q
ue/
c
ur
re
nt
rat
i
o
,
ro
b
u
st
ne
ss, an
d
bet
t
e
r
dy
nam
i
cs have
bee
n
wi
del
y
used in all kinds of areas
, s
u
c
h
as electric
vehicles,
robo
tics, sm
al
l actu
a
to
rs, i
n
du
stry
a
n
d aut
o
m
o
tive electronics [1]–[3].
T
h
e
perform
a
nce of s
u
ch m
o
tors
has
been si
gni
fi
cant
l
y
im
prove
d
due t
o
t
h
e g
r
eat
devel
o
pm
ent
of
p
o
we
r c
o
n
v
e
r
t
e
rs, m
a
gnet
i
c
per
f
o
r
m
a
nce o
f
magnets, a
n
d
m
o
tion c
ontrol
technology
in recent years [4]–[6].
Howe
ver,
c
o
mm
utation t
o
rque ri
pple has
always bee
n
one m
a
jor
factor in pre
v
enting
BLDCM fr
om
achi
e
vi
n
g
hi
g
h
per
f
o
rm
ance.
The
ca
uses for torque
r
i
pp
le in
BLDCM ar
e th
e imp
e
rf
ectio
n
o
f
m
o
to
r
d
e
sign an
d m
a
n
u
f
acture, non
-
i
d
eal EMF and
un
equal cu
rr
en
t
shari
n
g
bet
w
e
e
n t
h
e
p
h
ases
d
u
ri
ng
com
m
u
t
a
t
i
on [
7
]
and
[
8
]
.
Si
nce
t
o
r
q
ue sm
oot
hne
ss i
s
a
n
e
ssent
i
a
l
req
u
i
r
em
ent
fo
r suc
h
hi
g
h
-
p
e
r
f
o
rm
ance ap
p
l
i
cat
i
ons, a wi
de va
ri
et
y
of t
echni
que
s ha
v
e
been
p
r
o
p
o
s
e
d by
m
a
ny
researc
h
ers
du
ri
n
g
t
h
e
past
t
w
o
deca
d
e
s t
o
m
i
nim
i
se
t
h
e t
o
rq
ue
ri
p
p
l
e [9]
–
[
14]
.
In
recent years
,
m
u
ltilevel inverter
s ha
ve gained m
u
ch attention i
n
the a
pplication area
s of BL
DC
m
o
t
o
r dri
v
es
[
21]
. T
h
e p
r
obl
em
of im
perfe
ct
i
on i
n
t
h
e m
o
t
o
r desi
gn i
s
ove
rc
om
e
i
n
[13]
an
d [
1
4]
, whe
r
ei
n
[1
3]
su
ggest
s
appl
i
cat
i
o
n o
f
Tag
u
chi
m
e
t
hod i
n
desi
gni
n
g
t
h
e sh
ape
of
perm
anent
m
a
gnet
s
a
nd i
n
[1
4]
a
segm
ent
e
d pe
r
m
anent
m
a
gnet
st
ruct
u
r
e i
s
pr
o
pose
d
whi
c
h si
g
n
i
f
i
c
a
n
t
l
y
red
u
ce
d t
h
e
com
m
ut
ati
on t
o
r
q
ue
ri
p
p
l
e
. S
o
m
e
r
e
searche
s
[
3
]
,
[1
5]
–
[1
7]
i
n
t
r
o
d
u
ced
n
ovel
po
we
r co
n
v
ert
e
r t
o
pol
ogi
es a
nd
P
W
M
t
e
c
h
ni
q
u
es
for co
n
t
ro
lling
th
e inp
u
t
vo
ltag
e
o
f
t
h
e BLDCM d
r
iv
e.
In
[3
], th
e i
n
v
e
rter is op
erated
in
1
2
0
m
o
d
e
fo
r
lo
w
e
r
spee
d range of the
m
achine and in
180
m
ode fo
r hi
ghe
r speed r
a
n
g
e t
h
e
r
eby
o
p
t
i
m
i
z
i
ng t
h
e com
m
utat
i
on
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:2088
-86
94
I
J
PED
S
Vo
l.
7
,
No
.
2
,
Jun
e
2
016
:
58
3 – 60
0
58
4
t
o
r
que ri
ppl
e
.
I
n
[
15]
, a b
u
ck
con
v
e
r
t
e
r i
s
us
ed f
o
r re
d
u
ci
n
g
t
h
e com
m
ut
at
i
on t
o
r
q
ue ri
p
p
l
e
at
l
o
w spe
e
d. I
n
[1
6]
, a
su
pe
rl
i
f
t
L
uo
co
n
v
ert
e
r
i
s
pl
ace
d at
t
h
e i
n
p
u
t
st
a
g
e
o
f
t
h
e
i
n
vert
e
r
t
o
pr
o
duce
de
si
red
dc
l
i
n
k
vol
t
a
ge,
and t
h
e structure works m
o
re
eff
ectiv
ely und
er
h
i
gh-
sp
eed o
p
e
r
a
ting
co
ndition, com
p
ared wit
h
the m
e
thod
pr
o
pose
d
i
n
[
1
5]
. H
o
w
e
ve
r t
h
e
m
e
t
hods
pr
o
pos
ed i
n
[
15]
a
nd
[
16]
s
u
f
f
er
fr
om
sl
ow v
o
l
t
a
ge ad
j
u
st
m
e
nt, an
d
therefore, they
can on
ly ach
iev
e
satisfactory to
rq
u
e
pu
lsatio
n
supp
re
s
s
i
o
n i
n
l
o
w-
or
hi
g
h
-
s
pee
d
re
gi
o
n
s.
Thi
s
p
r
ob
lem is al
l
e
v
i
ated
in
[1
7], [
20] where
by a SEPIC conve
rter wit
h
a switch over
MOSFET is used t
o
im
pl
em
ent
t
h
e dc l
i
nk v
o
l
t
a
ge ad
ju
st
m
e
nt
. Ho
weve
r, t
h
e
po
wer c
o
n
v
er
t
e
r req
u
i
r
es a
very
hi
gh
di
re
ct
dc
v
o
ltag
e
as inpu
t du
r
i
n
g
non-
co
mm
u
t
atio
n
p
e
r
i
o
d
and
an
o
t
h
e
r
bo
osted
v
o
ltag
e
boosted
thr
oug
h
SEPI
C
con
v
e
r
t
e
r
du
ri
ng
t
h
e c
o
m
m
utat
i
on
peri
od
. F
o
r
suc
h
dc
v
o
l
t
a
ge a
d
j
u
st
m
e
nt
, t
h
i
s
ci
rc
ui
t
re
qui
res a
n
a
ddi
t
i
onal
swi
t
c
h sel
ect
i
o
n ci
rc
ui
t
f
o
r
sw
i
t
c
hi
ng
fr
om
n
o
n
com
m
ut
at
i
on
peri
od
t
o
c
o
m
m
u
t
a
t
i
on peri
od
.
Use o
f
l
o
w
vo
l
t
a
ge i
n
p
u
t
sou
r
ce i
s
pre
f
er
re
d o
v
er a hi
gh
vol
t
a
ge s
o
urce
, and
hen
ce i
n
t
h
e prese
n
t
pape
r
a
hi
gh b
oost
rat
i
o
dc – dc
co
n
v
ert
e
r (
H
B
D
C
)
[
18]
t
h
at
requi
res ve
r
y
l
o
w dc
vol
t
a
ge at
t
h
e i
n
p
u
t
si
de i
s
u
s
ed
. Of th
e en
tire h
i
gh
-bo
o
s
t ratio
n
o
n
-iso
l
a
ted
DC–D
C co
nv
erter to
po
l
o
g
i
es pub
lish
e
d
[19
]
, a co
m
b
in
atio
n
of
fl
y
-
back
a
n
d
bo
ost
c
o
nve
r
t
er i
s
hi
g
h
l
y
ef
fi
ci
ent
as
it i
n
creases t
h
e
b
oost ratio
w
ith l
o
wer cost
and
greater
efficien
cy [1
8
]
. Besid
e
s, in
the p
r
o
p
o
s
ed
to
po
log
y
, th
e
n
e
ed
of an
add
ition
a
l switch
selectio
n
circu
it as u
s
ed
in
[17
]
is ov
erco
m
e
b
y
o
p
e
ratin
g
th
e co
nv
erter with
t
w
o
d
i
fferen
t
du
ty ratio
s on
e
d
u
rin
g
no
n-co
mmu
tation
peri
od
, a
n
d
t
h
e
ot
he
r
d
u
ri
n
g
c
o
m
m
ut
at
i
on
pe
ri
o
d
.
Si
m
u
l
a
t
i
on
an
d e
x
peri
m
e
nt
al
resul
t
s
sho
w
t
h
at
c
o
m
p
are
d
wi
t
h
com
m
on t
h
e dc–
d
c co
nve
rt
er t
o
p
o
l
o
gi
es, t
h
e p
r
op
ose
d
co
nve
rt
er
ope
rat
e
d
wi
t
h
sui
t
a
bl
e
dut
y
rat
i
o
co
n
t
ro
l can
redu
ce co
mm
u
t
at
i
o
n torqu
e
ripp
le sign
ifican
tly.
2.
PROP
OSE
D
HIGH
BOOS
T
RATI
O
DC
-D
C CO
NVE
RTER A
N
D
I
T
S
OPE
RATI
O
N
In t
h
e
pr
o
pos
ed
hi
g
h
-
b
oost
rat
i
o
DC
-
D
C
co
nve
rt
er
[
1
8]
sh
o
w
n
i
n
Fi
gu
re.
1
,
HT
i
s
a hy
b
r
i
d
tran
sform
e
r with
tu
rn
s ratio
1: n
,
M
1
is th
e
MOSFET switch
carryin
g
cu
rren
t I
s1
and C
in
i
s
t
h
e i
nput
ca
p
aci
t
o
r.
A co
upl
e
d
i
n
d
u
ct
o
r
has bee
n
em
pl
oy
ed i
n
t
h
e pri
m
ary
si
de of t
h
e t
r
ans
f
orm
e
r t
o
pro
v
i
d
e a hi
g
h
st
ep-
up rat
i
o
an
d to
redu
ce t
h
e switch
v
o
l
t
a
g
e
stress su
b
s
tan
tially. D
1
i
s
t
h
e cl
am
pi
ng
di
o
d
e,
w
h
i
c
h
pr
o
v
i
d
es c
u
r
r
e
n
t
pat
h
for the leaka
g
e inductance
of th
e hy
bri
d
t
r
ansf
o
r
m
e
r whe
n
M
1
is OFF.
C
c
is the cla
m
ping capacitor whic
h
captures the leakage e
n
ergy from
th
e h
y
b
r
id tran
sfo
r
m
e
r an
d
tran
sfers it to
th
e reso
n
a
n
t
cap
acito
r C
r
, which
is
connected in s
e
ries with
th
e hyb
r
i
d tr
ansfo
r
mer
.
Fi
gu
r
e
1.
C
o
nfi
g
u
r
at
i
on
o
f
B
L
DC
M
dri
v
i
n
g sy
st
em
wi
t
h
a
hi
g
h
b
oost
rat
i
o
dc
-
d
c c
o
n
v
e
r
t
e
r
The
reso
na
nt c
i
rcuit com
p
rise
s o
f
C
c
, C
r
, L
r
and
D
r
whe
r
eL
r
i
s
t
h
e res
o
na
n
t
i
n
d
u
ct
or
w
h
i
c
h
ope
rat
e
s
i
n
t
h
e reso
nant
m
ode and D
r
i
s
t
h
e reso
nant
di
o
d
e w
h
i
c
h i
s
use
d
t
o
pr
ovi
d
e
a uni
-di
r
ect
i
o
nal
cur
r
ent
fl
o
w
pat
h
fo
r t
h
e o
p
e
r
at
i
on
of t
h
e res
o
n
a
nt
circuit. T
h
e conduction
of D
r
is d
e
term
i
n
ed
b
y
th
e
state of the active
switch
M
1
, D
o
is th
e
ou
tpu
t
d
i
od
e si
milar to
th
e cou
p
l
ed
-i
n
d
u
c
tor bo
ost conv
ert
e
r, C
0
is
the
output ca
pacitor
and R
L
is th
e resistiv
e lo
ad. I
cr
is th
e cu
rren
t of th
e reso
n
a
n
t
cap
a
cito
r C
r
, I
in
is
th
e prim
ary si
d
e
cu
rren
t
o
f
h
ybrid
trans
f
orm
e
r and
I
o
i
s
t
h
e
o
u
t
p
ut
di
ode
cu
rre
n
t
.
The stea
dy state topology stages
of
t
h
e
propos
ed DC-DC conve
r
te
r for one s
w
itching c
y
cle can be
gi
ve
n i
n
fi
ve st
ages.
The
ex
pl
anat
i
o
n
o
f
eac
h
m
ode i
s
as
fol
l
ows:
Mo
de 1:
(
t
0
< t < t
1
)
The e
qui
val
e
nt
ci
rcui
t
co
rres
p
on
di
n
g
t
o
t
h
i
s
m
ode i
s
sho
w
n
i
n
Fi
g
u
r
e.
2 i
n
whi
c
h t
h
e
M
O
SFE
T M
1
i
s
swi
t
c
he
d O
N
, t
h
e
p
r
i
m
ary si
de v
o
l
t
a
ge
o
f
hy
br
id transfo
r
m
e
r is ch
arged
to
i
n
pu
t vo
l
t
ag
e V
in
. C
r
is
charge
d
by
C
c
, whi
c
h
was cha
r
ge
d i
n
a pre
v
i
o
us c
y
cl
e. The i
n
p
u
t
voltage is reflected on the s
econda
r
y side of the
h
ybrid
tran
sform
e
r b
y
n
-
times (n
V
in
),
d
u
e
to
th
e m
a
g
n
e
tic co
up
lin
g be
tween t
h
e
pri
m
ary and
sec
o
nda
r
y
wind
ing
s
. Th
e en
erg
y
st
o
r
ed
in
th
e cap
acitor C
c
is tran
sferred to
C
r
, wh
ich
in-turn is tran
sferred
t
o
th
e lo
ad
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
PED
S
I
S
SN
:
208
8-8
6
9
4
An
al
ysi
s
a
n
d
I
m
pl
e
m
ent
a
t
i
o
n
of
a
Hi
g
h
B
o
o
s
t
Rat
i
o
DC
-
D
C
C
onve
r
t
e
r f
o
r Mi
ni
mi
zi
ng
…
(
M
. Se
nt
hi
l
Raj
a
)
58
5
w
h
e
n
M
O
S
F
E
T
i
s
t
u
r
n
e
d
O
F
F
.
T
h
e
c
u
r
r
e
n
t
i
n
M
O
S
F
E
T
M
1
i
s
t
h
e
sum
of
t
h
e
res
o
nant
cu
rre
nt
I
r
an
d
lin
ear
m
a
gnet
i
s
i
n
g
i
n
duct
o
r
cu
rre
nt
.
Fi
gu
re 2.
M
o
d
e
1 Eq
ui
val
e
nt
ci
rcui
t
Mo
de 2:
(
t
1
< t < t
2
)
In
th
is m
o
d
e
, th
e MOSFET M
1
i
s
t
u
rne
d
O
FF as depi
ct
ed
i
n
Fi
gure
3(a
)
and t
h
ere
f
ore
t
h
e cl
am
pi
ng
di
o
d
e D
1
i
s
t
u
rne
d
O
N
by
t
h
e l
eaka
g
e en
ergy
st
o
r
ed i
n
t
h
e hy
bri
d
t
r
a
n
sf
orm
e
r du
ri
n
g
m
ode 1. C
l
am
pi
ng
capacitor C
c
is
ch
arg
e
d
d
u
ring th
is
p
e
riod
. This cau
ses th
e
vo
ltag
e
to be clam
p
e
d
Fi
gu
re 3(a
)
.
Eq
ui
val
e
nt
ci
rcui
t
M
o
d
e
2
Mo
de 3:
(
t
2
< t < t
3
)
The clam
ping capacitor C
c
i
s
charge
d t
o
v
o
l
t
a
ge t
h
at
can fo
rwa
r
d bi
as t
h
e o
u
t
p
ut
di
o
d
e
D
0
. So the
energy stored i
n
the m
a
gnetising i
n
ductor a
n
d capacit
o
r
(C
r
) is being tra
n
s
f
erred t
o
the load. T
h
e clam
p diode
D
1
con
tinu
e
s t
o
co
ndu
ct wh
ile C
c
rem
a
in
s ch
arg
e
d
.
Th
is
pro
cess con
tinues un
til C
c
get
s
di
sc
har
g
ed
a
n
d
t
h
e
cor
r
es
po
n
d
i
n
g
equi
val
e
nt
ci
rc
ui
t
i
s
sh
o
w
n
i
n
Fi
gu
re
3(
b
)
.
Fi
gu
re 3(
b
)
.
E
q
ui
val
e
nt
ci
rcui
t
M
o
d
e
3
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I
S
SN
:2088
-86
94
I
J
PED
S
Vo
l.
7
,
No
.
2
,
Jun
e
2
016
:
58
3 – 60
0
58
6
Mo
de 4:
(
t
3
< t < t
4
)
Whe
n
C
c
get
s
di
schar
g
e
d
, t
h
e di
o
d
e
D
1
is reverse base
d and as a res
u
lt the energy s
t
ore
d
in the
m
a
gnet
i
s
i
ng i
n
duct
o
r
of t
h
e h
y
b
ri
d t
r
a
n
s
f
o
r
m
e
r and t
h
e ca
paci
t
o
r C
r
is sim
u
l
t
an
eo
usly tran
sferred
to
th
e lo
ad
.
Du
ri
n
g
t
h
e st
e
a
dy
st
at
e
ope
ra
t
i
on,
t
h
e c
h
a
r
g
e
t
h
r
o
ug
h
C
r
m
u
st satisfy th
e ch
arg
e
b
a
lance. It
is
o
b
s
erved
t
h
at
the capacitor operates in hy
brid-switchi
ng
m
ode (i.e.)
by
havi
ng c
h
a
r
ge
d i
n
reso
na
nt
m
ode and
di
sc
har
g
e
d
lin
early and
is
clear fro
m
th
e
eq
u
i
v
a
len
t
circu
it is sh
own
in Figu
re 3©.
Fi
gu
re 3(c
)
.
Eq
ui
val
e
nt
ci
rcui
t
M
o
d
e
4
Mo
de 5:
(
t
4
< t < t
0
)
T
h
e
MO
S
F
ET M
1
is tu
rn
ed ON at ti
m
e
t
4
and
t
h
e c
o
r
r
e
sp
on
di
n
g
e
q
u
i
val
e
nt
ci
rc
ui
t
i
s
gi
ve
n i
n
Fi
gu
re
4.
T
h
e
out
put
di
ode
c
u
r
r
ent
I
0
con
tinu
e
s t
o
flow
for a sh
ort tim
e d
u
e
to th
e leak
ag
e effect
of th
e h
ybrid
trans
f
orm
e
r.
The diode D
0
will b
e
rev
e
rse
b
i
ased
at tim
e t
0
; the
next cycle
starts.
Fi
gu
re
4.
Eq
ui
val
e
nt
ci
rc
ui
t
M
ode
5
3.
AN
ALY
S
IS
O
F
C
O
M
M
U
TATIO
N
TO
R
Q
UE
RIPPLE
IN BL
DC
M
BLD
C
M conven
tio
n
a
lly
o
p
e
r
a
tes in two
p
h
a
se
1
2
0
◦
(electrical) conducting m
ode, and t
h
is
con
d
u
ct
i
ng m
ode i
n
cl
u
d
es a com
m
ut
ati
on r
e
gi
o
n
an
d a n
o
n
com
m
ut
at
i
on regi
o
n
. T
h
i
s
p
a
per f
o
c
u
ses o
n
t
h
e
com
m
ut
ati
on r
e
gi
o
n
, ai
m
i
ng at
red
u
ci
n
g
co
m
m
u
t
a
t
i
on t
o
r
q
u
e
ripp
le. For th
e curren
t
analysis, it is ass
u
m
e
d
th
at th
e m
o
to
r is u
n
s
at
u
r
ated
, arm
a
tu
re reactio
n
is n
e
g
lig
i
b
le, stato
r
wi
nd
ing
is symme
trical, th
e resistan
ces
and i
n
d
u
ct
a
n
ce
s of t
h
e m
o
t
o
r
wi
n
d
i
n
gs a
r
e
con
s
t
a
nt
an
d t
h
e m
o
t
o
r ex
hi
bi
t
s
n
o
co
g
g
i
n
g t
o
rq
ue.
The
vol
t
a
ge
equat
i
o
n f
o
r
t
h
e
B
L
DC
m
o
t
o
r
can be re
prese
n
t
e
d by
(1
) [8]
and
[
1
7]
di
a
vi
R
L
e
v
aa
a
n
o
dt
di
b
vi
R
L
e
v
no
bb
b
dt
di
c
vi
R
L
e
v
cc
c
n
o
dt
(1
)
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
PED
S
I
S
SN
:
208
8-8
6
9
4
An
al
ysi
s
a
n
d
I
m
pl
e
m
ent
a
t
i
o
n
of
a
Hi
g
h
B
o
o
s
t
Rat
i
o
DC
-
D
C
C
onve
r
t
e
r f
o
r Mi
ni
mi
zi
ng
…
(
M
. Se
nt
hi
l
Raj
a
)
58
7
Whe
r
e
,a
n
d
vv
v
ac
b
are th
e p
h
a
se
vo
ltag
e
s o
f
t
h
e th
ree
wind
ing
s
of B
L
DC m
o
to
r,
,a
n
d
ii
i
ac
b
are the phase
currents
,
,a
n
d
ee
e
ac
b
are the tra
p
ezoi
d
al
back em
f,
L
LM
s
is the e
qui
valent inductance
of t
h
e phase
wind
ing
s
and
R is th
e
resist
ance of
the phas
e
windings
.
The t
o
r
que
eq
u
a
t
i
on
of
t
h
e B
L
DC
M
[
17]
i
s
()
ei
e
i
e
i
aa
c
c
bb
T
e
r
(2)
Whe
r
e
r
is the
s
p
eed of t
h
e m
o
tor.
The prese
n
ce of
inducta
nce
el
e
m
ents
in
th
e
ph
ase
wind
ing
s
resu
lts in
a trap
ezo
i
d
al curren
t
wav
e
fo
rm
instead of rectangular one.
T
h
i
s
l
eads t
o
t
o
r
que
ri
p
p
l
e
d
u
ri
ng c
o
m
m
ut
at
i
o
n pe
ri
o
d
s. B
e
f
o
re t
h
e com
m
ut
at
i
o
n
interval, t
h
e current fl
ows through
phase
-
A to phase
-
C
as shown in Fi
g
u
re 5
.
(a). After th
e co
mm
u
t
atio
n
i
n
t
e
rval
,
t
h
e c
u
rre
nt
fl
ows
t
h
r
o
u
g
h
pha
se-B
t
o
pha
se C
whi
c
h i
s
s
h
ow
n i
n
F
i
gu
re
5(
b)
.
Fi
gu
re
5(a
)
C
o
nd
uct
i
n
g st
a
g
e
of
p
h
ase
-
A
an
d
pha
se-C
Fi
gu
re
5(
b
)
C
o
nd
uct
i
n
g st
a
g
e
of
p
h
ase
-
B
a
n
d
phase-C
Fo
r t
h
is an
alysis, th
e co
mm
u
t
atio
n
o
f
th
e cu
rren
t fro
m
p
h
ase A to
ph
ase B is co
n
s
id
ered. Th
en
th
e
in
itial
vol
t
a
ge
val
u
es
at
t
h
e be
gi
nni
n
g
of
com
m
ut
at
ion
can
be
d
r
a
w
n as
f
o
l
l
o
w
s
:
At th
e i
n
stan
t
of co
mm
u
t
a
tio
n
,
=0;
=
;
=0
= 0;
=
;
=-
(3
)
App
l
yin
g
th
e i
n
itial co
nd
itio
ns g
i
v
e
n in
(3) t
o
(1) an
d (2
),
0
0
di
a
iR
L
E
v
am
n
o
dt
di
b
Vi
R
L
E
v
mn
o
dc
b
dt
di
c
iR
L
E
v
cm
n
o
dt
(4)
2
0
EI
mm
T
e
r
(5)
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:2088
-86
94
I
J
PED
S
Vo
l.
7
,
No
.
2
,
Jun
e
2
016
:
58
3 – 60
0
58
8
W
i
t
h
the
phase
resistance
ne
glected in
(4
),
th
en the
rate
o
f
c
h
an
ge
o
f
phase
curre
nts ca
n
be expres
sed as
2
3
2
3
4
3
VE
di
m
dc
a
dt
L
VE
di
m
dc
b
dt
L
VE
di
m
dc
c
dt
L
(6
)
During
co
mm
u
t
atio
n
th
e to
rque is ob
tain
ed
as
4
2
3
VE
E
m
md
c
TI
t
em
L
r
(7
)
For derivi
ng the rise tim
e of Phase
B c
u
rre
nt
consider the
Figure. 6a
Fi
gu
re 6(a
)
.
> 4
Fi
gu
re 6(
.
< 4
2
3
VE
di
m
dc
b
dt
L
2
03
1
3
2
1
VE
IL
I
m
dc
mm
t
tL
VE
m
dc
(8
)
2
3
VE
di
m
dc
a
dt
L
2
03
2
32
2
VE
IL
I
m
dc
mm
t
tL
V
E
m
dc
(
9
)
R
e
lated tor
q
ue
rip
p
le is gi
ve
n
by
0
4
3
dc
m
ee
e
VE
TTT
t
L
(1
0)
From
(10), it is clear that i
n
order to
obtain z
e
ro torque,
40
4
VE
V
E
mm
dc
d
c
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
PEDS I
S
SN:
208
8-8
6
9
4
An
alysis a
n
d
I
m
ple
m
ent
a
tion
of
a
Hig
h
B
o
o
s
t Ratio
DC
-
D
C
C
onve
r
ter fo
r M
i
nimizi
ng
…
(
M
. Se
nthil
Raja)
58
9
It is kn
ow
n f
r
om
the afore
m
entioned a
n
a
l
y
s
is that by
injectin
g a dc
voltage
of
4
m
E
du
r
i
ng
com
m
utation,
it is possible t
o
re
d
u
ce com
m
u
tation tor
q
u
e
ripple to a l
a
rge
r
exte
nt.
Hence i
n
the
prese
n
t
pape
r,
by
ad
o
p
ting p
r
ope
r c
o
ntr
o
l strategy
,
the d
u
ty
ratio
of t
h
e HB
DC
conve
r
ter is adj
u
sted such t
h
at the
co
nv
er
ter
p
r
ov
id
es a d
c
vo
ltage of
4
E
m
du
rin
g
the
pe
rio
d
of
com
m
utation.
4.
DESIG
N
OF HIGH
BOOS
T
RATI
O
DC
-D
C CO
NVE
RTER
F
O
R
B
L
DC M
O
TO
R DRI
VE
The HBDC
is a
com
b
ination of flybac
k
c
o
nverter
an
d
bo
ost co
nv
er
ter
as h
i
gh
ligh
t
ed
in Figu
r
e
7
(
a)
an
d 7(b
)
r
e
sp
ectiv
ely.
Figu
re
7(a
)
.
Hi
ghlig
htin
g t
h
e
Fly
b
ack c
o
nve
rter
Figu
re 7(
b
)
. Hi
ghlig
htin
g
t
h
e B
oost
c
o
nve
rte
r
The
b
oost c
o
n
v
erter
o
u
tp
ut is
store
d
i
n
the
c
l
am
ping ca
paci
tor C
c
and
i
s
exp
r
e
s
se
d a
s
i
n
(1
1)
1
V
in
V
C
c
D
(1
1)
W
h
en
th
e
sw
it
c
h
i
s
O
N
,
b
o
t
h
V
Cc
a
n
d th
e trans
f
orm
e
r out
put
(leaka
g
e inducta
n
ce)
are re
sponsibl
e for
char
gin
g
of
the
res
ona
nt ca
pa
citor C
r
.
The
v
o
ltage ac
ros
s
t
h
e
reso
na
nt ca
pacitor
is gi
ve
n
by
(
1
2)
c
cr
in
C
Vn
V
V
(1
2)
Substituting (11) in
(12)
gives
1
1
Vn
V
cr
in
D
(1
3)
The rem
a
ining setup
is
that of a
flybac
k
co
nver
t
er
an
d its outp
u
t
is
g
i
v
e
n
by [
2
0
]
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN:2088
-86
94
I
J
PEDS Vo
l.
7
,
No
.
2
,
Jun
e
2
016
:
58
3 – 60
0
59
0
1
1
nD
VV
in
fo
D
(1
4)
The
ove
rall o
u
tp
ut is the s
u
m
of the
out
p
u
t o
f
the
fly
b
a
c
k co
n
v
erte
r a
nd t
h
e v
o
ltage
acros
s the r
e
s
ona
nt
capacitor whic
h is i
n
se
ries with
it. The
effe
ctive DC
output is
1
1
nD
VV
V
in
Cr
dc
D
(1
5)
Substituting (13) in
(15)
2
1
n
VV
in
dc
D
Hence
the
duty ratio is
12
V
in
Dn
V
dc
(1
6)
As pe
r (
1
0
)
,
d
u
ri
ng c
o
m
m
utation it is desired to ha
ve
4
dc
m
VE
. He
nce d
u
ri
ng c
o
m
m
u
tation the duty
ratio
of
HB
DC
s
h
o
u
l
d be
ad
justed
as
12
4
V
in
Dn
E
m
(1
7)
5.
C
O
N
T
RO
L OF
H
I
GH
BOOS
T RA
TI
O
DC
-D
C
CONVER
TER
FED
BLD
C
M
O
TOR
DR
IV
E
Figu
re
8 s
h
ows
the
bloc
k
diag
ram
of the cl
os
ed lo
o
p
c
ont
rol
sy
stem
of t
h
e
B
L
DC
m
o
tor
.
Figu
re
8.
C
o
ntr
o
l sy
stem
of th
e B
L
DC
m
o
tor
A thr
e
e-
ph
ase
m
o
to
r
r
a
ted 160W,
4
8
Vd
c,
30
00
rp
m
is f
e
d b
y
a HB
DC an
d six step vo
ltag
e so
ur
ce
inve
rter. T
h
e inve
rter gates si
gnals are
pr
od
uced
by
d
ecodi
ng the
Hall Effect signals
of the m
o
tor. The
three-
pha
se
out
put
o
f
the
in
verte
r
i
s
ap
plied t
o
t
h
e B
L
DC
m
o
to
r stato
r
win
d
in
gs.
Tw
o
co
ntr
o
l lo
o
p
s is
use
d
.
The
inne
r loop synchronizes the inve
rter
gates signals
with
the help of Hall
sensors.
T
h
e
out
er loop c
o
m
p
ares the
stator c
u
r
r
ent
of t
h
e m
o
tor a
nd
re
gulates t
o
va
ry
th
e o
u
tput of
t
h
e hig
h
b
o
o
st
ratio DC
-
D
C
C
o
nve
rter by
suitably adjusting the
duty
ratio
of the C
o
nve
r
ter.
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I
J
PEDS I
S
SN:
208
8-8
6
9
4
An
alysis a
n
d
I
m
ple
m
ent
a
tion
of
a
Hig
h
B
o
o
s
t Ratio
DC
-
D
C
C
onve
r
ter fo
r M
i
nimizi
ng
…
(
M
. Se
nthil
Raja)
59
1
As m
e
ntioned earlier, the torque ripples are pr
om
inent duri
ng the c
o
m
m
utation p
e
rio
d
. A hi
gh
voltage i
n
put (
4
E
m
) is to be i
n
j
ecte
d
to t
h
e
inve
rter during th
at
peri
od [
1
6]
.
I
n
stead of
usin
g
tw
o diff
erent
conve
r
ters
or a
n
additional voltage so
urce as give
n in
[17], it is advanta
g
eous to
vary the out
put
of t
h
e
DC-
DC converter
by suitably a
d
justing the
d
u
ty
ratio
of t
h
e co
nve
rter.
He
nce
an a
rra
ngem
e
nt is re
qui
red t
o
d
e
tect
the com
m
utation
pe
rio
d
of
the B
L
DC
m
o
tor
.
Fi
gu
re
9 s
h
o
w
s t
h
e c
o
ntrol a
rra
n
g
em
ent f
o
r
detectin
g th
e
com
m
utation p
e
rio
d
.
Figure
9. Sc
he
m
a
tic represe
n
ting
Di
gital signal controller
functionalities
Signals
from
t
h
e Hall sensors and t
h
e stator phase
curre
nt
s are give
n as i
n
put to the c
o
ntrol schem
e
whe
r
ein the first stage a curre
n
t to vo
ltage c
o
nve
r
ter is use
d
.
An
ope
rational am
plifier i
n
com
p
arator
m
ode is
use
d
with
on
e
of the i
n
p
u
ts
gr
o
u
n
d
e
d
. O
n
l
y
duri
n
g com
m
u
tation pe
rio
d
tw
o o
f
the
p
h
ases
have t
h
e
sam
e
pola
r
ity (owi
ng to the
prese
n
ce of a cr
oss-over
betwee
n two
phases in e
ither
polarity),
whic
h can
be detected
using AND gat
e
s. This si
gnal
is used t
o
adjust the duty
ratio of the c
o
nve
rter. The
di
gital
logic circ
uit used in
the c
ontr
o
l sc
hem
e
generate
s H
I
G
H
o
u
tp
u
t
whe
n
com
m
u
tation occ
u
rs and L
O
W
when non-c
om
m
u
ta
tion
peri
od
.
6.
SIM
U
LATI
O
N
AN
D
E
X
PE
RIME
NTAL
RESULTS
In
or
de
r to as
sess the
per
f
o
r
m
a
nce of
the
sy
stem
with a particula
r
f
o
c
u
s
on c
o
m
m
utation to
rq
u
e
rip
p
le, a M
a
tlab-Sim
u
link ba
sed m
odel in tim
e
dom
ain
has been
devel
ope
d. T
h
e o
u
t
put pe
rf
o
r
m
a
nces are
cur
r
ent,
v
o
ltag
e
, bac
k
- EM
F
,
and
the t
o
r
q
ue
variatio
n
un
de
r
steady
-
state
o
p
eratin
g c
o
ndit
i
ons
.
The sim
u
lated and e
x
perim
e
ntal wavef
o
rm
of t
h
e B
L
DC
M
drive sy
ste
m
with the p
r
o
pos
ed
HB
DC
con
v
e
r
ter at
1
5
0
0
rpm
is sh
ow
n i
n
Fi
gu
re
1
0
to
Fig
u
re
13
. T
h
e sim
u
lated o
u
tp
ut
vo
ltage o
f
the
hi
gh
b
o
o
st
r
a
tio
DC-DC co
nv
er
ter
is shown in Figu
r
e
10
(
a
)
and
th
e
c
o
r
r
es
po
n
d
in
g e
xpe
rim
e
ntal wavef
o
rm
is sh
o
w
n
in
Figu
re 1
0
(
c)
. I
t
can be see
n
that Vdc =
4E
m
unde
r
the
app
r
o
p
r
iate input
voltage
o
f
the inve
rter
d
u
ri
ng
co
mm
u
t
at
io
n
per
i
od
,
th
e tor
q
u
e
r
i
pp
le du
r
i
ng
co
mm
u
t
at
io
n is pr
opo
r
tion
a
l to
|V
d
c
−
4E
m
|, Vdc is cl
oser to
4E m
torque
pulsation is significantly reduc
ed. T
h
e sim
u
la
ted Inve
rter line to line voltage is shown i
n
Figure.
10
(
b
) a
n
d t
h
e c
o
r
r
es
po
n
d
in
g e
xpe
rim
e
ntal wavef
o
rm
is sh
o
w
n in Figu
r
e
10
(d
).
I
t
can
b
e
seen
th
at th
e inp
u
t
of
the inve
rter
dc
link v
o
ltage
d
u
ri
ng c
o
m
m
utation pe
rio
d
th
e rising a
n
d fa
lling p
o
rtio
n o
f
co
rres
p
on
din
g
line
voltage
is af
fec
t
ed by
spi
k
es.
The duty ratio of HB
DC is ap
propriately controlled in orde
r
to inject a Vdc of 4Em
during
com
m
utation a
n
ad
ditional
vo
ltage of
1
60
v
o
lts is inject
ed..
I
n
d
c
link
durin
g
ch
opp
ing
per
i
od
th
e r
i
sing
and
falling pe
rio
d
of c
o
r
r
esp
o
ndi
ng line v
o
ltage
is affected
by
spikes
. The si
m
u
lated and e
xpe
rim
e
ntal results fo
r
stator curre
nt of BLDC m
o
tor are show
n in Figure 11 and
Figure 12 respec
tively. In the
s
e, the places
m
a
rked
with circle shows that the curren
t slo
p
es o
f
incom
i
ng and
out
goi
ng
pha
s
e
s du
rin
g
com
m
utation thr
o
u
gh t
h
e
recom
m
ended
m
e
thod
are
fa
r clo
s
er
tha
n
t
hos
e
witho
u
t
com
m
utation
[
17]
.
T
h
e s
p
ike
s
o
f
w
h
ich c
u
rre
nts
occu
rri
ng
at th
e en
d
of
com
m
u
tation
get sm
oot
h, a
n
d the
c
u
rrent is m
u
ch
closer t
o
a
rect
angle.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN:2088
-86
94
I
J
PEDS Vo
l.
7
,
No
.
2
,
Jun
e
2
016
:
58
3 – 60
0
59
2
(a)
(
b
)
(c)
(d
)
Figu
re
1
0
. T
h
e
sim
u
lated and
expe
ri
m
e
ntal
wave
f
o
rm
of t
h
e B
L
DC
M
d
r
i
v
e sy
stem
; (a).
Sim
u
lated res
u
lt for
out
put v
o
ltage of
the hig
h
b
o
o
s
t
ratio DC
-
D
C
co
nve
rter.
(b)
Si
m
u
lated result for Inverter line to line
volt
a
ge.
(c) Ex
perim
e
ntal
result fo
r out
put v
o
ltage
of
the
hig
h
bo
ost
r
a
tio DC
-
D
C
c
o
nve
rter.
(
d
)
E
x
perim
e
ntal result
for
Inverte
r
line to line
voltage
.
Figu
re
1
1
Stat
or
cu
rre
nt
of al
l the three
pha
ses of BL
DC m
o
tor
Evaluation Warning : The document was created with Spire.PDF for Python.