Internati
o
nal
Journal of Ele
c
trical
and Computer
Engineering
(IJE
CE)
V
o
l.
6, N
o
. 4
,
A
ugu
st
2016
, pp
. 14
56
~
1
469
I
S
SN
: 208
8-8
7
0
8
,
D
O
I
:
10.115
91
/ij
ece.v6
i
4.9
156
1
456
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
/
IJECE
Active LC Clamp dv/dt Filter
for
Vo
ltage
Re
fle
c
tio
n
due
to
Long Cable in Induction Motor Drives
Mini R
1
, Manjiri
Jo
shi
2
, B.
Hariram Satheesh
3
, Dinesh M. N.
4
1
VTU Res
ear
ch
s
c
holar
and F
a
cu
lt
y of
El
ec
tric
al
and E
l
ec
troni
cs
departm
e
nt
, Am
rita
Vis
h
waVid
y
apee
tham
Bang
a
l
ore
Cam
pus, Am
rita Universit
y
,
Ind
i
a
2
Ele
c
tri
cal
and
E
l
ec
tronics
d
e
par
t
m
e
nt, Am
rita
Vi
s
h
waVid
y
ap
eeth
a
m
Bangalor
e
C
a
m
pus
, Am
rita
Univers
i
t
y
,
Indi
a
3
A
BB, G
I
S
L
, B
a
ngalore
, Ind
i
a
4
Facult
y
of
Ele
c
t
r
ica
l
and
E
l
e
c
tro
n
ics dep
a
rtm
e
nt
, R V Colleg
e of
Engineering, Bangalore, Ind
i
a
Article Info
A
B
STRAC
T
Article histo
r
y:
Received Oct 7, 2015
Rev
i
sed
Jun
23,
201
6
Accepte
d J
u
l
6, 2016
This
pap
e
r pr
es
ents
an
a
c
tiv
e L
C
cl
am
ped dv/d
t
fil
t
er
to m
i
t
i
ga
te
the ov
e
r
voltag
e
s
appeari
ng acros
s
the motor term
inals
.
The over volt
a
g
e
s
at m
o
tor
terminal is due to voltage ref
l
ection
eff
ect of long motor cable connected
between high
frequency
PWM invert
er having high dv/dt switching
waveforms and
ac motor dr
ives. The vo
lt
age r
e
flection due to f
a
st switchin
g
trans
i
en
ts
can b
e
reduc
ed b
y
in
cr
eas
ing th
e ris
e
ti
m
e
and fal
l
tim
e
of inver
t
er
output voltag
e
pulses. The m
o
st
com
m
only
av
ail
a
ble m
itiga
ting t
echniqu
e is
a passive dv/dt f
ilter b
e
twe
e
n inv
e
rter
a
nd cab
le
. Since, si
ze,
cost
and losses
of passive LC d
v
/dt filter
is more, an
ac
tive dv
/d
t filt
ering
techn
i
que is used
to redu
ce
over
volt
a
ge
at
m
o
tor t
e
rm
inals.
Active
LC
cl
a
m
p filter
i
ng
techn
i
que used
h
e
re
consists of a sma
ll LC f
ilter
designed for
a single motor
cable leng
th which can b
e
used f
o
r an
y
leng
ths of cable up to 100
0m only
b
y
changing th
e act
ive control of th
e P
W
M
pulses t
o
achiev
e
the desired voltag
e
slope during vo
ltag
e
transition
period.
The bas
i
c prin
cipl
e of
act
ive dv/d
t
filer used
here
is to cha
r
ge
an
d discharge
the
capa
c
i
t
or in
th
e fil
t
er wi
th
modified PWM pulses to incr
ease th
e
rise time and f
a
ll
time of output
voltag
e
pulses
without
an
y
ex
tr
a dev
i
ces
to h
a
n
d
le
the
transient response of
the LC fi
lt
er.
Detai
l
ed inv
e
sti
g
ation is c
a
rri
e
d
out b
y
sim
u
l
a
tion using
MATLAB-Sim
u
link softwar
e
wit
h
ac
tive
control
of common LC
clamp dv/d
t
filter suitabl
e f
o
r various cab
l
e
lengths rang
i
ng from
100 m to 1000 m
.
Comparative an
aly
s
is is done with act
ive dv/dt filter design
ed with a
com
m
on LC clam
p filter
and act
ive LC
clam
p dv/dt fil
t
er d
e
signed for
various cab
le lengths and also
with di
ode
clam
ped passive dv/dt filter.
The
results proves the effe
ctiv
eness of the activ
e
com
m
on LC dv/dt filt
er to
m
itigate th
e ov
er
volt
a
ges
at m
o
t
o
r term
inal for
cable leng
ths up
t
o
1000m
.
Keyword:
Activ
e LC Clam
p
d
v
/
d
t
Filter
I
ndu
ctio
n Mo
t
o
r
Lo
ng
C
a
bl
e
Vo
ltag
e
Reflectio
n
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
:
Min
i
R,
Depa
rtem
ent of Electrical and
Electronics
E
ngi
neeri
n
g,
Am
ri
t
a
Vi
shwa
Vi
dy
apeet
ham
,
B
a
n
g
al
ore
C
a
m
pus,
Carm
alram
,
Of
f Sa
rja
p
ur
Roa
d
, Ba
n
g
alo
r
e-56
003
5, K
a
rn
at
aka, India.
Em
a
il: min
i
_
s
uj
ith
@b
lr.am
r
it
a.edu
,
m
i
n
i
r_
su
j
ithr@yah
o
o
.
co
m
1.
INTRODUCTION
Pul
s
e
wi
dt
h
M
o
d
u
l
a
t
e
d
IGB
T
i
nve
rt
ers a
r
e
wi
del
y
use
d
i
n
vari
a
b
l
e
s
p
eed
IM
D
.
T
h
e
hi
g
h
s
w
i
t
c
hi
n
g
sp
eed
s
o
f
IGB
T
with
sh
ort rise ti
me an
d
fall ti
me
lead
s
to
h
i
gh
dv
/d
t in
th
e in
v
e
rter ou
t
p
u
t
vo
ltag
e
pu
l
s
es. In
m
a
ny industria
l applications inductio
n m
o
tor and inve
rter
are placed at
differe
nt locations and he
nce
needs
long ca
bles t
o
connect t
h
em
. The
high
dv
/d
t
of i
n
v
e
rter
ou
tp
u
t
pu
lses
with steep rise tim
e
th
rou
gh lon
g
cab
l
es
r
e
su
lts in
v
o
ltag
e
dou
b
ling
at m
o
to
r
ter
m
in
al
d
u
e
to
vo
ltag
e
r
e
f
l
ectio
n
ph
en
o
m
en
a [
1
]-[3
].
Th
e
o
v
e
r
vo
ltag
e
s
ap
p
e
aring
across th
e m
o
to
r term
in
al stresses th
e m
o
to
r in
sulatio
n
and
fi
n
a
lly lead
s to
m
o
t
o
r i
n
su
lation
failu
re.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
ECE
I
S
SN
:
208
8-8
7
0
8
Active LC Clamp d
v
/
d
t Filter fo
r Vo
ltag
e
Reflectio
n
du
e t
o
Lon
g
Cab
l
e in
Indu
ctio
n .... (
M
in
i R)
1
457
Acco
r
d
i
n
g t
o
NEM
A
st
a
nda
rd
dv/
dt
of t
h
e
pul
ses
has t
o
be l
i
m
i
t
e
d t
o
less t
h
an
50
0
V
/
µ
s i
n
46
0V cl
ass of
m
o
to
rs. The voltag
e
reflection is d
e
p
e
nd
en
t on
rise ti
m
e
o
f
i
n
v
e
rter
ou
tpu
t
p
u
l
ses, th
e leng
th
o
f
th
e cab
l
e u
s
ed
fo
r i
n
t
e
rc
on
ne
ct
i
ng i
n
vert
er
and m
o
t
o
r an
d
sur
g
e im
peda
nce o
f
m
o
t
o
r and ca
bl
e. If t
h
e pr
opa
gat
i
o
n t
i
m
e
i
s
m
o
re th
an
h
a
lf o
f
rise tim
e, t
h
en
vo
ltag
e
reflectio
n
at
m
o
to
r term
in
al o
ccu
rs
with
p
e
ak v
o
ltag
e
of twi
ce th
e
am
pl
i
t
ude of
i
n
put
v
o
l
t
a
ge [1]
.
The m
o
st
co
m
m
onl
y
used
m
i
ti
gat
i
ng t
ech
ni
q
u
e f
o
r
v
o
l
t
a
ge d
o
ubl
i
n
g
d
u
e t
o
vol
t
a
ge
r
e
fl
ect
i
on i
s
a
p
a
ssiv
e
d
v
/
d
t
filter b
e
tween
t
h
e i
n
v
e
rter and
cab
l
e
[4
]-[8
]
.
Th
e p
a
ssi
v
e
d
v
/
d
t
filter con
s
istin
g o
f
indu
ctor,
cap
acito
r and
resisto
r
will increase th
e rise ti
m
e
an
d
redu
ce th
e
dv
/d
t
g
r
ad
ien
t
o
f
i
n
v
e
rter ou
tpu
t
v
o
ltag
e
p
u
l
se.
Bu
t p
a
ssiv
e
filters wit
h
d
a
m
p
in
g
resisto
r
s h
a
v
e
d
r
awb
a
ck
of large po
wer l
o
ss.
A
d
i
od
e clam
p
e
d
LC
filter conn
ected
to th
e n
e
u
t
ral o
f
DC
lin
k vo
ltag
e
is t
h
e
best op
tio
n in term
s o
f
reliab
ility an
d
p
o
wer lo
sses
[9
]-[11
]. B
u
t st
ill larg
e filter size, lo
sses in
t
h
e syste
m
an
d
hig
h
co
st are t
h
e draw
b
a
ck
s of p
a
ssiv
e
filters.
Th
is
p
a
p
e
r emp
l
o
y
s activ
e LC cla
m
p
filterin
g
techn
i
qu
e t
o
m
itig
ate o
v
e
r vo
ltag
e
s at m
o
to
r term
in
als
by
l
i
m
i
ti
ng d
v
/
dt
of i
n
vert
er
out
p
u
t
p
u
l
s
es
by
i
n
c
r
easi
n
g
ri
se t
i
m
e
of i
nve
rt
er
o
u
t
p
ut
vol
t
a
ge p
u
l
s
e
s
. Thi
s
m
e
thod is the joi
n
t effect of
sm
all
passive LC diode cla
m
ped filter and ac
tive control of this LC filter by
m
o
d
i
fied
PWM p
u
l
ses. Th
e filter v
a
lu
es are d
e
si
g
n
ed
b
a
sed
o
n
t
h
e requ
ired
vo
ltag
e
t
r
an
sition
tim
e
an
d
t
h
e
filter p
e
ak
cu
rren
t
and
reson
a
n
ce freq
u
e
n
c
y
wh
ich
is se
lected
well ab
ov
e
th
e switch
i
n
g
frequ
e
n
c
y, h
e
n
c
e th
e
size o
f
th
e indu
ctor b
e
co
m
e
s
s
m
all an
d
th
e filter size is red
u
c
ed
. Th
e
req
u
i
red
v
o
ltage rise ti
m
e
to
av
o
i
d
v
o
ltag
e
reflect
io
n
d
e
p
e
nd
s
on
th
e leng
th
of th
e cab
l
e. In activ
e d
v
/
d
t
d
i
od
e clam
p
e
d
LC filter th
e
activ
e
filterin
g
is ach
i
ev
ed b
y
t
h
e com
b
in
ed
effort o
f
LC filte
r and
its activ
e co
ntro
l b
y
ch
arg
i
ng
an
d
d
i
sch
a
rg
i
n
g th
e
cap
acito
r of
filter to
m
a
in
tain
th
e m
o
to
r term
in
al vo
ltag
e
equ
a
l to d
c
lin
k
vo
ltag
e
. Th
e m
a
in
adv
a
n
t
ag
e of th
is
m
e
thod is
sm
all filter that re
duces t
h
e size a
n
d cost
of f
ilter. The control
of LC
filter is done
by alteri
ng P
W
M
seq
u
ence
w
h
i
c
h
does
n
o
t
re
qui
re a
n
y
ext
r
a de
vi
ces o
r
har
d
ware set
u
p,
he
nce si
m
p
l
e
, co
nve
ni
ent
an
d
econom
i
cal. Sim
u
la
tion is ca
rried out i
n
M
A
TL
AB-
Simu
lin
k p
l
atform to
v
a
lid
ate
t
h
e pe
rf
orm
a
nce o
f
t
h
e
activ
e dv
/d
t
filter d
e
sign
ed fo
r v
a
riou
s
cab
le leng
th
s with correspo
n
d
i
ng
m
o
d
i
fi
ed
PWM
pu
lses.
To
stan
d
a
rd
ize t
h
e filter size a commo
n
filter is d
e
sign
ed
wh
ich
is su
itab
l
e for all th
e cab
le l
e
n
g
t
h
s
rang
ing fro
m
10
0m
t
o
100
0
m
and o
v
er
vo
l
t
a
ge i
ssue i
s
reduce
d
by
onl
y
vary
i
ng t
h
e soft
ware
base
d
swi
t
c
hi
n
g
t
i
m
e
s an
d
cor
r
ect
i
on
p
u
l
s
e cont
rol
of
P
W
M
.
A pe
rf
orm
a
nce com
p
ari
s
on i
s
ca
rr
i
e
d o
u
t
wi
t
h
bot
h ap
pr
oac
h
es an
d
o
b
s
erv
e
d th
at t
h
e co
mm
o
n
filter is m
u
ch
smaller th
an th
e passiv
e
filter and
is su
itab
l
e
for m
i
t
i
g
a
tin
g
v
o
ltage
reflection
effect d
u
e
to v
a
rious cab
le len
g
t
h
s
and
effec
tiv
eness of activ
e co
n
t
ro
l is v
a
lid
ated
.
A
p
a
ssi
v
e
filter
had
bee
n
desi
g
n
ed
an
d
val
i
d
a
t
ed t
h
e
pe
rf
or
m
a
nce f
o
r
cabl
e
l
e
ngt
hs
ra
ngi
ng
f
r
om
10
0
m
t
o
1
0
0
0
m
and
wa
s
r
e
po
r
t
ed
in
th
e p
r
ev
iou
s
wo
rk
[
1
0
]
.
2.
VOLTAGE REFLECTION THEORY
The IGBT inverter output voltage pulses wi
th shor
t rise tim
e travels along the long ca
ble to reach
th
e m
o
to
r termin
als. Th
ese
pu
lses acts lik
e
trav
ellin
g
waves th
rou
g
h
tran
sm
issio
n
lin
e. Th
e m
a
j
o
r cau
s
es
of
ove
r
vol
t
a
ge
s
at
m
o
t
o
r t
e
rm
inal
are
fast
ri
s
e
t
i
m
e
of i
n
v
e
r
t
er o
u
t
p
ut
v
o
l
t
a
ge, l
e
ngt
h o
f
cabl
e
an
d i
m
pedanc
e
mis
m
a
t
ch between m
o
tor a
n
d
cable characteristics.
The m
o
tor impeda
nce is
m
u
ch highe
r
than the ch
aracteri
s
tic im
pedance of cable and hence
due t
o
im
pedance m
i
smatch the travelling wa
ve
reflects b
ack
. If th
e
p
r
o
p
a
g
a
tion ti
m
e
is
m
o
re t
h
an h
a
lf of rise ti
m
e
(
, the
m
o
tor term
inal voltage will shoot up to doubl
e the
am
plitude of
inpu
t voltage
[2],[12],[13]
.Pro
pag
a
tion
time (
) i
s
t
h
e t
i
m
e
t
a
ken by
t
h
e pul
se t
o
reac
h t
h
e ot
her e
n
d
of t
h
e ca
bl
e.
R
i
se t
i
m
e
(
) is th
e
t
i
m
e
t
a
ken by
t
h
e a
ppl
i
e
d
v
o
l
t
age t
o
reac
h a
p
pr
o
x
i
m
at
el
y
90% o
f
t
h
e
de
si
re
d m
a
gni
t
u
d
e
of
v
o
l
t
a
ge.
The am
pl
i
t
ude
o
f
refl
ect
ed
v
o
l
t
a
ge
wa
ve
d
e
pen
d
s
o
n
v
o
ltage reflectio
n co-e
fficient o
f
m
o
tor
and
i
s
gi
ve
n
by
eq
uat
i
o
n
(
1
)
,
(1
)
whe
r
e,
i
s
m
o
tor c
h
ara
c
t
e
ri
st
i
c
im
pedance a
nd
is cable c
h
aracteristic im
peda
nce.
The
peak m
o
t
o
r
termin
al v
o
ltage
) gi
ve
n by
eq
uat
i
o
n
(
2
)
,
(2)
The re
flection
co-e
fficient
va
ries with t
h
e si
ze of t
h
e m
o
tor and its val
u
e
reduces as t
h
e
size of
m
o
to
r in
creases. Th
e literature reports th
at th
e reflectio
n co
-efficien
t
valu
e rang
es
b
e
tween
0.65
to 0
.
95.
Hence
,
o
v
er
vo
l
t
a
ges appea
r
at
m
o
t
o
r t
e
r
m
i
n
al
due t
o
v
o
l
t
a
ge refl
ect
i
o
n p
h
en
om
ena. Th
e ove
r vol
t
a
ges
can be
min
i
mized
b
y
i
n
creasi
n
g th
e
risin
g
and
falling
tim
es o
f
ou
tpu
t
vo
ltag
e
pu
lses.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-87
08
I
J
ECE
Vo
l. 6
,
N
o
. 4
,
Au
gu
st 2
016
:
14
56
–
1
469
1
458
3.
DESIGN OF ACTIVE
L
C
CLAMP DV/DT
FILTER
3.
1.
Desi
gn
o
f
ac
ti
ve L
C
cl
am
p
f
i
l
t
er
Th
e b
a
sic p
r
i
n
cip
l
e
of o
p
e
rat
i
o
n
of
activ
e dv
/d
t filter
is
to
g
e
n
e
rate
t
h
e req
u
i
red
rising
an
d
falling
vol
t
a
ge sl
ope
s by
i
n
creasi
ng t
h
e ri
se an
d fal
l
t
i
m
e
s as shown i
n
Fi
gu
re 1
.
It
i
s
achi
e
ved
by
t
h
e sel
ect
ion
o
f
sm
a
ll LC
filter
an
d
its activ
e
co
n
t
ro
l b
y
ch
arg
i
ng
and
d
i
scharg
i
n
g
th
e filter cap
acito
r to
i
n
crease th
e
rise ti
me
and
fal
l
t
i
m
e
of t
h
e i
nve
rt
er
out
put
v
o
l
t
a
ge
.
The char
gi
n
g
and
di
scha
rgi
n
g t
i
m
i
ng seque
nce i
s
cont
r
o
l
l
ed by
m
o
d
i
fyin
g
th
e
PW
M
pu
lses.
Th
e i
n
du
ctor i
n
th
e LC
filte
r will li
m
it th
e ch
arg
i
ng
and
disch
a
rg
ing
cu
rren
t
of
th
e inv
e
rter and
h
e
n
c
e co
n
t
rol th
e filter
p
e
ak
cu
rren
t
.
Th
e m
a
in
ad
v
a
n
t
ag
e
o
f
activ
e
dv
/d
t is t
h
at th
e filter
inductor value
is very sm
a
ll because
in active dv/dt filter, t
h
e output tran
sient voltage sl
ope
depe
nds only on
th
e LC co
n
s
tan
t
o
f
th
e circu
it. Th
e filter v
a
lu
es are d
e
signed
b
a
sed
on
the req
u
i
red
rise ti
me o
f
th
e in
v
e
rter
o
u
t
p
u
t
vo
ltag
e
an
d th
e
filter
peak
cu
rren
t. The filter is
d
e
sign
ed at h
i
g
h
reso
n
a
n
t
freq
u
e
n
c
y to
redu
ce th
e size
of
filter and the ne
utral
of t
h
e filter is connecte
d
to t
h
e
m
i
dpoint
of
DC link
which hel
p
s to
re
duce the
co
mm
o
n
m
o
d
e
vo
ltag
e
s
o
f
IMD.
Diod
e clam
p
i
n
g
is prov
i
d
ed to
clam
p
th
e
o
s
cillatio
n
s
o
f
LC filter t
o
th
e d
c
l
i
nk val
u
e.
Fig
u
re
1
.
Active LC clam
p
d
v
/d
t filter topo
log
y
Active LC
clam
p dv/dt
filter com
pone
nt
va
lues are
designed
base
d
on ri
se tim
e
of i
n
verter
out
put
vol
t
a
ge
(
).
Propagation tim
e increase
s
as t
h
e
lengt
h
of the
c
a
ble inc
r
eases
and is
ba
sed on equ
a
tio
n (3
) [4
],
(
3
)
whe
r
e,
cabl
e
l
e
ngt
h,
pr
o
p
agat
i
n
g
wa
ve
vel
o
ci
t
y
.
The
vel
o
ci
t
y
of
pr
o
p
agat
i
o
n
of
p
u
l
s
e t
h
r
o
ug
h t
h
e ca
bl
e
i
s
consi
d
ere
d
app
r
oxi
m
a
t
e
ly
hal
f
o
f
t
h
e
v
e
lo
city of light. Rise ti
m
e
(
)
of
u
n
d
er
dam
p
ed sec
o
nd
o
r
de
r sy
st
em
i
s
gi
ven
by
eq
uat
i
o
n
(4
)
[1
4]
,
(
4
)
whe
r
e (
ξ
) - d
a
m
p
in
g
factor wh
ich
is
con
s
id
ered
n
e
g
lig
ib
le. Hen
c
e, rise
time
(5)
6
whe
r
e
i
s
t
h
e
u
ndam
p
ed
nat
u
r
a
l
fre
que
ncy
.
Th
e LC filter i
s
d
e
sign
ed
at reson
a
n
ce
frequen
c
y wh
ich
is
ab
ov
e th
e
swit
ch
ing
frequ
e
n
c
y th
at h
e
lp
s
to
redu
ce th
e si
ze of filter. At
reson
a
n
ce, en
erg
y
st
o
r
ed
i
n
ind
u
c
t
o
r is equ
a
l
to
en
erg
y
stored
in cap
acit
o
r
[1
5
]
,
)
(
7
)
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
ECE
I
S
SN
:
208
8-8
7
0
8
Active LC Clamp d
v
/
d
t Filter fo
r Vo
ltag
e
Reflectio
n
du
e t
o
Lon
g
Cab
l
e in
Indu
ctio
n .... (
M
in
i R)
1
459
and
whe
r
e,
- filter
p
eak curren
t
,
- DC
link
v
o
ltage.
Th
e filter co
mp
on
en
t v
a
lues
are d
e
si
g
n
e
d
based
o
n
abo
v
e
eq
u
a
tion
s
. But fo
r i
n
du
stry
ap
p
lication
d
e
sign
ing
cu
st
o
m
ized
filter fo
r
d
i
fferen
t cab
l
e leng
th
s is
no
t adv
i
sab
l
e. Hen
ce, i
n
th
is
p
a
p
e
r
sm
al
l LC filter is
designe
d
which can be
use
d
for cable lengths ra
ngi
ng
fr
om
100m
to 1000m
by active
cont
rol of LC filter by
app
r
op
ri
at
e sel
ect
i
on
of
t
h
e m
odi
fi
ed
P
W
M
pul
ses
.
Fro
m
equ
a
tio
n
(3) to (7
) co
m
m
o
n
filter co
m
p
on
en
t v
a
l
u
es
are
d
e
sign
ed as fo
llo
ws,
= 6
.
7*
10
-6
sec
To
a
v
oi
d v
o
l
t
a
ge refl
ect
i
o
n p
h
en
om
ena
ri
se t
i
m
e
(
) of
out
put voltage is
se
lected above t
w
ice the
wave
p
r
opa
gat
i
o
n
t
i
m
e
.
Using
equ
a
tio
n (5
)
= 17
9.18
r
a
d
/
sec
Using
equ
a
tio
n (6
)
= 31
.1
4*1
0
-12
(8)
Fo
r
filter p
e
ak
cu
rren
t
of
7A
an
d D
C
lin
k voltag
e
of
o
f
565V
u
s
ing
equ
a
tio
n (7
),
56
5
2
)
65
14
(9
)
Th
e m
i
n
i
m
u
m
in
du
ctor and
cap
acito
r
v
a
lu
es requ
ired
fo
r t
h
e activ
e LC clam
p
d
v
/
d
t
filter is o
b
t
ain
e
d
fro
m
eq
u
a
tion
s
(8
) and
(9) and
filter in
du
ct
or
v
a
lu
e is
45
0
µ
H an
d cap
acit
o
r
v
a
lu
e is
68
.95
n
F.
3.
2.
Acti
ve c
o
ntr
o
l
of LC clam
p
dv/dt filter
LC
circu
it
d
e
sig
n
e
d
with
n
e
g
lig
ib
le d
a
m
p
i
n
g
g
i
v
e
s o
s
cillatio
n
s
wh
en
su
bj
ected
to
i
n
v
e
rter
ou
tpu
t
step
vo
ltag
e
s
an
d
th
e
p
e
ak
a
m
p
litu
d
e
o
f
o
s
cillatio
n
go
es d
oub
le as th
at o
f
step
inp
u
t
v
a
l
u
e. The
m
a
i
n
o
b
j
ectiv
e in
activ
e d
v
/
d
t
filter is to
in
crease th
e rise
ti
m
e
an
d
fall ti
m
e
o
f
in
v
e
rter
o
u
t
pu
t vo
ltag
e
and
h
e
n
c
e
t
h
e rat
e
of ch
ange i
n
out
pu
t
vol
t
a
ge i
s
reduce
d
d
u
r
i
n
g
vol
t
a
ge t
r
an
s
i
t
i
ons by
effe
ct
i
v
el
y
chargi
ng a
n
d
d
i
sch
a
rg
i
n
g the filter cap
acito
r. Th
e ch
arg
i
n
g
and d
i
sc
h
a
rg
i
n
g of cap
a
cito
r is ach
i
ev
ed
b
y
m
o
d
i
fying
the
PW
M p
u
l
ses. Th
e
step
respon
se o
f
un-d
a
m
p
ed
sing
le
p
h
a
se LC filter ci
rcu
it is g
i
v
e
n b
y
equ
a
tio
n (10
)
,
(
1
0)
In
verte
r
v
o
ltag
e
pulses a
r
e fe
d to the
LC fi
lter fo
r a pe
riod
of tim
e (
)
d
u
r
i
ng
wh
ich
th
e ou
tput
v
o
ltag
e
o
f
th
e
LC filter rises to
h
a
lf th
e d
c
- lin
k
vo
ltag
e
d
u
e
to
ch
arg
i
ng
o
f
cap
acito
r. Wh
en
th
e LC filter
out
put voltage reaches
half
of
dc-link
voltage, stop fee
d
ing voltage to
t
h
e
LC filter. Ke
ep the switches
off
for
a p
e
r
i
od
of
time
) du
ri
n
g
whi
c
h
ca
paci
t
o
r di
s
c
har
g
es
a
n
d di
scha
rg
ing
tim
e
p
e
ri
o
d
is sam
e
as ch
arg
i
ng
time
(
) .
Du
ring this d
i
scharg
ing ti
m
e
in
terv
al
th
e cap
acitor vo
ltag
e
do
ub
l
e
s b
ecau
s
e of o
s
cillatio
n
s
du
e t
o
reso
na
nce an
d
at
t
h
e end o
f
d
i
schar
g
i
n
g t
i
m
e
peri
o
d
t
u
rn
o
n
t
h
e swi
t
c
he
s feedi
ng i
n
ve
rt
er o
u
t
p
ut
vol
t
a
g
e
s t
o
main
tain
th
e in
v
e
rter
o
u
t
p
u
t
v
o
ltag
e
level to
d
c
lin
k
vo
ltag
e
(
). Now th
e to
tal rise time o
f
th
e ou
tp
u
t
v
o
ltag
e
pu
lse i
s
in
creased
to
2
an
d
no
w
no
tran
sien
ts will o
ccur as t
h
e LC circu
it cap
acito
r vo
ltag
e
is
sam
e
as in
v
e
rter ou
t
p
u
t
v
o
ltag
e
. Th
e m
o
to
r termin
al v
o
ltag
e
peak
will rem
a
i
n
at d
c
lin
k
vo
ltag
e
lev
e
l an
d
no
v
o
ltag
e
reflectio
n ph
en
o
m
en
a
o
ccur and
h
e
n
c
e mitig
at
e th
e v
o
ltag
e
dou
b
l
i
n
g effect at m
o
to
r term
in
al.
Th
e cap
acito
r
ch
arg
i
ng
cu
rren
t flowing
thro
ugh
th
e i
n
ducto
r
rises th
e
in
du
ctor curren
t
wh
ich
i
s
carry
i
n
g t
h
e l
o
ad cu
rre
nt
du
ri
ng
pe
ri
o
d
an
d
du
ri
n
g
i
n
t
e
rva
l
i
nduct
o
r c
u
rr
ent
dec
r
eases
d
u
e t
o
di
scha
r
g
i
n
g
capaci
t
o
r c
u
r
r
e
n
t
.
If t
h
e c
u
r
r
e
n
t
fl
owi
n
g t
h
r
o
ug
h i
n
duct
o
r d
u
ri
ng c
h
ar
gi
n
g
and di
sc
har
g
i
ng i
s
fai
l
i
ng t
o
bri
n
g
b
ack th
e i
n
du
cto
r
cu
rren
t t
o
orig
in
al l
o
ad
curren
t
lev
e
l,
t
h
en
o
u
t
p
u
t
v
o
ltage
o
s
cillatio
n
s
can
h
a
pp
en
.
To
av
o
i
d
th
is ov
ershoo
t
d
u
e
to o
s
cillatio
n
s
a curren
t
co
rrectio
n
p
u
l
se is requ
ired
al
o
n
g
with ch
argin
g
and
d
i
sch
a
rg
i
n
g
t
i
m
i
ng se
q
u
enc
e
o
f
P
W
M
pul
s
e
s. T
h
e s
w
i
t
c
hi
n
g
in
stan
ts are
calcu
lated
as
fo
llo
ws.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-87
08
I
J
ECE
Vo
l. 6
,
N
o
. 4
,
Au
gu
st 2
016
:
14
56
–
1
469
1
460
Th
e pu
lse
length
is th
e tim
e
p
e
ri
o
d
du
ri
n
g
wh
ich
th
e filter cap
acito
r vo
l
t
ag
e will reach h
a
lf of
th
e d
c
link
v
o
l
t
a
g
e
.
Th
e inv
e
rt
er switch
e
s are ON
d
u
ring
t
h
is p
e
riod
and
cap
acito
r will get ch
arg
e
d
t
o
h
a
l
f
o
f
th
e
d
c
lin
k v
o
l
t
a
g
e
. Hen
ce filter o
u
t
p
u
t
vo
ltag
e
is g
i
v
e
n
b
y
eq
u
a
tion
(1
1),
(
1
1)
The ca
pacitor
charging tim
e interval
i
s
o
b
t
a
i
n
ed
f
r
om
equat
i
on
(
1
2
)
,
(12)
Th
e cap
acito
r
will d
i
sch
a
rg
e
for a period
o
f
ti
m
e
(
) during whic
h
the output
voltage
will reach
ful
l
dc l
i
n
k
vol
t
a
ge
.
Th
e
filter d
i
sch
a
rg
ing
tim
e i
s
sam
e
as th
e ch
arg
i
ng
tim
e
(
=
)and
d
u
ri
ng
in
terv
el i
n
v
e
rter
voltage
pulses are off.
(
1
3)
Now t
h
e
rise time of t
h
e
out
put voltage is
increased
and t
h
e rise tim
e is c
a
lculated
using equation (14).
(1
4)
3.
3.
Mo
difica
tion
of
PW
M se
qu
ence for
acti
ve contr
o
l
To
m
i
t
i
g
a
te th
e vo
ltag
e
doub
lin
g eff
ect in in
du
ction
m
o
to
r
d
r
i
v
e th
e
rise ti
m
e
o
f
inv
e
r
t
er ou
tpu
t
v
o
ltag
e
pu
lses can
b
e
in
creased
b
y
ch
arg
i
ng an
d
d
i
sch
a
rg
i
n
g
o
f
filter capacito
r b
y
th
e
m
o
d
i
fied
PWM p
u
l
ses.
In a t
w
o
l
e
vel
t
h
ree
pha
se i
n
v
e
rt
er t
h
e
u
ppe
r
swi
t
c
hes
of
t
h
e i
nve
rt
er l
e
g
m
odul
at
es t
h
e
ri
si
ng
v
o
l
t
a
ge
sl
ope
of
the corres
p
onding
phase a
nd l
o
we
r s
w
itches
m
odulates the
falling volta
ge slope
.
In
ac
tive
dv/dt filtering, edge
m
odulation ha
s
to be done for
the volta
ge st
ep in
addition t
o
norm
al phase
voltage m
odul
ation at the
swi
t
ching
freq
u
e
n
c
y.
If lo
ad curren
t
and
in
itial filter cu
rren
t are co
nsid
ered
as zero
th
en
PW
M m
o
d
i
ficatio
n can
b
e
d
o
n
e
by
pr
o
v
i
d
i
ng
m
odi
fi
ed del
a
y
pul
ses
based
on e
q
uat
i
o
n
s
(1
2) a
n
d (
1
3
)
.
The ca
paci
t
o
r
char
ges
or
di
schar
g
e
s
depe
nding
on t
h
e slope
direct
ions, whe
n
the
filter voltage
reache
d
half t
h
e
total voltage
transition, the
powe
r
switches are turne
d
off and the induct
or
cu
rr
en
t go
es th
ro
ugh
th
e freewh
eeling
d
i
o
d
es o
f
op
po
site switch
e
s.
Th
e ab
so
lu
te cu
rren
t
d
ecrease at th
e sam
e
rate as it
was in
creased
an
d
o
u
t
p
u
t
vo
ltag
e
o
f
filter
con
tin
u
e
s
to
i
n
crease o
r
dec
r
ease de
pen
d
i
n
g o
n
t
h
e di
rect
i
on o
f
v
o
l
t
a
ge.
Then t
h
e sam
e
po
wer swi
t
c
h i
s
swi
t
c
hed o
n
w
h
e
n
th
e cu
rren
t h
a
s retu
rn
ed
to
the sa
m
e
v
a
lu
e as it was b
e
fo
re th
e tran
sien
t an
d
t
h
e vo
ltag
e
h
a
s reach
e
d
dc lin
k
val
u
e.
Th
e abo
v
e
m
e
t
h
od
is
go
od
only if th
e lo
ad
cu
rren
t an
d
in
iti
al filter curren
t
is zero
.
B
u
t it
is o
b
serv
ed
th
at th
is m
e
th
o
d
h
a
s issu
es
wh
en
t
h
e lo
ad curren
t
exists
. T
h
e inc
r
ease
or decrease
in loa
d
c
u
rre
nt cause
s
o
s
cillatio
n
s
in
o
u
t
p
u
t
v
o
ltag
e
in
p
r
op
ortion
to
th
e ratio
o
f
l
o
ad
cu
rren
t to
filter cu
rren
t.
Hen
ce t
h
e lo
ad cu
rren
t
creates an error in active
dv/dt contro
l
e
xpl
ai
ned
ab
o
v
e. C
o
nsi
d
e
r
i
n
g si
n
g
l
e
l
e
g o
f
i
nve
rt
er as s
h
ow
n i
n
Fi
gu
re
2, duri
ng active dv/dt control whe
n
the voltage of capacitor r
eaches hal
f
of the dc link
voltage, powe
r switche
s
will g
o
o
f
f and th
e filter cu
rren
t
will freewh
eel th
rou
g
h
th
e an
ti-p
a
rallel
d
i
od
e of th
e
op
po
site switch
an
d
t
h
e
cur
r
ent
begi
ns
t
o
decre
a
se as
sho
w
n i
n
Fi
gu
re 3
(
a)
-(
d)
if t
h
e lo
ad
current is zero
.
Bu
t i
f
lo
ad
curren
t
ex
ists,
t
h
en
de
pen
d
i
n
g o
n
t
h
e i
n
st
a
n
t
a
neo
u
s
val
u
es
and
di
rect
i
o
n
of loa
d
c
u
rrent,
a curre
n
t
co
rre
ct
i
on pul
se
i
s
r
e
qui
re
d
to
bring
t
h
e l
o
ad
cu
rren
t to
it
s orig
inal v
a
l
u
e. Th
is
iss
u
e
due t
o
loa
d
c
u
rrent ca
n
ove
rc
o
m
e by
i
n
c
o
r
p
o
r
at
i
n
g
a
cur
r
ent
c
o
rrect
i
o
n
p
u
l
s
e al
on
g
wi
t
h
t
h
e
P
W
M
pul
se
m
odi
fi
cat
i
on e
xpl
ai
ned
abo
v
e a
s
s
h
o
w
n i
n
Fi
g
u
r
e
3.
Fi
gu
re
2.
Si
n
g
l
e
l
e
g
of
t
h
e i
n
v
e
rt
er
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
ECE
I
S
SN
:
208
8-8
7
0
8
Active LC Clamp d
v
/
d
t Filter fo
r Vo
ltag
e
Reflectio
n
du
e t
o
Lon
g
Cab
l
e in
Indu
ctio
n .... (
M
in
i R)
1
461
Ca
se
1a
: Rising
vo
lta
g
e
slop
e an
d loa
d
curren
t po
sitive
If th
e lo
ad
cu
rren
t is po
sitiv
e, th
e rising
vo
l
t
ag
e
slop
e is
no
t affected and th
e
filter
o
p
e
rates no
rm
all
y
du
ri
n
g
f
r
eew
h
eel
i
ng m
ode. Onl
y
m
odi
fi
ed
P
W
M
p
u
l
s
es
are require
d
and
no c
u
rre
n
t correcti
on
pulses are
r
e
qu
ir
ed
. The in
du
ctor
cur
r
e
nt is as
sh
o
w
n
in
Figu
r
e
3(
h) an
d
th
e PWM pu
lses to
switch A an
d
A' is sh
o
w
n
in
Fi
gu
re 3(a
)
&
(
b
)
.
Ca
se1b: Fa
llin
g
vo
lta
g
e
slop
e an
d loa
d
curren
t po
sitive
If the l
o
ad c
u
rrent is positive,
the falling
voltage sl
ope gets affe
cted because during
free
w
heeli
ng
m
o
d
e
th
e curren
t will no
t retu
rn
to
t
h
e same v
a
lu
e as i
n
th
e
b
e
g
i
n
n
i
n
g
o
f
edg
e
m
o
dulatio
n
Figure 3(h).
To
b
r
i
n
g
th
e i
n
ductan
ce curren
t
b
ack
t
o
in
itial
p
o
s
itiv
e
v
a
lu
e
th
e switch
p
a
rallel to
th
e co
nd
u
c
ting
d
i
od
e
n
eeds to
b
e
turn
ed
o
n
. i.e. upp
er switch
(A)
h
a
s to
be tu
rn
ed
on
. Th
e appr
op
r
i
ate co
rr
ectio
n
pu
lses to
tu
rn
o
n
u
pper
swi
t
c
h
(A
) al
o
n
g
wi
t
h
m
odi
fi
ed P
W
M
p
u
l
s
e seq
u
e
n
ce i
s
s
h
ow
n i
n
Fi
gu
re
3(i
)
.
Ca
se
2
a
: Fa
llin
g vo
ltag
e
slope an
d loa
d
curren
t
n
e
ga
tive
If t
h
e l
o
ad curren
t is
n
e
g
a
ti
v
e
, th
e
fallin
g vo
l
t
ag
e slop
e is no
t affected and th
e
filter op
erates no
rm
ally
du
ri
n
g
f
r
eew
h
eel
i
ng m
ode. Onl
y
m
odi
fi
ed
P
W
M
p
u
l
s
es
are require
d
and
no c
u
rre
n
t correcti
on
pulses are
r
e
qu
ir
ed
. Th
e i
n
du
ctor
cu
rr
ent is as sh
own
i
n
Figur
e 3(
e)
an
d
t
h
e PW
M pu
lses to
sw
itch A
an
d
A
'
is sho
w
n
in
Fi
gu
re 3(a
)
&
(
b
)
.
Ca
se
2
b
:
Risi
ng
vo
lta
g
e
slop
e an
d loa
d
curren
t n
e
ga
tive
If th
e lo
ad
cu
rren
t is n
e
g
a
tive, th
e risin
g
vo
ltag
e
slope gets affected be
cause duri
ng freewheeli
ng
m
ode the current will not re
turn to t
h
e sa
m
e
negative
value as in
the
begi
nni
ng of e
dge
m
odulation Fi
gure
3
(
e). To
bring
th
e in
du
ctan
ce
cu
rren
t
b
ack
to in
itial v
a
lu
e t
h
e switch
p
a
ral
l
el to
th
e co
n
d
u
c
tin
g
d
i
od
e need
s
t
o
b
e
tu
rn
ed
o
n
. i.e. lo
wer switch
(A') h
a
s to
be tu
rn
ed
on. T
h
e appropriate correctio
n
pu
l
s
es to
tu
rn
o
n
lo
wer
swi
t
c
h
(A'
)
al
o
n
g
wi
t
h
m
odi
fi
ed P
W
M
p
u
l
s
e seq
u
e
n
ce i
s
s
h
ow
n i
n
Fi
gu
re
3(
g)
.
Th
e len
g
t
h
o
f
t
h
e cu
rren
t correctio
n
pu
lse
wh
en lo
ad
curren
t
is
b
e
tween
zero and filter
p
eak cu
rren
t
can be obt
ai
ne
d fr
om
equat
i
o
n (1
5)
(
1
5)
whe
r
e
is th
e in
stan
tan
e
o
u
s
v
a
l
u
e of lo
ad
curren
t. Bu
t wh
en
lo
ad
cu
rren
t is g
r
eater t
h
an
filter p
eak
current th
e
cu
rren
t correcti
o
n pu
lse
wid
t
h
will
b
e
h
a
lf of ch
arg
i
ng
p
e
ri
od
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-87
08
I
J
ECE
Vo
l. 6
,
N
o
. 4
,
Au
gu
st 2
016
:
14
56
–
1
469
1
462
Fi
gu
re
3.
Act
i
v
e
dv/
dt
o
p
e
r
at
i
on
wi
t
h
m
odi
f
i
ed P
W
M
pul
s
e
s an
d c
u
r
r
e
n
t
cor
r
ect
i
o
n
p
u
l
s
es f
o
r
o
n
e l
e
g
of
i
nve
rt
er
Th
e algorith
m for g
e
n
e
ratio
n o
f
activ
e
dv
/dt co
n
t
ro
l with
cu
rren
t co
rrect
io
n
p
u
l
ses
fo
r
o
n
e
leg
o
f
i
nve
rt
er i
s
gi
ve
n i
n
Fi
g
u
r
e
4.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
ECE
I
S
SN
:
208
8-8
7
0
8
Active LC Clamp d
v
/
d
t Filter fo
r Vo
ltag
e
Reflectio
n
du
e t
o
Lon
g
Cab
l
e in
Indu
ctio
n .... (
M
in
i R)
1
463
Fi
gu
re
4.
Al
go
ri
t
h
m
for i
m
pl
em
ent
a
t
i
on
of c
u
r
r
ent
c
o
rrect
i
o
n
p
u
l
s
e al
on
g
wi
t
h
m
odi
fi
ed
P
W
M
pul
se
sequ
en
ce fo
r on
e leg of
i
n
v
e
r
t
er
St
ep 1:
Norm
a
l
PW
M pulses
for upper s
w
i
t
ch (A) a
nd l
o
we
r
s
w
itch (A’) for
each
single
leg
of inve
rter is
g
e
n
e
rated b
y
co
m
p
arin
g sinu
so
id
al si
g
n
a
l
wi
th
triangu
lar
wav
e
fo
rm
.
St
ep 2
:
Th
ese no
rm
al PW
M
pu
lses are mo
d
i
fied
b
a
sed
o
n
filter cap
a
cito
r ch
arg
i
ng
an
d d
i
sch
a
rg
i
n
g
tim
e
sequence
(
).
St
ep 3:
If lo
ad
cu
rren
t is
po
sitiv
e fo
r
rising
ed
g
e
th
en
m
o
d
i
fied
PW
M
pu
lses
are o
n
l
y requ
ired
and
no
need
o
f
cu
rren
t co
rrectio
n
p
u
l
se. B
u
t if th
e lo
ad
curren
t
is n
e
g
a
ti
v
e
fo
r
risin
g
ed
g
e
t
h
en
cu
rren
t co
rrection
pu
lse is
requ
ired
alon
g with
PW
M m
o
d
i
fied
p
u
l
ses
to
lo
wer switch
(A’) to
b
r
i
n
g th
e lo
ad
curren
t
to
its o
r
i
g
inal v
a
lue
i.e. to
bring
ind
u
c
t
o
r curren
t
to
lo
ad
curren
t
lev
e
l.
Si
m
i
l
a
rly for
fallin
g vo
ltag
e
sl
o
p
e
if th
e lo
ad
curren
t
is
negat
i
v
e
,
o
n
l
y
m
odi
fi
ed P
W
M
p
u
l
s
es are
r
e
qui
red
an
d
n
o
correction
pu
lse is requ
ired
.
And
i
f
th
e lo
ad
cu
rrent
is p
o
s
itiv
e fo
r
fallin
g
edg
e
then
correction
pu
lse alo
n
g
wit
h
m
o
d
i
fied
PWM pu
lse is req
u
i
red
to
u
pper switch
(A) to bring
i
n
d
u
c
t
o
r curren
t
to
lo
ad
cu
rren
t
lev
e
l.
St
ep 4:
Th
e wi
d
t
h
o
f
curren
t
co
rrectio
n
pu
lse
d
e
p
e
nd
s o
n
ratio
o
f
l
o
ad
curren
t
to
filter
peak
curren
t.
If
lo
ad
current (
I
L
) is
less th
an
filter p
eak curren
t
v
a
lu
e(
I
fpk
)
,
wi
d
t
h o
f
t
h
e c
o
r
r
e
c
t
i
on
pul
se
(
t
add
) is calculated
as pe
r
eq
u
a
tion
15
.
And
i
f
lo
ad
cu
rren
t is
great
er
th
an
filter p
eak
curren
t
, wid
t
h of co
rrectio
n
p
u
l
se is
h
a
lf
o
f
charging peri
od.
4.
RESULT A
N
D
AN
ALY
S
IS
Si
m
u
latio
n
is
carried ou
t in
MATLAB
-
Si
m
u
l
i
n
k
so
ft
ware to
an
alyze th
e
v
o
ltag
e
reflectio
n
d
u
e
to
lo
ng
cab
le in
a 4
k
W indu
ctio
n
m
o
to
r
d
r
i
v
e. Th
e cab
l
e is
m
o
d
e
led
b
a
sed
on
d
i
stribu
ted
tran
sm
issio
n
line
m
o
d
e
l an
d th
e cab
le ch
aracteristics req
u
i
red fo
r m
o
d
e
lin
g
is
selected
from
Be
lden ca
bl
e data
sheet
of cable
part num
ber 29502
m
u
lti
conduct
o
r 1000V UL
fle
x
ible
m
o
tor supply cable. T
h
e m
o
tor param
e
ters and cable
p
a
ram
e
ters are g
i
v
e
n
in
Tab
l
e I an
d
II. Simu
latio
n
is carri
ed
ou
t in
in
ductio
n
m
o
to
r d
r
iv
e with
cab
le
m
o
d
e
l
an
d ob
serv
ed
t
h
e
h
i
gh
v
o
ltage at m
o
to
r termin
al sid
e
du
e to
v
o
ltag
e
reflectio
n
ph
e
nomena. In t
h
e
previ
ous
p
a
rt of th
is work
a p
a
ssiv
e
LC d
i
o
d
e
clam
p
e
d
filter is d
e
sig
n
e
d
and
an
alyzed
its effectiv
en
ess b
y
simu
latio
n
fo
r vari
ou
s cabl
e
l
e
ngt
h
s
ran
g
i
n
g fr
om
100
m
t
o
100
0m
and re
p
o
rt
e
d
[1
0]
. In t
h
i
s
pa
p
e
r act
i
v
e LC
cl
am
pe
d
filter is in
v
e
sti
g
ated
t
o
m
i
t
i
g
a
te th
e ov
er
vo
ltag
e
at m
o
to
r term
in
al an
d
to
red
u
c
e th
e
filter size and
h
e
n
c
e th
e
cost a
n
d losses
in the
system
.
Th
e m
a
in
ad
v
a
n
t
ag
e
o
f
t
h
is tech
n
i
q
u
e
is th
at
th
e h
i
g
h
vo
ltage at
m
o
to
r termin
al can
b
e
li
mited
to
th
e
d
e
sired
safe li
mit with
activ
e d
v
/
d
t
filter wh
ere th
e size
o
f
filter can
be redu
ced
to
a g
r
eat ex
ten
t
by activ
e
dv/
dt control of t
h
e filter without a
n
y ext
r
a de
vices or
hardware
requirem
e
nt. The rise tim
e
of the input
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-87
08
I
J
ECE
Vo
l. 6
,
N
o
. 4
,
Au
gu
st 2
016
:
14
56
–
1
469
1
464
v
o
ltag
e
to
t
h
e
m
o
to
r is in
creased
b
y
th
e
com
b
in
ed
effect
o
f
sm
al
l LC filter and
th
e mo
d
i
fied
PW
M
p
u
l
ses
with
calcu
lated switch
i
n
g
ti
mes
and c
u
rre
n
t
correction puls
es.
Detailed
inv
e
st
ig
atio
n
is carri
ed
o
u
t
to m
i
tig
ate th
e
vo
ltag
e
reflection
effect at
m
o
to
r termin
al with
LC
cl
am
ped fi
l
t
e
r desi
g
n
ed
f
o
r
vari
ous ca
b
l
e l
e
ngt
hs
wi
t
h
i
t
s
act
i
v
e con
t
rol
by
m
odi
fi
ed P
W
M
p
u
l
s
es. To
stan
d
a
rd
ize th
e filter size, a co
mm
o
n
filter su
itab
l
e fo
r cab
l
e len
g
t
h
up
to
1
000
m
an
d
its activ
e co
n
t
ro
l
b
y
th
e
m
odi
fi
ed P
W
M
pul
ses
dep
e
ndi
ng
o
n
t
h
e
cor
r
esp
o
ndi
n
g
l
e
n
g
t
h
i
s
de
si
gne
d an
d si
m
u
l
a
t
e
d t
o
val
i
dat
e
i
t
s
per
f
o
r
m
a
nce.
A co
m
p
arativ
e an
alysis o
f
p
e
rfo
r
m
a
n
ce with
ou
t filte
r, wit
h
p
a
ssi
v
e
LC d
i
od
e clam
p
e
d
d
v
/
d
t
filter,
active LC diode clam
ped dv/
dt filte
r for
various ca
ble lengths rangin
g from
100m
to 1000m
and a com
m
o
n
d
i
od
e clam
p
e
d LC
d
v
/
d
t
filter
with
its active con
t
ro
l
d
e
p
e
n
d
i
n
g
o
n
leng
th
o
f
cab
l
e is
g
i
v
e
n in Tab
l
e III.
The
pl
ot
s s
h
owi
n
g
t
h
e a
b
o
v
e a
n
al
y
s
i
s
fo
r
1
00m
and
1
0
00m
cabl
e
are s
h
ow
n i
n
Fi
gu
re
5 a
n
d Fi
gu
re
6.
Table
1. M
o
tor Speci
fications
Rated Speed
Rated T
o
r
que
Nu
m
b
er
of poles
Voltage
1430 r
p
m
26.
7 Nm
4
400 V
Table 2.
Ca
ble Specifications
Fig
u
re
5
a
. Simu
latio
n
resu
lt of inv
e
rter
o
u
t
pu
t vo
ltag
e
and
m
o
to
r term
in
al
vo
ltag
e
for
1
0
0
m
cab
le len
g
t
h
with
ou
t filter
Fig
u
re 5b
. Simu
latio
n
resu
lt
of
i
n
v
e
rter ou
tpu
t
vo
ltag
e
and
m
o
to
r
term
in
al
vo
ltag
e
for 1
0
0
m
cab
le
len
g
t
h
with
p
a
ssiv
e
LC clam
p
e
d
d
v
/
d
t
filter
Characteristic
i
m
p
e
dance
80
Ω
I
nductance 0.
6988
53
(
μ
H/
m
)
Capacitance 137.
80
2
(
p
F/m
)
Resistance 8.
2681
2
Ω
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
ECE
I
S
SN
:
208
8-8
7
0
8
Active LC Clamp d
v
/
d
t Filter fo
r Vo
ltag
e
Reflectio
n
du
e t
o
Lon
g
Cab
l
e in
Indu
ctio
n .... (
M
in
i R)
1
465
Fig
u
re
5
c
. Simu
latio
n
resu
lt of inv
e
rter
o
u
t
pu
t vo
ltag
e
and
m
o
to
r term
in
al
vo
ltag
e
fo
r
100
m
cab
le len
g
t
h
with
activ
e LC clamp
e
d dv
/d
t
filter
Fig
u
re
5
(
a),(b),(c) sh
ows t
h
e lin
e to
li
n
e
vo
ltag
e
s
of
i
n
v
e
rt
er
out
put
v
o
l
t
a
ge a
n
d
m
o
t
o
r t
e
rm
i
n
al
v
o
ltag
e
for a cab
l
e leng
th of
1
0
0
m
w
ith
ou
t filter, with
p
a
ssiv
e d
v
/
d
t
filter
and
with
active
dv
/d
t filter. Th
e p
e
ak
val
u
e o
f
i
nve
rt
er out
put
v
o
l
t
a
ge i
s
56
5V
w
h
ere as t
h
e
mo
tor termin
al
v
o
ltag
e
is in
creased
to
74
2V d
u
e
to
v
o
ltag
e
reflectio
n du
e t
o
100
m
cab
le. A
p
a
ssiv
e
filter
with
i
n
du
ctor
an
d cap
acito
r
v
a
lu
es of
1
.
8m
H an
d
7
.
7
43n
F redu
ced
th
is ov
erv
o
l
tag
e
at
m
o
to
r term
in
al fro
m 7
4
2
V to
568
V. Bu
t in
activ
e LC cla
m
p
e
d
d
v
/
d
t
filter
wi
t
h
i
n
d
u
ct
or
and ca
paci
t
o
r
val
u
es
of
45
0µ
H an
d 6
8
.
9
5
n
F
,
t
h
e o
v
er
vol
t
a
ge at
m
o
t
o
r t
e
r
m
i
n
al
i
s
reduc
ed fr
om
7
42V to
5
75V. By u
s
i
n
g activ
e LC
dv
/d
t
filter th
e
filter in
d
u
c
t
o
r size is
redu
ced
to 1
/
4
t
h
as th
at
requ
ired
for
p
a
ssiv
e
filter an
d
it h
e
lp
s to
red
u
ce th
e
o
v
e
r v
o
ltag
e
in
li
mit an
d
o
v
e
r vo
ltag
e
ap
p
e
aring acro
ss m
o
to
r term
in
al
is on
ly 1
.
8
%
with
resp
ect to rated
v
a
l
u
e.
Fig
u
re
6
a
. Si
m
u
la
tio
n
resu
lt
of i
n
v
e
rter
outp
u
t
v
o
ltage and
m
o
to
r term
in
al v
o
ltage for
10
00
m
cab
le leng
th
with
ou
t filter
Fig
u
re 6b
. Simu
latio
n
resu
lt
of
inv
e
rter o
u
t
pu
t
vo
ltag
e
and
m
o
to
r
term
in
al
vo
ltag
e
for 1
0
0
0
m
cab
le
length
with
p
a
ssiv
e
LC clam
p
e
d
d
v
/
d
t
filter
Evaluation Warning : The document was created with Spire.PDF for Python.