4/5/2010
1
Konverter DC-DC
Pekik Argo Dahono
1LPKEE-ITB
Penerapan
• Catu daya switching
• Pengendalian motor dc
• Regulator tegangan dc
2LPKEE-ITB
4/5/2010
2
Regulator Tegangan
iV
oV
oI
oR
1R
2R
iV
oV
oI
oR
vR
3LPKEE-ITB
Regulator tegangan
iV oV
oIiI
Load
ONT
sT
0
iV
0
0
oV
oI
iI
4LPKEE-ITB
4/5/2010
3
DC Power Supplies
Hz 50 V/ 220 oV
oI
Load oV
oI
•
•Hz 50 V/ 220
Linear Regulator
Switching Regulator5
LPKEE-ITB
Jenis Konverter DC-DC
Direct converters:• Step-down (Buck)
• Step-up (Boost)
• Up-Down (Buck-Boost)
• Cuk
Indirect converters:• Flyback
• Forward
• Center-tap
• Half-bridge
• Full bridge6LPKEE-ITB
4/5/2010
4
Klasifikasi Konverter DC-DC
1) Berdasarkan jumlah fasa
• Satu-fasa
• Multifasa
2) Jumlah kuadran
• Satu kuadran
• Dua kuadran
• Empat kuadran
7LPKEE-ITB
Step-Down (Buck) Converter
8LPKEE-ITB
4/5/2010
5
Step-Down Converter
(Continuous Conduction Mode)
oL
L
D
sON
oL
Ld
dD
ON
oL
LD
vdt
diLRi
v
TtT
vdt
diLRiE
Ev
Tt
vdt
diLRiv
++=
=
<≤
++=
=
<≤
++=
0
0
:
:0
ON state
OFF State
9LPKEE-ITB
Step-Down Converter
(Continuous Conduction Mode)
( )∫∫ −==
+=+=
=+=+=
==+
=
dtvvL
dtvL
i
iR
dt
idLiRvViRv
Vvvvviii
dEET
TE
TT
Tv
DDDL
o
LLDoLD
ooDDDLLL
dds
ONd
OFFON
OND
1~1~
:maka kecil dianggap~
nilai Jika
~~~
Thus,
~ ~
:Riak Analisis
:rata-rataTegangan
Dv
0
dE
ds
OND E
T
Tv =
ONT
sT
Li
Lvod vE −
ov−
di
10LPKEE-ITB
( )
factor.duty adalah /
switching frekuensiadalah /1
1
~,
sON
ss
s
ds
dd
OFFD
ONDd
ppL
TTd
Tf
ddLf
EdT
L
dEE
TL
vT
L
vEi
=
=
−=−
=
=−
=
4/5/2010
6
Critically Conduction Mode
( )
2
1
2
~dd
Lf
Eii
s
dLppL
−
==
Dv
0
dE
ds
OND E
T
Tv =
ONT
sT
Li
Lv
od vE −
ov−
Lppi~
0
11LPKEE-ITB
Discontinuous Conduction Mode
12LPKEE-ITB
4/5/2010
7
Output voltage characteristic
LPKEE-ITB 13
Step-Up (Boost) Converter
14LPKEE-ITB
Vo > Ed
4/5/2010
8
Step-Up Converter
(Continuous Conduction Mode)
( )
d
EV
VdVvE
VT
Tv
v
VEvvTtT
EvVvTt
VvvE
do
ooDd
o
s
OND
L
odLDsON
dLoDON
oDLd
−=
−=+−=
=
=
−==⇒<≤
==⇒<≤
+−=
1
1
jadi,
,0induktor di tegangan rata-rata Nilai
0
0
:umumPersamaan
15LPKEE-ITB
ON state
OFF state
Step-Up Converter
(Continuous Conduction Mode)
( )
dLf
E
TL
ET
L
VEi
dtVEL
i
VT
Tv
VvTtT
vTt
vEdt
diL
s
d
ONd
OFFod
ppL
odL
o
s
OFFS
oSsON
SON
SdL
)(~
1~
00
:arusriak Persamaan
,
=
=−−
=
−=
=
=⇒<≤
=⇒<≤
−=
∫
16LPKEE-ITB
4/5/2010
9
Critically Conduction Mode
dLf
Ecriti
s
dL
2, =
17LPKEE-ITB
Discontinuous Conduction Mode
18LPKEE-ITB
ON state
OFF state
OFF state
4/5/2010
10
Output characteristic
LPKEE-ITB 19
Parasitic effect
LPKEE-ITB 20
4/5/2010
11
Buck-Boost Converter
dE
Sdi D
L
Di
C
oi
ovciDvLiSv
Lv
21LPKEE-ITB
Buck-Boost Converter
d
OFF
ONo
OFFoONd
L
oL
sON
Ld
ON
ET
Tv
TvTE
v
vv
TtT
vE
Tt
=
=
=
−=
<≤
=
<≤
Thus,
then0, Bevause
0
dE
Sdi D
L
Di
C
oi
ovciDvLiSv
dE
Sdi D
L
Di
C
oi
ovciDvLiSv
ONTt <≤0
sON TtT <≤
Lv
Lv
22LPKEE-ITB
4/5/2010
12
Buck-Boost Converter
Continuous Conduction Mode
d
dEv do
−=
1
dLf
Ei
s
dLpp =
23LPKEE-ITB
Cuk Converter
24LPKEE-ITB
4/5/2010
13
Cuk Converter
dOFF
ONo
OFFoOFFdcONd
CdLsON
dLON
odC
LL
LoCLd
ET
Tv
TvTEvTE
vEvTtT
EvTt
vEv
vv
vvvvE
=
=−=
−=⇒<≤
=⇒<≤
+=
==
−−+=
)(
Thus,
0
0
:teganganPersamaan
1
1
21
21
ONTt <≤0
sON TtT <≤
dE S
di
D
1L C
2LCv
oiov
dC
2Lv
1Lv
Sv
dE S
di
D
1L C
2LCv
oiov
dC
2Lv
1Lv
Sv
25LPKEE-ITB
Multiphase Choppers
dE C
oi
ovci
1S
2S
1D 2D
1i
2i
dE C
oi
ovci
1S
2S
3S
1i
2i
3i
26LPKEE-ITB
4/5/2010
14
Two-Phase Chopper
1Dv
1i
2Dv
2i
oi
27LPKEE-ITB
Multiphase Chopper
• The effective switching frequency is the number of phase times the carrier frequency.
• At several values of duty cycle, the ripple is zero.
• The topology is useful for low-voltage high-current applications.
• The flywheel diodes are usually implemented by using synchronous rectifiers.
28LPKEE-ITB
4/5/2010
15
VRM for Microprocessors
LPKEE-ITB 29
Experimental Result
LPKEE-ITB 30
4/5/2010
16
Multi-quadrant Chopper
dE
1S
2S
1D
2D
oi
ov
dE
1S
2S
1D
2D
3S
4S
3D
4D
31LPKEE-ITB
Two-Quadrant Chopper
dE
1S
2S
1D
2D
oi
oeov
ovR L
oeoi
ov
oe
+ov
−ov
+oi
−oi
1/1 DS 2/2 DS
32LPKEE-ITB
4/5/2010
17
Four-Quadrant Chopper
2Dv
R Loe
4Dv
oi
*2Dv
*4Dv
2Dv
4Dv
ovoi
dE
1S
2S
1D
2D
3S
4S
3D
4D
oi
ov
33LPKEE-ITB
Indirect DC-DC Converters
• Flyback converter
• Forward converter
• Pushpull converter
• Half-Bridge converter
• Full-bridge converter
34LPKEE-ITB
4/5/2010
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The needs of galvanic isolation
• Safety and noise requirements dictate the
use of galvanic isolation.
• Galvanic isolation is implemented by using
a transformer.
• The frequency of operation must be very
high to reduce the size of transformer.
35LPKEE-ITB
Flyback converter
• Simple
• Minimum component count
• Higher stresses across switching devices
• Unipolar flux in the transformer
• Higher ripple
• Suitable for low-power applications (<150
W)
36LPKEE-ITB
4/5/2010
19
Flyback converter
D
•
•
Load1N 2N C ov
dE
S
•
•
Load1N 2N C ov
dE
S
ONTt <≤0
D
•
•
Load1N 2N C ov
dE
S
sON TtT <≤
37LPKEE-ITB
Flyback Converter
odS
oLm
sON
S
Lmd
ON
Lm
SLmd
vN
NEv
vN
Nv
TtT
v
vE
Tt
v
vvE
2
1
2
1
0
0
fo.primer tra sisitegangan
:umumPersamaan
+=
−=
<≤
=
=
<≤
+=
38LPKEE-ITB
OFF
ONdo
OFFoONd
T
TE
N
Nv
TvN
NTE
1
2
2
1
jadi
nol,dengan sama harus trafodi
tegangan rata-rata Nilai
=
=
4/5/2010
20
Forward Converter
• Simple
• Less ripple than flyback converter
• Less stresses across switching devices
• Unipolar flux
• Suitable for medium power (< 500 W)
39LPKEE-ITB
Forward Converter1D
• •
1N 2N
dE
S
LoadC ov2D
L
1D
•
2N LoadC ov2D
L
•
1N
dE
S
•
3D
40LPKEE-ITB
4/5/2010
21
Forward Converter1D
•
2N LoadC ov2D
L
•
1N
dE
S
•
ONTt <≤0
3D
1D
•
2N LoadC ov2D
L
•
1N
dE
S
•
3D
sON TtT <≤
41LPKEE-ITB
Forward Converter
s
ONdo
DsON
dsekDON
oDL
oLD
T
TE
N
Nv
vTtT
EN
NvvTt
vvv
vvv
1
2
2
1
22
2
2
Jadi,
0:
:0
:teganganPersamaan
=
=<≤
==<≤
−=
+=
42LPKEE-ITB
4/5/2010
22
Push-Pull and Half-Bridge Converters
3D
dE
C ov
4D
L
• •
• •
Load
1S
1D
2S
2D
dE
1S1D
2S 2D
3D
C ov
4D
L
Load
dE
43LPKEE-ITB
Push-Pull and Half-Bridge Converters
• Bipolar flux
• Moderate stress across switching devices
• Suitable for medium power (< 1 kW)
• Sensitive to signal unbalances
44LPKEE-ITB
4/5/2010
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Full-Bridge Converter
3D
C ov
4D
L
LoaddE
1S1D
2S 2D
3S 3D
4S 4D
u v
uvv S1 S2 S3 S4
dE ON OFF OFF ON
- dE OFF ON ON OFF
0 OFF ON OFF ON
0 ON OFF ON OFF
45LPKEE-ITB
Full-Bridge Converter
• Bipolar flux
• Minimum stresses across switching
devices
• Suitable for large power (< 10 kW)
• Can be operated under soft-switched
mode
46LPKEE-ITB
4/5/2010
24
Soft-Switching Mode
ui
4&1 SS
3&2 SS
uvv
ui
47LPKEE-ITB
Duality
inV
1S
2S
inI
outV outI
out
in
in
out
I
Id
V
V==
inI inV
1S
2SoutV
outI
out
in
in
out
I
I
dV
V==
1
48LPKEE-ITB
4/5/2010
25
Duality
inV
inI
1S
L
2S
outV
outI
inIoutI
C
1S 2S
49LPKEE-ITB
Future Trends
LPKEE-ITB 50
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Future Trends
LPKEE-ITB 51
Future Trends
LPKEE-ITB 52
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End
LPKEE-ITB 53