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

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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

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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

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VRM for Microprocessors

LPKEE-ITB 29

Experimental Result

LPKEE-ITB 30

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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

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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

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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

23

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

4/5/2010

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Future Trends

LPKEE-ITB 51

Future Trends

LPKEE-ITB 52

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End

LPKEE-ITB 53