Rozdział IV Uklady zasilania i stabilizacji
Chapter IV Power supplies and stablizers

B.Piwakowski Analog electronics ,

Chapter IV Supply Systems

B.Piwakowski Analog electronics ,

Chapter IV Supply Systems

V

1

C2

E+De

I

o

220 V

rms

+
-

V

2

n1 : n2

C2

Stabilizator
Stabilizer
or DC/DC
Concverter

Uo+Du

Prostownik dwu polowkowy

Full wave rectifier

Zasilanie , typowe rozwiazania

Power supply, typical solutions

Transformator

transformer

Masa potencial referencyjny « 0 » V
« ground » Reference potential « 0 » V

Bezpiecznik

fuse

B.Piwakowski Analog electronics ,

Chapter IV Supply Systems

Transformator
Transformer

V

2

Sprawność Power efficiency

h

V

1

I

2

I

1

R

2

R1

=

=n

= h

≈

= =n

R1=

=

/

=R

2

Przekładnia rapport n1 : n2

n1 : n2 = n

Transformator « transformuje » oporność n

2

razy

Transformers « transforms » resistivity n

2

times

B.Piwakowski Analog electronics ,

Chapter IV Supply Systems

V

1

C2

I

L

220 V

rms

+
-

V

2

n1 : n2 = n

C2

Uo+Du

Prostownik dwu polowkowy

Full wave rectifier

Zasilanie , typowe rozwiazania

Power supply, typical solutions

Transformator

transformer

Bezpiecznik

fuse

-V

2

 

 

 

0

V

V

U

sin

V

sin

V

)

(

V

sin

V

)

(

V

1

2

0

1

2

2

1

1















L

m

m

m

m

m

I

if

n

t

n

t

t

t

t







t

Uo

Rectified DC ouput tension

Du

U≈(V

2m

)

V

1

C2

220 V

rms

+
-

V

2

n1 : n2

I

L

U+Du

Inne popularne rozwiazanie: Prostownik (mostek) Graetz’a
Another popular solution : Graetz rectifier (bridge)

B.Piwakowski Analog electronics ,

Chapter IV Supply Systems

Eo+De

i

L

Stabilizer

Uo+Du

E

U

=

,

∆ =

∆ +

∆

∆ =

∆ −

∆

I

L

=cons, =>Di

L

=0

Eo

U=const =>DU=0

i

L

K=

=

R

Perfect stabilizer

K=0, Rs=0

h=1

Zone of stabilization

i

L

L

L

L

P

P

I

E

P

I

U

P

L

o

o

0









Sprawnosc Efficiency

small

Low?

Eo

Stabilizator Stabilizer

B.Piwakowski Analog electronics ,

Chapter IV Supply Systems

E+De,

U+Du

Rozwiazania stabilizatorow Solutions for stabilizers

U

z

R

L

U

Rs

I

L

Rs

•

Simplest, easy to realise, cheap

•

But : high power dissipated on Rs

•

power efficency h=10%

•

Used only for small I

L

( <100 ma)

•

E≈Uz

•

K=0,2

•

Rs=Rd

V

CE

V

BE

R

U

z

U+Du

R

L

I

L

E+De,

•

Medium power efficency h 20-30%

•

P

dissipated

=V

ce

x I

L

=(U-E) x I

L

•

Needs radiator I

L

•

E≈Uz+Ud

•

K=0,01

•

Rs ≈ 1 small

E+De

I

L

DC/DC Converter
with stabilisation

U+Du

R

•

High power efficency 80-90%%

•

E≈U x d, 0< d, <1

•

K=0,01

•

Rs ≈ 1 small

•

Mostly used in recent solutions

B.Piwakowski Analog electronics , Chapter IV Supply Systems

DC/ DC Converter ,

∆ =

8

(1 − )

•

Output tension E may be controlled by d

•

Diodes and

Transistor

operate in D class (swich on/off)

•

C an L are nearly loss less !

•

Power efficiency 90%,

100% if perfect diode and transistors

•

DE in not a function of I

L

and may be small as desired as

a function of L and C

•

Drawback: E<U

From Baranowski et al.

E

If R

L

< R

Lmax

and f

R

<<F

o

dT

T

U

C

E+DE

U

1

K

I

L

I

0

Low pass
loss less filter
H(f)

R

L

load

T

dT

U

1

(t)

f

0 f

R

Fo 2Fo 3Fo

FFT [U

1

(t)]

E

U

f

FFT

E

F

f

if

f

FFT

U

dy

t

U

T

U

mean

o

R

T











<<











)

0

(

)

0

(

)

(

1

)

(

0

1

1

LC

f

f

f

f

H

R

R

1

]

/

[

1

1

)

(

2







F

o

=1/T

B.Piwakowski Analog electronics , Chapter IV Supply Systems

DC/ DC Converter with transformer ,

dT

T

U

C

E+DE

U

1

K

I

L

I

0

Low pass
loss less filter

R

L

load

V

1

Advantages
• If n <1 => E<U
• If n>1 => E<U
• IF diodes are inverted, => E<0
• Separation of grounds

n1 : n2 = n

B.Piwakowski Analog electronics ,

Chapter IV Supply Systems

Eo+DE

Uo≈max(V

1

)=

308V !

DC/DC converter
Using transformer

Uo+DU

V

1

C2

220 V

rms

+
-

I

o

Rectifier without transformer => Simplest , chipest ,solution

0

Problems and solutions:
•

« ground level » is connected wit the ground level of 220V supply

=>security problem
=>special construction (plastic housing and transformer) etc are required

•

U=308 V is generally to high comparing with E ,

=> Uo-Eo too high =>classic stabilizer efficiency is small
=> Use of DC/DC converters

B.Piwakowski Analog electronics , Chapter IV Supply Systems

Uref=5V

T

d

U

d=f(Us)

E

G +

-

DC/DC

Car 12V => USB (5V, max 500 mA

12V

5 V

DC/DC konwerter ze stabilizacją DC/ DC

Converter with stabilizer DC/DC

In car: => Same ground
DC/DC without transformer, =>simpler

B.Piwakowski Analog electronics ,

Chapter IV Supply Systems

http://www.maximintegrated.com/

DC/DC

d

E

U

T

dT

d

DC/DC konwerter jako regulator predkosci silnika
DC/DC converter used as the motor driver

I

0

R

L

Motor acts as low pass filter

B.Piwakowski Analog electronics ,

Chapter IV Supply Systems

V

1

220 V

rms

Stabilizer or DC/DC

U1

Rectifier 1

Rectifier 2

-U1

U2

U3

-U3

U4

E1

E3

-E3

-E1

E2

E4

Stabilizer or DC/DC

Stabilizer or DC/DC

Stabilizer or DC/DC

Stabilizer or DC/DC

Stabilizer or DC/DC

Analog circuits

Digital « ground »

Analog

Digital circuits

Uklady zasilania schemat ogolny
Power supply , general scheme

B.Piwakowski Analog electronics ,

Chapter IV Supply Systems

Digital circuits

supply

Analog stabilized
Supply

Analog
pulsed circuits
supply

Digital

circuits

Analog
pulsed mode
circuits

C

Eo

L

Eo1 +

De(t)

Eo1

0 « ground »

Eo2

0

Eo3

0

Eo

or simply « blocking capacity”

C

Blocking low pass filters RLC

Supply block

V

1

220 V

rms

card

card

Ogolne uwagi dotyczace konstrukcji systemow zasilania

General recommendation for supply circuits design

•

Jeden punkt polaczenia wszystkich mas

One jonction for all grounds

•

Oddzielne zasilanie dla rożnego typu obwodów

Separate supplies for different circuits

especially for analog and digital

•

Filtry blokujące na wejściu każdej z kart

blocking filter at each card enter