This ppt describe the following about DC-DC Converter Introduction Overview of DC-DC converter Basic Principle Software Simple demo with MATLAB Evolution of DC-DC converter Career path and Job Opportunity

1. DC-DC Converter
By
Dr T Porselvi
Sri Sairam Engineering College

2. Content
❖ Introduction
❖ Overview of DC-DC converter
❖ Basic Principle
❖ Software
❖ Simple demo with MATLAB
❖ Evolution of DC-DC converter
❖ Career path and Job Opportunity

3. Introduction
DC-DC converter converts a fixed DC voltage
to a variable DC voltage
It can be of Linear or Switching DC converter
Fixed DC
Voltage
Variable DC
Voltage
Linear converter do the conversion with the help
of resistive drop, whereas switching converter
uses switches for the conversion

4. Overview of DC-DC switching
converter
● DC-DC switching converters are Power
Electronics converters that convert fixed DC
voltage to variable DC voltage
● It can step down or step up the input DC
voltage
● Conversion is done at higher switching
frequency, to reduce ripple content
● It has high conversion efficiency
● Operated either in non-isolated mode or
isolated mode
● It can handle power from very low to very high
value

5. Classification of Switching DC-DC
Converter
Switching DC-DC
Converter
Hard Switching Soft Switching
Zero Current
Switching
Isolated
Non Isolated
Sepic
Buck-Boost
Boost
Buck
Full bridge
Push pull
Forward
Flyback
Cuk
Zeta Half bridge
Zero Voltage
Switching
Type C (Class C)
Type B (Class B)
Type A/ Class A
Type D (Class D)
Type E (Class E)
Luo

6. Applications
APPLICATIONS OF
DC-DC CONVERTER
Source:ethraa-
a.comcv
Source: forbes.com
Source: fuelsandslube.com
Source:
walmart.com
Source: wired.com
Source:
howtomechatronics.co
m
Source:windsystems
mag.com
Source:
favpng.com

7. Principle of operation with step
down converter
● Principle is explained with the help of simple
step down converter, where a DC input voltage,
a switch, and a load is present.
● When the switch is closed, the load is
connected to input and is disconnected when
the switch is opened.
● The output voltage is equal to input voltage
when the load is connected to DC source and is
equal to zero if not connected

8. Principle of operation
vo= 0
Load
When switch is open
vo= vin
Vin vo
Load
When switch is
closed
vo
Vin

9. Principle of operation
Vi
n
t
Vo
t
t<0
Vi
n
t
Vo
t
TO
N
0<t<TON
Vi
n

10. Principle of operation
Vi
n
t
Vo
t
TO
N
TON<t<TOFF
Vi
n
t
Vo
t
TO
N
TO
FF T
T<t<T+TON
T+T
ON

11. Principle of operation
Vo
t
TON TOFF T T+TON
Average output voltage (VDC) is
obtained as
Where is duty ratio
Where Vin =Vs

12. Principle of operation
Since the output voltage is of pulsed (chopped
form), this is also called as DC Chopper
The output is connected to the load, through L
and C to obtain the ripple free output voltage.
Control Techniques - TIme Ratio Control and
Current Limit Control

13. Control Techniques
Time Ratio Control (TRC)
1. Fixed Frequency Control/ Pulse width
Modulation
2. Variable Frequency Control/ Frequency
Modulation
Current Limit Control (CLC)
Imin
Imax
TO
N
TOF
F
t
i
CLC

14. Software for Power Electronics
Source:
plexim.com
Source:
tech.rochester.e
du
Source:
powersimtech.c
om
Source:
bdars.org.au
Source:
davidvirunurm.
com

15. MATLAB-Simulink
❖ Matrix Laboratory that uses
a matrix based language
❖ Simulink is a graphical
programming environment,
which can be used for
simulating the circuits, with
the help of inbuilt
models/blocks
❖ Very easy to construct and
simulate the circuits,
circuitdigest.
com

16. Simple Demo with MATLAB
Let us consider a Buck converter/Buck
regulator
vs vo
Control
Circuit
+
_
+
_
Vref
D
S
L
C R

17. Modes of Operation
Mode I
vs vo
+
_
D
L
C R
Where k=(TON/T) =>
TON=kT
Where ∆I=Imax-Imin
Where ∆I=Imax-Imin
(1)

18. Modes of Operation
Mode II
vs
vo
+
_
D
L
C R
Where TOFF = T-TON
= (1-k)T
(2)

19. Equating 1 and 2
=
Design Equations for given ripple
current and voltage
VS 100v
L 0.01H
C 0.006F
R 10 Ω
f 1kHz
k 50%

20. Simulation Circuit-open loop

21. Simulated Output Waveform
Input
Voltage
Output
Voltage
Inductor
Current

22. Simulated Output Waveform(expanded)
Input
Voltage
Output
Voltage
Inductor
Current

23. Simulation Circuit-closed loop

24. Simulated Output Waveform
Input
Voltage
Output
Voltage
Inductor
Current
Controller
Output

25. Evolution of DC-DC Coverer
Vibrators
● They were initially used before the invention
of power semiconductor devices for DC-DC
conversion
● An electromechanical device that converts
DC into pulsed DC. Used for low power
applications
Dynamotor
● Motor-Generator set coupled together to
form a single unit
Voltage Divider
● Using potentiometer, variable DC voltage
can be produced
en.wikipedia.or
g
radiomuseum
.org
en.wikipedia.or
g

26. Evolution of DC-DC Converter
After, the evolution of DC converter in 20th
century, there have been many topologies of
the same which are grouped into six
generations, as follows
1)Classical or traditional converters (First generation)
2) Multi-quadrant converters (Second generation)
3) Switched component converters (Third generation)
4) Soft-switching converters (Fourth generation)
5) Synchronous rectifier converters (Fifth generation)
6) Multi-element resonant power converters (Sixth generation)

27. Evolution of DC-DC Coverer
Fundamental Circuits( Buck, Boost, Buck Boost),
Developed Circuits (Luo, Cuk, SEPIC, Tapped
Inductor), Transformer (Froward, Flyback, Push-Pull,
Zeta), Voltage lift(+ve,-ve output Luo, Modified P/O Luo,
Double output Luo), Super Lift (+ve and -ve output
Super Lift Luo, +ve and -ve Output Cascaded Boost),
Ultra Lift Luo Converter
1)Classical or traditional
converters (First
generation)
Transformer type Converter, Developed (Multi
Quadrant Luo Converter)
2) Multi-quadrant
converters (Second
generation)
Switched Capacitor Converter (Two and four
quadrant SC Luo, Multi lift Push Pull Luo),
Switched Inductor Converter (Transformer Type,
Four Quadrant switched inductor Luo converter)
3) Switched component
converters (Third
generation)

28. Evolution of DC-DC Coverer
ZCS-QRC(Single to Four Quadrant ZCS-Luo),
ZVS-QRC (Single to Four Quadrant ZVS-Luo),
ZTC(Single to Four Quadrant Zero Transition Luo)
4) Soft-switching converters
(Fourth generation)
Ftat transformer SRC, SRC with active clamp
circuit, Double Current SRC, ZCS SRC, ZVS
SRC
5) Synchronous rectifier
converters (Fifth generation),
Two Elements, Three Elements (ㄫ-CLL), Four
Elements (Double gamma-CL, Reverse Double
Gamma CL)
6) Multi-element resonant
power converters (Sixth
generation)

29. Opportunities
● Automobile Industries (Electric Vehicle)
● Battery Charging and Management System
● Research Opportunity
● Renewable Energy Sectors
● Smart Grid and Microgrid Technologies
● Power Supply Design
● Power and Energy Sectors

30. Thank You