12V to 120V DC - DC Converter using Power Electronics for higher efficiency and reliable operation

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MINOR PROJECT REPORT

ON

12 V TO 120 V DC-DC CONVERTER

Submitted by

Shah Rinal Upendrakumar

(Roll No. 13MEEP23)

Under the guidance of

Dr. P. N. Tekwani

Department of Electrical Engineering

Institute Of Technology

Nirma University Of Science & Technology

Ahmedabad 380060

April 2014

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INSTITUTE OF TECHNOLOGY

NIRMA UNIVERSITY OF SCIENCE & TECHNOLOGY

CERTIFICATE

This is to certify that Ms. Shah Rinal Upendrakumar (13MEEP23) has succesfully

submitted her Minor Project Report entitled 12 V TO 120 V DC DC

CONVERTER towards the partial fulfillment of the requirements in Master of

Technology (Electrical Engineering) in the field of Power Electronics, Machines &

Drives of Nirma University of Science & Technology is the record of work carried out

by him under my supervision & guidance. The Work submitted has in my opinion

reach a level required for being accepted for examination. The results embodied in

this minor project work to the best of my knowledge have not been submitted to any

other University or Institution.

Dr. P. N. Tekwani

(Head Of Department & Project Guide)

Department of Electrical Engineering



Ahmedabad 380060

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Statement by the Candidate

I wish to state that work embodied in this project titled 12 V TO 120 V DC DC

CONVERTER forms my own contribution to the work carried out under the

guidance of Dr. P. N. Tekwani (Guide) at Institute Of Technology, Nirma University

Of Science & Technology. This work has not been submitted for any other Degree or

Diploma of any University/Institute. Wherever, references have been made to

previous works of others, it has been clearly indicated.




April 2014

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Acknowledgment

Foremost, I wish to acknowledge and thank my guide Dr. P. N. Tekwani. His kind

hearted guidance throughout my studies has been an invaluable contribution to my

academic and professional development. For this I am truly grateful.

I wish to thank the faculty members of Electrical Engineering Department. Their

interaction and advice has certainly improved the quality and direction of my project.

Certainly, I must acknowledge my parents. They have loved and supported me

longer than anyone, regardless of my faults.

April, 2014




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Abstract

The focus of this work is show DC-DC converter works on two phases, first phase is

of the inverter and the second phase is of rectifier and filter block. Circuit is simple,

IC NE555 and IC CD4013 acts for inverting phase and the bridge diode works for

rectifier and filter phase. Step up transformer was used to step up AC voltage

between inverter and rectifier & filter block.

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Contents

Acknowledgment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv

Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v

List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii

1 Introduction

1.1 What is DC - DC Converter. . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.2 Types of DC DC Converter . . . . . . . . . . . . . . . . . . . . . . . . . 3

2 Introduction to Circuit

2.1 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2.2 Circuit diagram . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3 Basic Component related to DC-DC converter

3.1 List of the Component. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3.2 Component description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

3.2.1 IC NE555 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

3.2.2 IC CD4013 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.2.3 Transistor TIP122 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4 Circuit Description

4.1 Detail description of the circuit . . . . . . . . . . . . . . . . . . . . . . . . 12

4.2 My results from the circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

5 Conclusion & Future Directions . . . . . . . . . . . . . . . . . . . . . . . . . 15

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

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List of Figures

2.1 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2.2 Circuit diagram . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.2.1 IC NE555 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

3.2.2 IC CD4013 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.2.3 Transistor TIP122 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

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CHAPTER 1

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Introduction

1.1 What is DC - DC Converter

DC-DC converters are electronic devices used whenever we want to change DC

electrical power efficiently from one voltage level to another. Theyre needed because

unlike AC, DC cant simply be stepped up or down using a transformer. In many ways, a

DC-DC converter is the DC equivalent of a transformer.

Typical applications of DC-DC converters are where 24V DC from a truck battery must

be stepped down to 12V DC to operate a car radio, CB transceiver or mobile phone;

where 12V DC from a car battery must be stepped down to 3V DC, to run a personal

CD player; where 5V DC on a personal computer motherboard must be stepped down

to 3V, 2V or less for one of the latest CPU chips; where the 340V DC obtained by

rectifying 240V AC power must be stepped down to 5V, 12V and other DC voltages as

part of a PC power supply; where 1.5V from a single cell must be stepped up to 5V or

more, to operate electronic circuitry; where 6V or 9V DC must be stepped up to 500V

DC or more, to provide an insulation testing voltage; where 12V DC must be stepped up

to +/-40V or so, to run a car hifi amplifiers circuitry; or where 12V DC must be stepped

up to 650V DC or so, as part of a DC-AC sine wave inverter.

In all of these applications, we want to change the DC energy from one voltage level to

another, while wasting as little as possible in the process. In other words, we want to

perform the conversion with the highest possible efficiency.

An important point to remember about all DC-DC converters is that like a transformer,

they essentially just change the input energy into a different impedance level. So

whatever the output voltage level, the output power all comes from the input; theres no

energy manufactured inside the converter. Quite the contrary, in fact some is inevitably

used up by the converter circuitry and components, in doing their job.

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1.2 Types of DC DC Converter

There are many different types of DC-DC converter, each of which tends to be more

suitable for some types of application than for others. For convenience they can be

classified into various groups, however. For example some converters are only suitable

for stepping down the voltage, while others are only suitable for stepping it up; a third

group can be used for either.

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CHAPTER 2

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Introduction to Circuit

2.1 Block diagram

2.2 Circuit diagram

Input (DC Voltage)

Output (DC Voltage) Inverter

(DC to AC)

Rectifier and filter

(AC to DC)

Step up transformer

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CHAPTER 3

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Basic Component related to DC-DC converter

3.1 List of the Component

Component Name Description

IC NE555 Single Timer

IC CD4013 Dual D-Type Flip-Flop

Resistor

R1

R2

R3

R4

R5 and R6

100 K Ohm

18 K Ohm

3.3 K Ohm

1 K Ohm

1.5 K Ohm

Capacitor

C1

C2

C3

C4

330 nF

100 F / 25 V

220 F / 250 V

220 nF / 250 V

Transistor (TIP122 NPN)

Q1 and Q2 Darlington Power Transistors (NPN)

Transformer 0 V - 120 V

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3.2 Component description

3.2.1 IC NE555

555 is a very commonly used IC for generating accurate timing pulses. It is an 8pin

timer IC and has mainly two modes of operation: monostable and astable. In

monostable mode time delay of the pulses can be precisely controlled by an external

resistor and a capacitor whereas in astable mode the frequency & duty cycle are

controlled by two external resistors and a capacitor. 555 is very commonly used

for generating time delays and pulses.

Fig. 3.2.1 Pin connection of IC NE555

Applications

Precision Timing

Pulse Generation

Time Delay Generation

Sequential Timing

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3.2.2 IC CD4013

The CD4013 dual D-type flip-flop is a monolithic complementary MOS (CMOS)

integrated circuit constructed with N- and P-channel enhancement mode transistors.

Each flip-flop has independent data, set, reset, and clock inputs and Q and Q outputs.

These devices can be used for shift register applications, and by connecting Q output

to the data input, for counter and toggle applications. The logic level present at the D

input is transferred to the Q output during the positive-going transition of the clock pulse.

Setting or resetting is independent of the clock and is accomplished by a high level on

the set or reset line respectively.

Fig. 3.2.2 Pin connection of IC CD4013

Applications

Automotive

Data terminals

Instrumentation

Medical electronics

Alarm system

Industrial electronics

Remote metering

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3.2.3 Transistor TIP122

Features

Designed for general-purpose amplifier and low speed switching applications

RoHS Compliant

Fig. 3.2.3 Pin connection of Transistor TIP122

B Base

C Collector

E Emmiter

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CHAPTER 4

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4.1 Detail description of the circuit

The circuit is very simple which converts 12V DC to 120V DC.

Circuit works in two phases and three stages. First phase is of basic inverter and the

second phase is of rectifier and filter bridge. First stage is of inverting 12V DC to 12V

AC, second stage is of transforming 12V AC to 120V AC and the last one is of

rectifying and filtering the 120V AC to get pure 120V DC.

IC NE555 operating at frequency of 100Hz and can be adjusted using R1.

Output of IC NE555 is coupled to the clock input of IC CD4013 which is a CMOS

dual D flip - flop.

IC CD4013 divides the 100Hz pulse train from IC NE555 into two 50Hz pulse trains

which are 180 degree out of phase and are available at Pin 1 and Pin 2 of IC

CD4013.

When Pin 1 is high, transistor Q1 conducts and current flows through the upper half

of T1s primary winding.

When Pin 2 is high, transistor Q2 conducts and current flows through the lower half

of T1s primary winding.

As a result a 120V voltage will be induced in secondary of T1.

This voltage is rectified using bridge D1 to produce 120V DC output.

C2 is the input DC filter.

C3 and C4 are output filter.

5 A fuse can be added in series to the 12V supply line.

T1 can be 9-0-9V/250 V/3A mains transformer.

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4.2 My results from the circuit

.

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CHAPTER 5

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Conclusion & Future Directions

For converting 12V DC to 120V DC we need to convert the 12V DC to 12V AC through

inverter and then it should be step up using tap changer transformer. This tap changer

transformer increases voltage to 120V AC and this AC voltage is then converter into

120V DC through filter and rectifier. This can also be done using DC transformer.

This was a very simple circuit which shows how DC voltage can be increase or

decrease in the circuit. On the near future we can go ahead with this idea to make

Boost Converter, Buck converter, Buck-Boost converter and Cuk converter. Even more

complex circuits can be made using this concept.

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REFERENCES

[1] http://www.circuitstoday.com/12v-to-120v-dc-dc-converter

[2] http://www.engineersgarage.com/sites/default/files/555.pdf

[3] https://www.futurlec.com/4000Series/CD4013.shtml

[4] http://html.alldatasheet.com/html-pdf/4811/MOTOROLA/MJ3001/257/1/MJ3001.html

[5] http://www.jaycar.com.au/images_uploaded/dcdcconv.pdf

[6] http://html.alldatasheet.com/html-pdf/239668/TAITRON/TIP122/293/1/TIP122.html

Dr. P. N. TekwaniCERTIFICATEDr. P. N. Tekwani(Head Of Department & Project Guide)

Documents

12V to 120V DC - DC Converter using Power Electronics for higher efficiency and reliable operation