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A MINOR PROJECT REPORT
on
TRANSFORMERLESS POWER SUPPLY
Submitted in partial fulfilment for the award of the degree
of
BACHELOR OF TECHNOLOGY
in
ELECTRICAL AND ELECTRONICS ENGINEERING
by
YADU NANDAN: RA1711005010207
TANAY DUGAR: RA1711005010215
ROHAN BINOY : RA1711005010217
Under the guidance of
Dr. R. SRIDHAR, M.E., Ph.D
(Professor, Department of Electrical and Electronics Engineering)
FACULTY OF ENGINEERING AND TECHNOLOGY
SRM Nagar, Kattankulathur- 603 203
Kancheepuram Dist.
NOVEMBER 2019
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BONAFIDE CERTIFICATE
Certified that this minor project report titled “TRANSFORMERLESS POWER
SUPPLY” is the bonafide work of YADU NANDAN (RA1711005010207), TANAY
DUGAR (RA1711005010215), ROHAN BINOY (RA1711005010217) who carried out
the minor project work under my supervision. Certified further, that to the best of my
knowledge the work reported herein does not form part of any other project report or
dissertation on the basis of which a degree or award was conferred on an earlier occasion
of this or any other candidate.
Signature of the Internal Guide Signature of the HOD
Dr. R. SRIDHAR, M.E., Ph. D Dr. K. VIJAYAKUMAR, M.E., Ph. D.
Professor Professor and Head
Department of EEE Department of EEE
SRM IST SRM IST
Internal Examiner 1 Internal Examiner 2
Date:
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ACKNOWLEDGEMENT
We would like to extend our gratitude to everyone who helped us in bringing this
project to fruition. We would like to thank our management for academic and technical
support. We are also grateful to the Director (E&T), Dr C. Muthamizhchelvan.
We take this opportunity to acknowledge our beloved Head of Department, Dr K.
Vijayakumar for being a constant source of inspiration and encouragement
We would like to thank our Coordinator Dr R. Sridhar for his constant support
and valuable inputs throughout our project. We are deeply grateful for their help, valuable
guidance and support. Their in-depth knowledge and vast experience proved to be the
guiding light throughout the course of our project. We also offer our thanks to our project
coordinators.
Finally, we express our very profound gratitude to our parents for providing us with
unfailing support and continuous encouragement throughout the process of researching and
writing this thesis. This accomplishment would not have been possible without them.
(YADU NADAN)
(TANAY DUGAR)
(ROHAN BINOY)
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ABSTRACT
One of the major challenges during a circuit design is to generate low-voltage DC from AC
to power the circuit. There are many methods to convert AC voltage into DC. The most
common method is the use of a step-down transformer to reduce 230V AC to a lower value
AC. This is then rectified and made ripple-free.
Even though the transformer-based power supply is efficient in providing sufficient
current, it consumes much space and makes the gadget bulky. Cost of the transformer is
also high.
To power low current demanding logic circuits and microprocessor circuits,
transformerless power supply is an ideal solution. As the name suggests it does not require
a transformer to step down voltage, instead it employs a different technique to do the task.
These power supplies have distinct advantages and disadvantages. These are cost-effective
and consume less space, so the gadget becomes handy.
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TABLE OF CONTENT
CHAPTER NO. TITLE PAGE NO.
ABSTRACT
LIST OF TABLES
LIST OF FIGURES
1 INTRODUCTION
1.1 Power supply
1.2 Types of power supply
1.2.1 AC power supply
1.2.2 DC power supply
1.3 Literature survey
1.3.1 Transformer-less power supply
1.4
