The document outlines a presentation for designing a variable AC and DC power supply aimed at providing a high output and low error rate for use in electrical laboratories. It details the project's aim, the method of operation including components like transformers and buck converters, and the protective measures in place. The document also discusses the advantages and disadvantages of the power supply system and future steps for enhancement.

1. Prepared by:
Ballen Ghazi Faith
Dyar Kakl Ahmed
Abdulqader Hasan Hamed
Supervisor:
Dr.Dhiadeen Mohammed
University of Kirkuk
College of Engineering
Electrical Department
2023 -2024
Presentation about :

2. PRESENTATION LAYOUT
1. Aim of project
2. Introduction
3. Power supply
4. The method of operation
5. Buck convertor
6. Auto transformer
7. Simulation & design
8. Advantage &disadvantage &using.
9. The next step of project
10. Reference

3. AIM OF PROJECT
• The main goal of this project is to Design a variable AC and DC power
supply with a high power output and lowest error rate with
protection capability ( short circuit, under voltage, over voltage,
output overcurrent, over-temperature, timeout protection).
• This power supply to be used in electrical laboratories for students to
conduct experiments with different experiments.

4. INTRODUCTION
A power supply device is an electrical device that offers electric power to an
electrical load such as laptop computer, mobile charger, TV or other
electronic devices. The main function of a power supply is to convert electric
current from a source to the voltage, current, and frequency to power the
load. in general have two part of power supply AC and DC ,Most of power
supply is used to convert Alternate current to Direct Current.

5. • linear Mode Power Supply
• Advantages for linear mode power supplies include simplicity, reliability, low
noise levels and low cost.
• EPW30-48A-E Power Module
power supply AC to DC:

6. The method of operation(LPS)
Transformer − An input transformer for the stepping down of the 230v AC
power supply.
Rectifier − A Rectifier circuit to convert the AC components present in the
signal to DC components.
Smoothing − A filtering circuit to smoothen the variations present in the
rectified output.
Regulator − A voltage regulator circuit in order to control the voltage to a
desired output level.
Load − The load which uses the pure dc output from the regulated output.

7. Power supply protection

8. Buck convertor(step down)
The buck converter, also referred to as a step-down converter, is a popular topology in
power electronics that converts a higher input voltage to a lower output voltage.The
primary advantage of the buck converter is its simplicity.
WZ5020L DC- DC Buck Converter CC CV Step-down Power Module 50V 20A 1000W

9. Operation Buck convertor(step down)
The operating principle of the buck converter involves controlled energy transfer from the input to the
output through switches, an inductor, and a capacitor. A high-side switch (usually a MOSFET or IGBT ) and
a low-side switch (typically a diode) are employed in the buck converter to control the current flow
through the inductor. By adjusting the duty cycle of the high-side switch, the average output voltage can
be regulated proportionally to the input voltage. When the high-side switch of a buck converter is
switched on, it allows current to flow through the inductor, which stores energy in its magnetic field. This
stored energy is then transferred to the output, charging the output capacitor and powering the load.
When the high-side switch is turned off and the low-side switch is turned on, the inductor's magnetic
field collapses, releasing the stored energy and maintaining the current flow to the load. The buck
converter is designed to operate within a closed-loop control system.

10. Protection Buck convertor
This type of buck convertor have following protection:
1. Under voltage protection.
2. Over voltage protection.
3. Over current protection.
4. Over capacity protection.
5. Time out protection.

11. AC Power Supply(Auto Transformer)
Auto transformer is a transformer that allows for fine adjustments to the
output voltage. variable transformer usually consists of a wiper or brush
that can be rotated across the windings to create a variable turns ratio.

12. simulation

14. INSIDE DESIGN
We get on the power source and then use two circuit breakers to protect our circuit from short circuit and over current. The
first circuit breaker give power to the charger 50V/30A and then DC power output from charger goes to the PS 1000w in
this electronic board we can take controlled voltage from 0V to 50V. Also, the 220VAC electricity goes through the second
circuit breaker to the variable transformer which we can control the output AC voltage from 0v to 50v AC.also we used AVO
display meter and auxiliary terminal to out put voltage.

15. OUTSIDE DESIGN
50 V
50 V
L
N
30CM
30CM
DC
AC
Front View
Back View
Right Side View
MCB-20A
lamp
lamp
MCB-20A
Emergency stop
10A
AV meter
Voltage meter
Ampere meter
MCB-20A

16. Result
Front view
back view

17. Advantage & disadvantage &using
This project use to following experiment:
1. Single phase motor series speed control.
2. Single phase transformer step up & down.
3. Dc generator.
Advantage :
1. Control DC voltage and current output.
2. Control AC voltage output.
3. High current out put (20A-DC & 10A-AC).
4. Low cost(200$) compare other power supply.
Disadvantage:
1. this project have not three phase terminal out put.
2. The lack of components in the Iraqi market and use of component of other
electrical appliances that are basically used for other purposes and not for
the power supply, which will be decrease efficiency and increase errors in
this project.
3. may be Decrease voltage when applying load, with ripple problem.

18. The next step of project
• Adding three phase AC to this project.
• Adding constant DC voltages such as 12v,24v,42v DC .
• Adding auxiliary resistance box.

19. Reference
• Wikipedia. (n.d.). Retrieved from https://en.wikipedia.org/wiki/Power_supply
• Hart, D. W. (2011). Power Electronics. New York: McGraw-Hill.
• https://www.monolithicpower.com/en/power-electronics/dc-dc-
converters/buck-converters
Thanks for Listening