1. From Lecture1 vi , ii vo , io Power Processor Controller Source Load
Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
From Lecture1
Power Processor
Controller
Load
Measurement
Reference
POWER
INPUT
OUTPUT
vi , ii
vo , io
Source
Introduction to Power Electronics
Lecture 2

2. Why do we need power converters?
Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
Converters
Why do we need power converters?
Power sources and loads come in various types of forms.
We need a power converter to transfer the power from the source to the load while changing the form of the power.
Introduction to Power Electronics
Lecture 2

3. Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
The main task of power electronics is the conversion of one form of electrical energy to another.
This process involves the conversion of voltage and current in terms of magnitude or RMS values, the change of frequency, and the number of phases.
Power electronic components doing such conversions are referred to as converters.
Introduction to Power Electronics
Lecture 2

4. Converters are used in many different power and voltage ranges.
Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
Converters are used in many different power and voltage ranges.
The spectrum of converting electrical power ranges from a few mW to several 100 MW.
The voltage range extends from a few volts to several 10 kV or even 100 kV.
Current ratings extends from mA to kA.
Introduction to Power Electronics
Lecture 2

5. Types of electric power
Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
Types of electric power
AC Power
DC Power
Direct Current
Alternative Current V
DC Voltage Source/ Load t
Introduction to Power Electronics
Lecture 2

6. Types of electric power
Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
Types of electric power
AC Power
DC Power
Direct Current
Alternative Current
AC wall power
photovoltaic (PV)
Introduction to Power Electronics
Lecture 2

7. Four basic types of power converters
Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
Four basic types of power converters
AC-DC
AC Source --- DC Load
Rectifier
Examples: Laptop Charger
Symbol:
AC input
DC output
Introduction to Power Electronics
Lecture 2

8. Four basic types of power converters
Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
Four basic types of power converters
DC-DC
DC Source --- DC Load
Switching mode power supply (SMPS)
Portable battery pack
Symbol
DC input
DC output
Introduction to Power Electronics
Lecture 2

9. Four basic types of power converters
Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
Four basic types of power converters
DC-AC
DC Source --- AC Load
Inverter
PV-to-Grid System
Symbol
DC input
AC output
Introduction to Power Electronics
Lecture 2

10. Four basic types of power converters
Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
Four basic types of power converters
AC-AC
AC Source --- AC Load
AC Chopper:
Common light-dimmer circuit.
Wind Power System
Symbol
AC input
AC output
Introduction to Power Electronics
Lecture 2

11. Islamic University of Gaza Faculty of Engineering
Electrical Engineering Department
Introduction to Power Electronics
Lecture 2

12. Important aspects in conversion of electrical energy
Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
Important aspects in conversion of electrical energy
Costs.
Life time and reliability.
Quality of voltage and current (e.g. voltage accuracy (ripple content), harmonics of voltage and current, control dynamics etc.).
Efficiency.
Losses (losses are not only an issue of energy consumption, but also because of getting rid of the heat).
Volume, weight (espy. for mobile applications).
Introduction to Power Electronics
Lecture 2

13. Some examples of applications of power electronic systems:
Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
Some examples of applications of power electronic systems:
Power supplies for electronic home appliances, office, for telecommunication equipment and for personal computers or computer servers.
Converters for motor drives to allow speed-variable operation of electrical drives (e.g. machine tools, conveyor drives, industrial drives, pumps and fans).
Electrical wind turbines.
Photovoltaic systems.
Supplying a single-phase Hz railway grid from 3-phase, 50 Hz national power grid.
Supply of electric arc furnaces.
Lightening control.
Audio amplifiers.
Introduction to Power Electronics
Lecture 2

14. Converters & Applications of power electronics
Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
Converters & Applications
of power electronics
Introduction to Power Electronics
Lecture 2