ELK331E, Deniz Yildirim, Power Electronic Circuits

Syllabus

Course Objectives

Electrical power is widely used in every part of home and industry from milliwatts to megawatts. The main objective of power electronics is to improve the quality and utilization of electrical power. Efficient use of power will, therefore, conserve the energy resources of the world. Power electronics addresses the conversion techniques of electrical energy to achieve these goals.

Course Description

Switching circuits and basic concepts of power electronics. Diode, SCR, Triacs, GTO, BJT, MOSFET, IGBT, MCT's operational characteristics. Controlled and uncontrolled one and three phase rectifiers. DC choppers. Inverters, one and three phase inverters, pulse width modulation and voltage regulation. AC choppers. Cycloconverters. Protection and snubber circuits. Parallel and series operation operation of switches.

Course Outcomes

Students who pass this course will be able to:

Learn ideal switching elements and characteristics of various power semiconductor switches,
Analyze uncontrolled/controlled single- and three-phase rectifiers, and calculate power and harmonic content in nonsinusoidal waveforms,
Use multi-pulse rectifier topologies,
Evaluate performance of single- and three-phase AC-AC converters and various control techniques in terms of harmonic content,
Analyze buck- and boost-type (class A to D) DC-DC converters and four-quadrant operation,
Investigate power circuit topologies of single- and three-phase square-wave and modified-sine-wave inverters,
Use various modulation (control) techniques such as pulse width modulation and selective harmonic elimination.

Textbook

D. W. Hart, Introduction to Power Electronics, Prentice Hall, 1997.

Other reference books that can be helpful for this course:

Timothy L. Skvarenina, The Power Electronics Handbook, CRC Press, 2002.
Click here to download the entire book in PDF format (access limited to on-campus computers).
N. Mohan, T. Undeland, W. Robbins, Power Electronics: Converters, Applications and Design, 2nd ed., John Wiley & Sons Inc., 1995.
A. M. Trzynadlowski, Introduction to Modern Power Electronics, John Wiley & Sons Inc., 1998.
M. H. Rashid, Power Electronics Circuits, Devices, and Applications, 2nd ed., Prentice Hall, 1993.
S. J. Chapman, Electric Machinery Fundamentals, 3rd ed., McGraw-Hill, 1999.
W. Shepherd and L. N. Hulley, Power Electronics and Motor Control, Cambridge University Press, 1987

Pre-requisite(s)

There is no pre-requisite(s) for this course, however, your success in this course heavily depends on the good knowledge of the following topics:

Steady-state and transient analysis of linear electric circuits containing resistors, inductors, and capacitors.
The behavior of RLC circuits involving switches.
Solution of differential equations with initial conditions.
Phasor analysis of AC circuits, computing RMS and average values, power factor, meaning of leading and lagging power factors.
Apparent, real, and reactive powers in single- and three-phase power system.
Algebra with complex numbers, transformation from rectangular to polar coordinate and vice-versa.

The above subjects will not be covered/explained in the class - this course assumes you have sufficient knowledge of these topics. If you feel that your background on the above material is insufficient, you are advised to take a look at your circuit's and mathematic's notes and/or books.
Here is an excellent book that covers these topics:

J. W. Nillson and S. A. Riedel, Electric Circuits, 7th ed., Addison Wesley, 2004

Computer Requirement

Use of circuit simulation programs such as PSPICE, PSIM, ORCAD, Electronic Workbench, etc. may be required for assignments.

Division of Course Credit (%)

Mathematics and Basic Science ....: None
Engineering Science ...................: 100
Engineering Design .....................: None
Social Sciences .........................: None

Grading Policy

Projects (P1: 7%, P2: 8%, P3: 10%, P4: 15%)= 40% Two Midterm Exams (MT1:10%, MT2:10%) = 20% Final = 40%

A minimum of 70% attendance to the lectures (10 out of 14 lectures) are required to enter the Final Exam. Students who do not satisfy this requirement will be given a grade of VF and will not be allowed to take the Final Exam.

Exam and Project Policy

In your Project assignments, you are expected to work in a team (not necessarily) where the number of the team members cannot exceed FOUR students. You are free to select your fellow group members. Select your group members appropriately, as this may adversely affect overall time that you spent in finishing the projects. All group members must have all the required knowledge about the projects. This will definitely be questioned during the submittal process of your project.

All Project assignments include design, simulation, construction and testing of a power electronic circuit. In other words, you will have a chance to build your own circuit within the scope of the class. You can use Electrical Machines and Power Electronics Laboratory for building and testing of your supplies. Should you have any questions, consult with Teaching Assistant (TA) of the course.

You will be submitting a group report for each Project assignment. Your Project reports must obey the technical report format. Failure to comply will result in ZERO grade in report. Absolutely no exception on this matter!!

Each report must contain the following title page. Failure to comply will result in ZERO grade in report.
Absolutely no exception on this matter!!

Submittal process of Project assignment will be carried out during the Due Date. Groups will be showing their completed circuits (in Power Electronics Laboratory) to the TA who may ask certain questions to any group member about the project. All group members must be present in this submittal process. Failure to appear will result in a zero grade. Project reports must be submitted to the TA during this process.

You are also required to submit all assignments electronically in addition to paper submissions. Submittal process will take place through ITU Ninova system using your ITU username and password. There is a strict time deadline for uploading assignment solutions since system will not accept any assignments once the deadline has expired.

ALL GROUP MEMBERS MUST upload their group report. Failure to do so will result in ZERO grade from the project. Deadline time is 09:30am on the due date of project.

Your assignments must be uploaded as a single file in Microsoft Word or PDF format. No other formats will be accepted.

A grade of 0 out of 100 in assignments and/or exams implies that you were not present in the exam or in project submission.

A grade of 0.XX out of 100 in assignments implies that you copy someone else's assignment or someone else has copied your assignment.

Midterm and final exams will be open notes/open books.

DISHONESTY BEHAVIOR OF ANY KIND IN EXAMS AND/OR MINIPROJECT ASSIGNMENTS WILL NOT BE TOLERATED AT ALL. DIRECT COPYING OF SOMEONE ELSE'S WORK (OR LETTING SOMEONE TO DUPLICATE YOUR WORK) AND PRESENTING IT AS YOUR OWN WORK IS CONSIDERED AS ACADEMIC DISHONESTY. FAILURE TO COMPLY WILL RESULT IN A DISCIPLINARY ACTION.

		Weekly Lecture Subjects
		The following timetable is approximate and is given for informational purposes only. The subjects and the dates may change depending on the subject's coverage .
	Week	Subject
	1	The answer of "What is Power Electronics?" question and application areas of power electronics, classification of power converters. Ideal switch and rectifier. Semiconductor power switching devices used in power electronic circuits: Diode, bipolar junction transistor (BJT), silicon controlled rectifier (thyristor), triac, diac, gate turn-off thyristor (GTO), mosfet, insulated-gate bipolar transistor (IGBT), integrated-gate commutated thyristor (IGCT), and injection-enhanced gate transistor (IEGT). I-V characteristics, operation principles, maximum voltage and current ratings.
	2	Power Semiconductor switches continued. Gating circuits for controlled semiconductor switches. Series and parallel commutation circuits for turning-off of thyristors.
	3	AC-DC: Alternating Current - Direct Current converters (rectifiers). Single phase half-wave uncontrolled and controlled rectifiers. Operating principles (voltage and current waveshapes, analytic solutions, power factor, etc.) for resistive, resistive-inductive and resistive-inductive-constant voltage load conditions.
	4	Single phase full-wave uncontrolled, half-controlled and controlled rectifiers. Operating principles (voltage and current waveshapes, analytic solutions, power factor, etc.) for different load conditions.
	5	Rectifiers continued.
	6	Three-phase half-wave uncontrolled and controlled rectifiers, three-phase full-wave uncontrolled, half-controlled and controlled rectifiers, 12-pulse rectifiers, power factor.
	7	Three-phase rectifiers continued.
	8	AC-AC: Alternating Current - Alternating Current Converters (AC choppers). International standards that limits the maximum values of harmonics injected to the utility at the point of common coupling: IEEE 519-1992, IEC 555-2. Single- and three-phase AC choppers, phase control and burst-firing control methods, resistive and resistive-inductive load conditions. Comparison of phase control and burst-firing control methods in terms of generated harmonics and application areas. Direct frequency converters: Cycloconverters.
	9	AC choppers continued.
	10	DC-DC: Direct Current - Direct Current Converters (DC choppers). Buck type class A and boost type class B choppers operating in first quadrant. Two-quadrant operation: Class C operating in 1st and 2nd quadrant, Class D operating in 1st and 4th quadrant. Four-quadrant operation: Class E choppers
	11	DC choppers continued.
	12	DC-AC: Direct Current - Alternating Current Converters (inverters). Full-wave converters, single-phase square-wave inverters, amplitude and harmonic control at the inverter output, three-phase six-step square-wave inverter, harmonics in square-wave inverters. Description of Pulse Width Modulation (PWM) and its principles, voltage-controlled PWM inverters, harmonics in PWM inverters. Different modulation techniques for voltage-controlled PWM inverters, current-controlled voltage-source PWM inverters.
	13	Inverters continued.
	14	Inverters continued.