Instructor:
Office:
E-mail:
Mojtaba Mirsalim
732 Aburayhan Building
mirsalim@aut.ac.ir
,
mmirsalim@stmarytx.edu
Electrical Machines_II (3 semester credits)
Courses Objectives:
The chief objective of Energy Conversion courses continues to be to build a strong foundation in
the basic principles of Electro-mechanics and Electric Machinery. The emphasis of the courses
has been on both physical and analytical techniques.
In many institutes around the world, two semester courses in energy conversion and a laboratory
are necessary to conform to the constraints of an electrical engineering undergraduate core
curriculum. The courses should be of sufficient depth to provide basis for understanding many
real-world electric-machinery applications and to satisfy the needs of those students who pursue
specialization in other than power area. Concurrently, mastery of the material covered in the
courses and the laboratory should prepare individuals in the electric power area with adequate
prerequisite foundation for proceeding on to elective undergraduate and more advanced graduate
courses in power systems, and electric machinery design and control.
Pre-Requisites: Electrical Machines_I
Textbook:
Mirsalim, M., Electrical Machines and Transformers, Prof. Hesabi Press, 2000.
References:
1) Fitzgerald, A. E., Kingsley, C., and Umans, S. D., Electric Machinery, Sixth Edition,
New York: McGraw-Hill, 2003.
2) Slemon, G.R. and A. Straughen, Electric Machines, Addison Wesley, 1980.
3) Chapman, S. E., Electric Machinery Fundamentals, Fourth Edition, New York:
McGraw- Hill, 2005
4) Cathey J. J., Electric Machines: Analysis and Design Applying Matlab. New York:
McGraw-Hill, 2001
5) Wildi, T., Electrical Machines, Drives, and Power Systems, New Jersey: Prentice
Hall, 2006
Ž ∞Ž
: If time permits
SYLLABUS
Sinusoidal Steady-State Circuits
Review: Average, effective values, and power
’ Phasors
’ Load definition
’ Impedances in AC circuits
’ Power flow in single-phase circuits
’ Power Flow in three-phase circuits
’ Three-phase power measurement
’ Multiple Frequency Circuits
Transformers
Introduction
Applications and the Main Types
The Ideal Transformer
’ Circuit diagram
’ Voltage and current relationships
’ Dot Polarity
1. The Practical Transformer
’ Imperfections
’ Steady-State Equations
’ Phasor Diagram for an Almost Ideal Transformer (µ≈∞)
’ Coupling Coefficient
’ Accurate Equivalent Circuits
’ Choice of Equivalent Circuits
’ Phasor Diagram for Loaded Conditions
’ Rated Values
2. Per-Unit Method
3. Test Determination of Parameters
’ Dot Polarity Test
’ Open Circuit Test
’ Short Circuit Test
’ Dc Test
4. Performance Calculations
’ Voltage Regulations
’ Losses
’ Efficiencies
5. Inrush Current
6. Autotransformer
’ V and I relationships
’ Induced and conducted powers
’ Advantages and disadvantages
7. Instrument Transformers
’ Potential transformer
’ Current transformer
8. High-Impedance Transformers
9. Parallel Operation of Transformers
’ Why and how
’ Exact equality between the transformation ratios
’ Almost equal transformation ratios
10. Three-Phase Transformers
’ Star-Star (Y-Y)
’ Delta-Delta (∆-∆)
’ Star-Delta (Y-∆)
’ Delta-Star (∆-Y)
’ Zigzag
’ Four-wire Delta
’ Open Delta
’ Tee-Tee (T-T)
’ Scott connection
11. Various Group Types
12. Cooling of Transformers
Ž ∞Ž
Asynchronous (Induction) Machines
1.
2.
3.
4.
5.
Introduction
Main Parts
Operating Principles of Induction Motors
Rotating Fields
Torque Productions in Non-Salient Machines
’ Starting (Stall) torque
’ Slip
’ Operating condition torque
’ Torque-Slip characteristics
6. Similarities between Induction Motors and Transformers
7. Accurate Equivalent Circuit Diagram
8. Operating characteristics
9. Approximate Equivalent Circuit and the Related Calculations
10. Test Determination of Parameters
11. Conventional Characteristics Curves
12. Application Considerations
13. Speed Control
’ Rotor resistance control
’ Stator voltage control
’ Stator frequency control
’ Pole changing
14. Induction Motor Starting
’ Increase of the stator impedance
’ Half of the stator winding
’ Star-Delta switch
’ Autotransformer
15. Induction Motor Stopping
’ Plugging
’ DC current
16. Single-Phase Operation
17. Linear Induction Motors
18. Magnetic Levitation
Ž ∞Ž
Grading Policy: Homework = 25%
Pop Quizzes = 5 to 10%
Midterm = 25% (closed book)
Final = 40 to 45% (one-page aid-sheet)