40220742 (Analysis of Electric Machinery)

Course Name: Analysis of Electric Machinery

Course Number: 40220742

Program: Undergraduate program

Type: Elective

Credits: 2

Term Offered: Autumn

Prerequisite(s): Electric Machinery Fundamentals

Instructor(s): Xudong Sun, Shanming Wang

Textbook(s):

Xudong Sun, Shanming Wang. Analysis of Electric Machinery. Tsinghua University teaching materials. (in Chinese)

Reference(s):

P. C. Krause, O. Wasynczuk, S. D. Sudhoff. Analysis of electric machinery and drive systems (2nd Edition). Wiley-IEEE Press, 2002.

Chee-Mun Ong. Dynamic simulation of electric machinery using Matlab/Simulink. Prentice Hall PTR, 1998.

A. E. Fitzgerald, C. Kingsley, S. D. Umans. Electric machinery (6th Edition). McGraw-Hill, 2003.

Yunqiu Tang, Yihuang Zhang, Yu Fan. Dynamic analysis of AC electric machines. China Machine Press, 2005. (in Chinese)

Zhiyun Ma. Transient analysis of AC electric machines. China Electric Power Press, 1998. (in Chinese)

Jian Chen. Mathematical models of AC electric machine and drives. National Defense Industry Press, 1989.

Course Description:

The course is about the foundation of modeling and analysis methods for AC electric machines in dynamic states. It covers the coordinate transformation theory, electromechanical-energy-conversion principles, and field-circuit coupling analysis method, together with their applications to synchronous machines, induction machines, switched reluctance machines and so forth. Some projects are provided to help raise students’ ability to apply these methods to solve practical problems.

Course Objectives and Outcomes:

The chief objective of the courses is to build a strong foundation in the basic theories and methods for analyzing modern electric machines and their systems. Its emphasis has been on stimulating student’s initiative in study and enhancing their ability to analyze and solve the problems from engineering, thus laying a solid foundation for their later study and research.

The course should enable the students to do the following upon completion of it. Numbers in brackets are linked to department educational outcomes.

1.Skillfully master the basic theories and methods for analyzing typical electric machines in both steady and dynamic states, and have the ability to apply them to solve the problems arising from engineering reality. [1, 3, 5, 11]

2.Have the ability to identify, formulate, and solve the problems concerning the contemporary issues of practical electric machines and their systems. [5, 10]

3.Become proficient with computer skills for solving and analysis of electric machinery models using MATLAB/Simulink. [1, 5, 11]

4.Cultivate the ability to organize, communicate and cooperate effectively. [7]

5.Could get familiar with the process of scientific research and paper writing. [5, 6, 7, 10, 11]

Course Topics:

1.An overview of electric machinery analysis methods.

2.Mathematical model of induction machines in three-phase coordinate.

3.Coordinate transformation theory for induction machines.

4.Equations and equivalent circuits of an induction machine in d-q coordinate using per unit system.

5.Applications of coordinate transformation theory to the analysis and control of induction machines.

6.Mathematical model of synchronous machines in three-phase coordinate.

7.Park’s equations for synchronous machines.

8.Park’s equations for synchronous machines using per unit system.

9.Applications of coordinate transformation theory to analyze synchronous machines.

10.Application of MATLAB/Simulink to analyze electric machinery.

11.Electromechanical-energy-conversion principles: electromechanical-energy conversion mode and equipment, energy relationship in convention, magnetic energy and electromagnetic force.

12.Power equations of rotating electric machinery.

13.Conditions for electromagnetic torque production, general formula of electromagnetic torque.

14.Application of electromechanical-energy-conversion principles to analysis of unconventional machines such as switched reluctance machines.

15.Introduction to electromagnetic field analysis for electric machines and relevant software.

16.Field-circuit coupling analysis method and its applications.

Project(s):

Three projects are presented to the students working in groups of two or three persons. These projects cover the problems in induction machines, synchronous machines and so forth. Each group is required to give a presentation about their projects. Besides, students are encouraged to raise projects by themselves. Usually different projects are given in three successive years.

Some examples of the projects are as follows:

l  Analysis of three-phase induction motor starting

 Understand the dynamic process of induction motor starting, use the model of induction motor and simulation software (MATLAB) to analyze and compare the performance in various starting modes such as direct-on-line starting, star-delta starting, auto-transformer starting, and reactor starting, explore and design an optimum voltage-frequency curve for variable-frequency starting.

l  Analysis of asynchronous starting of a three-phase synchronous motor

 Understand the principle of asynchronous starting, use the model of induction motor and simulation software to analyze its dynamic process and find the reasonable starting method, investigate the effect of the damping winding, and seek a reasonable strategy for designing the damping winding.

l  Analysis of induction wind generators with grid faults

 Understand the basic principles of induction wind generator systems, use the model of induction generator and simulation software to analyze the dynamic process of grid voltage drop for a variable-speed constant-frequency induction wind generator system, examine the detrimental effects of the fault on the converter, and propose adequate protection measures.

Course Assessment:

  Simulation project measures, 75 points.

  An in-class presentation of the project work or a survey of the cutting-edge of electric machines, 25 points.