ECE 522 – Power Systems Analysis II

Spring 2018

Final exam solution has been posted


Time and Place          

11:10-12:25 on Tuesday & Thursday at MK419

January 11 – April 26 (about 28 lectures)



Kai Sun (Email:  Phone: 865-9743982)

Office hours:  Tuesday 3:00-4:30pm (or by appointment) at MK612

GTA: Tianwei Xia (; MK207)


Course Texts/Materials/Resources



ECE 421 (Electric Energy Systems).


Course Description

This course will cover fundamentals on power system modeling for the purposes of dynamic studies and stability control, teach the methods for analyzing main stability issues of power systems and introduce the tools for planning and operating a modern interconnected power grid to meet reliability criteria under disturbances. There will be minor programming work in MATLAB or using professional power system software. Students are also required to review literature on recommended topics to gain deeper insight on emerging techniques on power system stability and control.


Course Objectives 
Upon completion of this course, every student should have gained: 

·         An in-depth understanding of basic approaches for power system modeling, analysis and control

·         A broad familiarity with engineering categories, criteria and control measures on power system stability issues including small-signal stability, transient stability and voltage stability

·         Knowledge in emerging techniques for planning and operating modern interconnected power systems


Course Outline

·         General background on modern power systems (slides: 1, 2; Quiz 1)

o   Overview of modern power system operations and planning (NERC reliability guidelines)

o   Classification and definitions of power system stability problems


·         Power system modeling

o    Modeling on synchronous machines (Park’s transformation; equivalent circuits; classic and detailed models; equations of motion) (slides: 1, 2, 3, 4, 5)

o    Modeling on loads (static and dynamic load models; acquisition of model parameters) (slides; Quiz 2)

o    Modeling on frequency regulation (governing systems; AGC) (slides: 1, 2, 3; Quiz 3) 

o    Modeling on voltage regulation (excitation systems; var compensation) (slides: 1, 2; Quiz 4)

Midterm exam on March 20 (solution)

·         Power system stability problems and control measures

o    Small-signal stability (power oscillation in interconnected systems; power system stabilizer) (slides: 1, 2)

o    Transient stability (direct methods; numerical methods) (slides: 1, 2, 3)

o    Voltage stability (voltage collapse; analysis methods and mitigation measures)  (slides)


·         Emerging topics on grid operations and planning

o    Cascading outages (slides)

Final exam on May 4 (solution)





Due Date


·         Select one IEEE PES journal paper published in or after 2015 that studies or controls stability problems of bulk power systems (not of microgrid or distribution systems)

·         Source:  or

·         Write a 1-2 pages essay (not in the form of Q&A):

o   Title, authors, source of the paper

o   Background:

§  What stability problem is concerned? (Which IEEE categories?)

§  Why is the problem significant? (Real-world stories?)

o   Approach

§  What new approach or technique is proposed? (Outlining the idea or procedure)

§  How does the new approach perform? (Compared to other methods)

o   Remark: Any conclusions or any room for further work

Give a 5-minute presentation (3-5 slides) on your chosen paper and hand in your essay in the class of 1/23 (Tuesday).


·         Derive the flux and voltage equations and equivalnet circuits for a round rotor machine; calculate dq0 currents under a balanced disturbance (description)

·         Solution

Due on 2/8 (Thursday); hand it in before/after the class.


·         Description (generator and load modeling)

·         Solution

Due on 2/27 (Tuesday)
hand it in before/after the class


·         Problems 12.3 to 12.8 on Saadat's "Power System Analysis" book plus two additional problems (description)

·         Solution

Due on 3/9 (Friday);

hand it in in the Thursday class or directly to GTA on Friday


·         Description (voltage regulation)

·         Solution

Due on 4/3 (Tuesday)


·         Description (transient stability)

·         Solution

Due on 4/19 (Thursday)


·         Description (small signal stability and voltage stability)

·         Solution

Due on 5/1 (Tuesday)



Course Requirements


Homework:                  20% 

Quizzes:                       20% 

Course project:             20%

Exams (2):                    40% (20% each)

Total                            100% (+ 1-2% in-class participation)