Power System Dynamics and Control

Course Description

Control characteristics of energy processes in power system production and transmission facilities. Load - frequency control in power systems. Primary, secondary and tertiary load - frequency control system structure in power systems. Frequency collapse and underfreqency load shedding. Reactive power - voltage control in power systems. Voltage control devices. Voltage collapse and undervoltage load shedding. Dynamic characteristics of electric machines, network, loads and interconnections. Unit behavior during failure. Angle stability. Small signal stability and transient stability. Power system voltage stability. Long term stability. Power system stabilizers. Future Trends in ICT for Power Systems (WAMS, FACTS,...). Smart transmission grids.

General Competencies

Understanding of balance between power production and demand. Understanding of connections between load and frequency as well as voltage and reactive power. Ability for determination of most important parameters which define power system dynamic behavior.

Learning Outcomes

  1. explain principles of balancing between active and reactive power in a power system
  2. name and explain types of power system regulation
  3. differentiate interconnected power system operation form islanding power system operation
  4. explain the connection between frequency and active power and between voltage and reactive power
  5. describe the process of frequency collapse in a power system and functioning of frequency load shedding system
  6. describe the voltage collapse process in a power system and functioning of undervoltage load shedding system
  7. name and explain types of power system stability
  8. identify the most important parameters which determine dynamic behaviour of synchronous machines and describe the impact of each parametr on the power system dynamics

Forms of Teaching

Lectures

Three hours per week.

Exams

Continuously: one writing exam, final exam (writing and oral examination) and three short tests. Classical Exam: writing and oral examination at the end of semester. Results of three short tests are included.

Exercises

One hour per week. Solving numerical examples.

Laboratory Work

Two laboratory exercises in Laboratory for Power Plants and Systems: 1. Droop of hydro and thermo power plants. 2. Unit stability.

Consultations

Especcialy for seminar.

Other

Technical visit.

Seminars

Seminar.

Internship visits

Visit and lecture in National Dispatch Centre.

Grading Method

Continuous Assessment Exam
Type Threshold Percent of Grade Threshold Percent of Grade
Laboratory Exercises 0 % 4 % 0 % 4 %
Quizzes 0 % 9 % 0 % 9 %
Seminar/Project 0 % 10 % 0 % 10 %
Attendance 0 % 2 % 0 % 2 %
Mid Term Exam: Written 50 % 30 % 0 %
Final Exam: Written 50 % 30 %
Final Exam: Oral 15 %
Exam: Written 50 % 50 %
Exam: Oral 25 %
Comment:

Two points for technical visit. Points achieved on Laboratory, short tests and Seminar are admited to classical exam.

Week by Week Schedule

  1. Control characteristics of energy processes in power system production and transmission facilities. Control in power plants. Connection between load and frequency as well as voltage and reactive power.
  2. Turbine power speed characteristics. Load - frequency control in power systems. Stiffness. Speed-droop characteristic and frequency characteristics of the load. Composite governor and load characteristic. Governor dead band. Required active power for frequency control.
  3. Primary, secondary and tertiary load - frequency control system structure in power systems. Primary unit control. Automatic secondary control. Selected generation sets included in secondary control. Tertiary control and system operators.
  4. Frequency collapse and underfreqency load shedding. Most important parameters relevant for frequency deviation in the system. How operation with lowered frequency influences on turbine? Load categories. Frequency relays.
  5. Reactive power - voltage control in power systems. Voltage as power system local characteristics. Reactive power. Power system elements as reactive power loads. Most important reactive power consumers in the system.
  6. Voltage control devices. Condenser banks. Coils. Generators. Synchronous condensers. Static devices based on power electronics (SVC; STATCOM, FACTS, UPFC)
  7. Primary, secondary and tertiary reactive power - voltage control system structure in power systems. Primary control. Pilot nodes. Control zones. Automatic secondary voltage control. Coordinated automatic secondary voltage control. Tertiary control.
  8. Dynamic generation unit commitment in power plants (active and reactive power group control). Multi machines power plant. Dynamic characteristics of units. Speed of response. Forcing.
  9. Dynamic characteristics of electric machines, network, loads and interconnections. Inertia constant. Total mechanical constant. Characteristics of load. Parallel operation in interconnection.
  10. Unit behavior during disturbance. Influence of system disturbance on turbines, generators and auxiliary systems.
  11. Angle stability. Equal area criterion. Swing equation.
  12. Small signal stability and transient stability. Effects of excitation system. Critical time criteria.
  13. Power system voltage stability and voltage collapse. P-V curves. Bifurcation point. Static (predictors and correctors) and dynamic methods. Voltage stability indices.
  14. Long term and midterm stability. Inter area oscillations.
  15. Inteligent control system (WAMS). Smart transmission grids.

Study Programmes

University graduate
Electrical Power Engineering (profile)
Theoretical Course (1. semester)

Literature

S. Tešnjak, I. Kuzle (2009.), (f-P) i (U-Q) regulacije u EES-u i Dinamika EES-a, Zavodska skripta, FER-ZVNE
J. Machowski, J.W. Bialek, J.R. Bumby (2008.), Power System Dynamics: Stability and Control, John Wiley & Sons, Ltd., Chichester, UK
P. Kundur (1994.), Power System Stability and Control, McGraw-Hill, USA
E. Mariani, S.S. Murthy (1997.), Control of Modern Integrated Power Systems, Springer-Verlag, London, UK
K.R. Padiyar (2004.), Power System Dynamics: Stability and Control, Anshan Limited, Tunbridge Wells, UK

Exercises

Laboratory exercises