Power Quality

Course Description

Power Quality definition. European standards and recommendations. Harmonics. Voltage variations and flickers. Voltage unbalance. Power factor. Power quality measurements. Measuring instrumentation and equipment. Applied measures for power quality improvement. Including Power quality in distribution planning and operation.

General Competencies

Understanding of the power quality problems. Knowledge about disturbance sources and their influence on the end users. Ability to perform in-situ measurements and practical skills to analyze measuring results. Proposing measures to improve power quality.

Learning Outcomes

  1. define the term power quality
  2. explain the security of supply
  3. describe parameters of voltage quality
  4. select legislation and standards regarding the power quality
  5. recognize the impact of harmonics on supply quality
  6. describe merasuring procedure of voltage quality
  7. explain measures to improve the quality of power supply

Forms of Teaching


Lectures supported by Power Point presentations.

Grading Method

Continuous Assessment Exam
Type Threshold Percent of Grade Threshold Percent of Grade
Homeworks 50 % 20 % 50 % 20 %
Attendance 50 % 10 % 50 % 10 %
Mid Term Exam: Written 50 % 30 % 0 %
Final Exam: Written 50 % 40 %
Exam: Written 50 % 70 %

Week by Week Schedule

  1. Introduction to power quality. The quality of delivery. Voltage quality. The responsibilities of providers and consumers of electricity. Standards of power quality.
  2. Terms and definitions. Voltage transients: impulsive and oscillatory. Long-duration voltage variations: overvoltage, undervoltage, interruptions, Short-duration voltage variations; interruptions, sagsy, Voltage unbalance. Voltage distortion. Frequency variations
  3. Voltage drops and sags. Sources of voltage variations and interruptions, Equipment sensitivity to voltage sags.
  4. Transient overvoltages. Capacitor switching. Switching overvoltages. Lighting. Ferro resonance.
  5. Harmonic distortion. Voltage and current distorrtion. Sources of harmonic distortion. Influence on end users.
  6. Harmonic distortion measurement. Harmonic evaluation on the utility system. Harmonic evaluation for end users. Monitoring principles and harmonic eleimination. Harmonic filters. Standards applied to harmonic distortions.
  7. Long-term voltage variations. Voltage regulation principles. Tap changers. Static VAR compensators. Capacitor applications. Power factor corretions.
  8. Power quality estimation. RMS voltage variation indices. Harmonic indices.
  9. Power quality measuring equipment. Multimeters, data-logers, harmonic analyzers.
  10. Applied measures for power quality improvement. Grounding and wiring. Power factor correction.
  11. Electomagnetic interference. Power frequency electrical and magnetic fields. High frequency Interfference.
  12. Static electricity. Measurement of static voltages. Relative humidity measurement. Discharge of static potentials.
  13. Power quality contracts. RMS variations agreements. Harmonic agreements. Quality insurance.
  14. Power quality monitoring. Including power quality in distribution planning and development of distribution networks.
  15. Power quality economic. Influence of deregulated market.

Study Programmes

University graduate
Electrical Power Engineering (profile)
Recommended elective courses (3. semester)


M. H. J. Bollen; (2000.), Understanding Power Quality Problems: voltage sags and interruptions, IEEE Press
C. Sankaran (2002.), Power Quality, CRC Press
R.C. Dugan, M. F. McGranaghan, S. Santoso, H. W. Beaty (2002.), Electrical Pover System Quality, McGraw Hill Professional
Alexander Kusko, Marc T. Thompson (2007.), Power quality in electrical systems, McGraw-Hill Professional
Barry W. Kennedy (2000.), Power quality primer, McGraw-Hill Professional


ID 34511
  Winter semester
L1 English Level
L1 e-Learning
30 Lectures
0 Exercises
0 Laboratory exercises
0 Project laboratory

Grading System

90 Excellent
80 Very Good
70 Good
60 Acceptable