ELEC0014
Introduction to electric power and energy systems

Course objectives

This course is an introduction to electric power system engineering. It describes the principles of operation, including regulation. The main components are described and their models in steady state are derived. Three-phase short-circuits are also considered. The exercices involve small systems to illustrate various features of power systems and their operation.

Refer to the pedagogical commitment for more information.

Notes de cours

        lecture notes in French available in this PDF file

Table of contents and material

  • An introductory overview of electric power systems
           slides
  1. Powers in the sinusoidal steady state
           slides
  2. Balanced three-phase systems and operation
           slides
           exercises
  3. The "per unit" system
           slides
           exercises
  4. Some properties of electric energy transmission
           slides
           exercises
  5. Variation of loads with voltage and frequency
           slides
  6. The overhead power line (and the underground power cable)
           slides - Part 1
           slides - Part 2
           exercises
  7. The power transformer
           slides
           exercises
  8. The synchronous machine (simplified model)
  9. Frequency control
  10. Voltage control
  11. Introduction to balanced fault analsyis

Visit to ELIA training center and national dispatching

ELEC0029
Electric power systems analysis

Course objectives

This course is the continuation of ELEC0014. It is devoted to computational methods for the analysis of electric power systems of any size in steady-state conditions, in the presence of faults, in balanced and unbalanced operating conditions, respectively. Emphasis is on "system" approaches initiated in course ELEC0014. Exercises involve using a power flow computation software as well as MATLAB scripts for fault analysis.

Refer to the pedagogical commitment for more information.

Table of contents and material

  • The power flow computation
  • Power flow computation and sensitivity analysis in a simple system
  • Synchronous machine: detailed model
  • Behaviour of synchronous machine during a short circuit
  • Analysis of balanced faults
  • Analysis of unbalanced systems
  • Case study: analysis of unbalanced faults in a small distribution network
  • Introduction to Protection and Automation Philosophy

Homeworks

ELEC0047
Power systems dynamics, control and stability

Course objectives

Advanced course devoted to the dynamics, the control and the stability of electric power systems. In the first part, dynamic models of various power system components are established. They are combined into a general differential-algebraic model under the phasor approximation. In the second part, various aspects of power system (in)stability are explained. Mainly small systems are used to this purpose, although large-scale system analysis is also considered. Methods are presented for reinforcing stability or estimating how far a system operates from instability. The models and the stability notions are practiced (in hands-on sessions in class and through personal works) using RAMSES, the dynamic simulation software developed at the Univ. of Liège.

Refer to the pedagogical commitment for more information.

Table of contents and material

First part: dynamics and control

  • Dynamics of the synchronous machine
            recall:   slides from course ELEC0029     and   notes de cours (in French)
            continuation:   slides
            Homework No 1 : exercise No 2 on slide 25
            Homework No 2
  • Behaviour of synchronous machine during a short-circuit
    (a simple example of electromagnetic transients)
            slides
            the corresponding MATLAB scripts: emt.m and linmodel.m
  • The phasor approximation explained with an example
            slides
            the corresponding MATLAB scripts: phasormode.m and matA.m
  • Dynamics of the induction machine
            slides
  • Power system modelling under the phasor approximation
            slides
            Homework No 3
  • Case study: Dynamic simulation of a 5-bus system
            slides
  • Turbines and speed governors
            slides
  • Excitation systems and automatic voltage regulators

Second part: stability

  • Transient stability analysis and improvement
  • Small-disturbance angle stability analysis and improvement
  • Long-term voltage stability: fundamentals
  • Long-term voltage instability caused by large disturbances: mechanisms and countermeasures
  • The Nordic test system for voltage stability assessment
  • Long-term voltage instability caused by smooth parameter changes