EJ2201 Electrical Machines and Drives 6.0 credits

Elektriska maskiner och drivsystem

The course focuses on electrical machines and their important role in modern society, e.g. as traction motors in electric vehicles and generators in hydro power stations.

  • Education cycle

    Second cycle
  • Main field of study

    Electrical Engineering
  • Grading scale

    A, B, C, D, E, FX, F

Course offerings

Autumn 19 for programme students

Autumn 18 for programme students

Intended learning outcomes

After completing the course, the student should be able to:

  • Describe the fundamental parts of electrical drives including converter, electrical machine and load.
  • Explain the operating principles of induction machines, synchronous machines and dc machines
  • Identify parameters in models of electrical machines
  • Use equivalent circuits to analyze electrical machines in steady state
  • Construct phasor diagrams for different loads and to use the vector method for analysis of AC machines
  • Describe the design of a simple three-phase ac winding and explain the concepts of pole number and winding factor
  • Explain the background to voltage harmonics and estimate their influence on e.g. losses in electrical machines
  • Use dynamic simulation software to analyze vector control of induction motors.

Course main content

Induction machines, synchronous machines, DC machines, salient poles, time harmonics, models for electrical machines under steady state and transient conditions, vector representation of AC machines, control of torque, speed and position for variable-speed AC and DC motor drives


  • Lectures   30 hours      
  • Tutorials  20 hours       
  • Laboratories 8 hours
  • Project  


Knowledge comparable to EJ1200 Electric Power Systems.

 English B or equivalent.

Recommended prerequisites

• Electrical circuit analysis (for example EI1110 Electrical circuit analysis, extended course or EI1120 Electrical circuit analysis for the energy and environment program)
• Electromagnetic theory (for example EI1220 Electromagnetic theory E or EI1225 Electromagnetic theory, introductory course for energy and environment)


Compendium Electrical Machines and Drives EJ2201 KTH (in Englsih).


  • LAB1 - Laboratory Work, 0.5, grading scale: P, F
  • PRO1 - Project Work, 1.5, grading scale: P, F
  • TEN1 - Written Exam, 4.0, grading scale: A, B, C, D, E, FX, F

The grading of the course (A/F) is given by the grading at the written examination (TEN1).

Requirements for final grade

Every examination part passed (LAB1, PRO1, and TEN1).

Offered by

EECS/Electrical Energy Engineering


Oskar Wallmark


Oskar Wallmark <owa@kth.se>

Supplementary information

Replaces EJ2200

Add-on studies

EJ2120 Electric energy conversion, project course

EJ2222 Design of Electrical Machines

EJ2230 Control in Electrical Energy Conversion

EJ2311 Modulation of Power Electronic Converters

EJ2420 Seminars in Electrical Machines and Power Electronics

EJ2440 Electric Transportation


Course syllabus valid from: Spring 2019.
Examination information valid from: Spring 2019.