Course detail

Electrical Machines

FEKT-BPC-ESBAcad. year: 2024/2025

The course focuses on the principles, design, and operation of electrical machines, essential for modern mobility, electrical engineering, and industrial applications. The introduction covers the fundamentals of magnetism and their equations, followed by a detailed analysis of transformers, including their construction, operating principles, and real-world characteristics. The next section is dedicated to rotating electrical machines, such as asynchronous and synchronous machines, with a focus on torque production, generating rotating magnetic fields, windings, operational characteristics, and control methods. It also addresses synchronous machines with salient poles and permanent magnets. The course incorporates modern trends in the application of electrical machines for transportation electrification.

 

Language of instruction

Czech

Number of ECTS credits

Mode of study

Not applicable.

Entry knowledge

Student should have been able to:
-explain and define basic terms magnetic field, electric field, magnetic field, circuits with lumped and distributed parameters,
- solve DC, AC and magnetic circuits,
- solve three phase AC circuits,
- define the terms work and energy,
- describe and explain basic properties soft and hard magnetic materials.

Rules for evaluation and completion of the course

Laboratory - 30 points
Final Exam - 70 points 

Aims

To acquaint the students with the principle of operation and performance of transformers, induction machines, DC machines and synchronous machines. The theoretical knowledge are proved in laboratory excerscises
Subject graduate should have been able:
- describe main parts of electric machines,
- know classes of insulation and electrical machines costruction,
- describe construction of transformer,
- explain transformer losses,
- understand and explain single and multiphase transformer operation,
- calculate parameters of transformer equivalent circuit from no-load and short – circuit tests,
- draw and explain phasor diagrams of transformer at no load, at short circuit and generally loaded.
- transformer winding connection and phasor diagram for different hour angle,
- explain and calculate transformer voltage regulation,
- describe and explain construction and principle of operation of induction machine with wound rotor and with squirrel cage,
- describe revolving magnetic field generation,
- define basic kinds of AC machine windings,
- sketch curve of magnetic field of AC winding distributed in more slots,
- draw equivalent induction machine circuit diagram, derive torque equation and draw torque - speed characteristic ,
- describe connection of induction motor into public utility network and speed control,
- describe construction and principle of operation of single phase induction motor,
- describe principle operation and construction of nonsalient synchronous machine,
- draw simplified circuit diagram, derive torque equation and draw phasor diagram,
- explain synchronous generator operation with isolated load and with public utility network, use phasor diagram for explanation,
- explain synchronous compensator principle of operation,
- describe DC machine construction and principle of operation,
- describe basic types of DC machine windings,
- derive torque and induced voltage equations,
- explain properties of DC motors and generators,
- describe construction and explain principle of operation of AC single phase commutator machines.

Study aids

Not applicable.

Prerequisites and corequisites

Not applicable.

Basic literature

Fitzgerald,Kingsley,Kusko::Electric Machinery,McGraw-Hill
Hrabovcová, V., Rafajdus, P.: Elektrické stroje. Teória a príklady, EDIS ŽU v Žiline, ISBN: 978-80-554-0101-0 (CS)
Měřička,Haňka,Voženílek.::Elektrické stroje,ČVUT Praha
O'Kelly:Performance and Control of Electrical Machines,McGraw-Hill
P. C. Sen: Principles of Electric Machines and Power Electronics, ISBN: 9781118078877 (EN)
Stephen Umans: Fitzgerald & Kingsley's Electric Machinery 7th Edition, ISBN: 978-0073380469 (EN)

Recommended reading

Not applicable.

Elearning

Classification of course in study plans

  • Programme BPC-SEE Bachelor's 2 year of study, summer semester, compulsory

Type of course unit

 

Lecture

39 hod., optionally

Teacher / Lecturer

Syllabus

  1. Introduction and Motivation, Magnetism in Electrical Machines 
  2. DC Machines
  3. Transformer – Construction, operating principle, and ideal transformer.
  4. Transformer – Real transformer, equivalent circuit, basic equations, and three-phase transformers. Per unit system.
  5. Rotating Electrical Machines – Introduction, torque production, and generation of a rotating magnetic field.
  6. Rotating Electrical Machines – Windings of AC rotating machines.
  7. Asynchronous Machine – Construction, operating principle, and equivalent circuit.
  8. Asynchronous Machine – Phasor diagram and operational characteristics. Starting three-phase asynchronous motors from the mains, speed control, and single-phase asynchronous machines.
  9. Synchronous Machine – Operating principles, construction, and phasor diagrams.
  10. Synchronous Machine – Theory of smooth-rotor machines. Torque characteristic, synchronous machines operating with independent loads and in parallel with the grid.
  11. Synchronous Machine – Synchronous machines with salient poles and permanent magnets.
  12. Modern Trends in the Development of the Electrical Machines
  13. Reserve/Revision of Material; KT2 – Rotating Electrical Machines 

Laboratory exercise

10 hod., compulsory

Teacher / Lecturer

Syllabus

  •  Safety policies for working in the laboratory. Introduction to the laboratory – practice in circuit assembly
  • L1 – DC Machines
  • L2 – Transormers
  • L3 –Induction machines
  • Reserve measurement

Fundamentals seminar

16 hod., compulsory

Teacher / Lecturer

Syllabus

  1. N1 – Magnetic circuits and magnetism in electrical machines, DC machines
  2. N2 – Transformers
  3. N3 – Torque production, generation of a rotating magnetic field, and windings of AC electrical machines
  4. N4 – Asynchronous machine
  5. N5 – Synchronous machine
  6. N6 – Reserve/Revision of the material
 

Elearning