Generators and Transformers

Subject description

The losses in the core, windings and additional losses in generators and transformers. Type of  windings (Y, D, Z). Magnetization problems of generators and transformers. Dynamic analysis of short circuits in generators and transformers.

Inrush phenomenon of generators and transformers. Various types of cooling (ONAN, ONAF, OFAF …). Attenuation of short circuits.

Basic tests of generators and transformers. Monitoring the aging of insulation in generators and transformers.
Operating conditions (isolated operation, operating on a rigid network, synchronous compensator). Oscillations in generators. Synchronous reactance. Transient reactance. Sub-transient reactance. “Per-unit” system. Generators and transformers presented by symmetrical components.

The subject is taught in programs

Objectives and competences

Acquiring in-depth knowledge of different types of generators and transformers, their properties, design features and applicability.

Teaching and learning methods

Lectures, demonstrations, work with computer tools, laboratory work, coursework, project work.

Expected study results

After successful completion of the course, students should be able to:

-present the problem of magnetization in generators and transformers,

-explain the transient phenomena in generators and transformers

-apply experiments of generators and transformers for their characterization,

– analyze short circuits within generators and transformers,

– illustrate generators and transformers with symmetric components.

-clarify the operating conditions of generators and transformers (island operation, operation on a rigid network, synchronous compensation).

Basic sources and literature

  1. Jereb Peter, Damijan Miljavec: Vezna teorija električnih strojev, Založba FE in FRI 2008
  2. Bharat Heavy Electricals Limited: Transformers, McGraw-Hill, 2005
  3. S.V. Kulkarni, S.A. Khaparde: Transformer Engineering, Marcel Dekker, Inc., 2004
  4. James H. Harlow: Electric Power Transformer Engineering, CRC Press, 2003
  5. Aa. Carlson, J. Fuhr, G. Schemel, F. Wegscheider: Testing of Power Transformers,
    1. Pro Print GmbH for ABB, Düsseldorf, 2003
  6. Ion Boldea Variable Speed Generators, Taylor & Francis, 12. dec. 2010.
  7. Juha Pyrhonen, Tapani Jokinen, Valeria Hrabovcova, Design of Rotating Electrical Machines, John Wiley & Sons, 2009.

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