Fundamentals of transformer design

by H du Preez, Consultant

 

Published in: Transformers and Substations Handbook: 2014

Chapter 1: Design and manufacture of transformers - page 6

Enquiries: Email henry@hdupreez.co.za

 

Read the full article on Fundamentals of transformer design in PDF format.

 

A transformer is a static piece of equipment with a complicated electromagnetic circuit. The electrical energy is transferred from one electrical circuit to another through a magnetic field. In its simplest form a transformer consists of two conducting coils having a mutual inductance. The history of transformers goes back to the early 1880s and, with the demand for electrical power increasing, large high voltage transformers have rapidly developed.

Transformers are amongst the most efficient machines and, being static devices, they have no moving components, therefore maintenance and life expectancy is long. Transformers are necessary components in the electrical systems as diverse as distribution of multi-megawatt power from power stations to hand held radio transceivers operating at a fraction of a watt.

Transformers are the largest, heaviest and often the costliest of circuit components. The geometry of the magnetic circuit is three dimensional; this property places a fundamental restraint on reducing transformer size. The properties of available material limit size and weight reduction. High voltage transformers require specific clearances and insulation type and thickness dictate the size of the unit.

Transformers are indispensable for voltage transformation in power applications. Their ability to isolate circuits and to alter earthing conventions can often not be matched in any other way. Special designs are available to conveniently obtain isolated multi-phase supplies for six, twelve, twenty four and higher phase (pulse) rectification circuits. Transformers are essentially single-application devices designed for specific requirements.

 

Take note

  • A transformer consists of two conducting coils having a mutual inductance.
  • Transformers are the largest, heaviest and often the costliest of circuit components.
  • If used in the environment and application for which it was designed, transformers will give many years of trouble-free service.