Important Mechanism of Electrical Transformers

Electrical Transformers

Simply defined, an electric transformer (or simply, transformer) is a static device that transfers electric power from one of its electrical circuits to another electric circuit, without any change in its frequency and without the use of any physical connection between the 2 circuits.

This article outlines how transformers work, along with its working mechanism and underlying principle.

What is a Transformer?

A transformer is a device that can receive alternative current (AC) at one voltage, and deliver the same at a different voltage. Transformer performs this voltage transformation either by stepping up (or stepping down) the AC voltage and current.

Primarily, a transformer works on the following 2 principles:

  • Principle of electromagnetism, which means that an electric current can create a magnetic field.
  • Principle of electromagnetic induction, which means that any change of magnetic field within a coil of wire can produce a voltage at the end of the coils.

The basic design of a transformer comprises of the following components:

  • Core, made of either soft iron or silicon steel.
  • Windings, which are wound around the core. The winding coil comprises:
  • The primary winding, which is connected to the main electric supply. Primary windings, when connected to a higher voltage supply, are called as high voltage windings.
  • On the other hand, primary windings, connected to a lower voltage supply, are labeled as low voltage windings.
  • The secondary winding, which is connected to the load circuit, and provides the output at the desired voltage.

For stepping-up of the transformer voltage, primary low voltage windings are used, which basically means that the number of winding turns in the secondary winding is more than that of the primary winding. Alternatively, for stepping-down of the transformer voltage, primary high voltage windings are used, which basically means that the number of winding turns in the secondary winding is lesser that of the primary winding.

The Working Principle of the Transformer

Transformers work on the principle of Faraday’s law of electromagnetic induction, which states that, “the rate of magnetic flux linkage over time is directly proportional to the induced electromotive force (or EMF) in a conductor or coil,” The AC power that flows through one of the windings produces a changing (or alternating) magnetic flux around the second winding. Due to the continuous change in the flux amplitude and direction in the first winding, the flux linkage in the second winding keeps changing, thus inducing the EMF and resulting in a current flow in the secondary winding.


Electric transformers, produced by electric transformer manufacturers in Canada, are either single phase transformers or three phase transformers. Based on their use and cooling methods, there are multiple types of electric transformers available in the market.