Transformer is a machine that helps in transforming the power from one circuit to another without any frequency change. This post will discuss what is Transformer, How it works, it’s parts, various types with brief introduction, applications, advantages and disadvantages.

What is Transformer

It is an electrical equipment that works on the Induction principle. It is basically used in electricity supply to transmit electrical energy from one voltage level to another.

Image 1- Trans (1)

Fig. 1 – Introduction to Transformer

They are dated back to the 1880’s. Post discovery of Induction propertie, the evolution of the Transformer took place making it more efficient and smaller in size. In 1830, Otto Blathy, Miksa Deri, Karoly Zipernowsky of the Austro-Hungarian Empire were the first gentlemen who designed the Transformers. They experimented and used it commercially.

Main Parts of Transformer

It consists of three main parts. They are:

  • Core
  • Primary Winding
  • Secondary Winding

Core

It creates path for Magnetic Flux.

Primary Winding

It receives input from AC source.

Secondary Winding

It receives energy from the primary winding and conveys it to the load.

Main parts of Transformer

Fig. 2 – Main Parts of Transformer

How does Transformer Work

To understand how it works, let us consider single-phase Transformers as shown in the Fig. 3 below. One or more electrical conductors of insulated copper or aluminium are wound around the vertical section of the magnetic core called ‘limbs’. When Voltage V1 is applied to the Primary Winding, an AC voltage V2 occurs in the Secondary Winding by Mutual Induction.

The electrical conductors in the Core are magnetically coupled and Energy is transmitted through this Electrical/ Magnetic coupling. The ratio between the number of turns of the coils is equal to voltages at ‘0’ load. The number of turns of the Primary Winding is termed as N1 and similarly the number of turns of the Secondary Winding is referred to as N2.

Thus, Transformer Equation is:

image

Working of Transformer

Fig. 3 – (a) Schematic diagram of Single Phase Transformer (b) Circuit Diagram of Single Phase Transformer

Types of Transformers

Depending on the purpose and the objective of the Transformers, there can be various types of them as mentioned below:

  • Step Up and Step Down Transformers
  • Three Phase and Single Phase Transformers
  • Power, Distribution and Instrument Transformers
  • Two Winding and Auto Winding Transformers
  • Outdoor & Indoor Transformer
  • Oil Cooled & Dry Type Transformers
  • Core Type, Shell Type and Berry Type Transformer

Step Up and Step Down Transformer

These kinds of Transformers usually help during the voltage fluctuations. They stabilize the power supply and distribute them normally.

Step up and down

Fig. 4 – Step Up & Step down Transformers

Read in Detail about Step Up Transformer, How it Works, Construction, Applications & Advantages

 

Read in Detail About Step Down Transformer, Working, Equation, Types, Advantages & Disadvantages

Three Phase and Single Phase Transformer

The Three Phase power system is used due to its cost effectiveness than the Single Phase Transformers. However, looking at the size and the ease for transportation, the Single Phase Transformers are suitable. They are further divided into:

  • Core Type
  • Shell Type

Core Type

In this type, both the Winding (Primary and Secondary) are placed on the side limbs and has two magnetic circuits.

Shell Type

This type has one magnetic circuit and winding are placed on the central limbs of the Transformer.
Single Phase and Three Phase

Fig. 5 – Single Phase and Three Phase Transformer

Power, Distribution and Instrument Transformer

Power Transformers are meant for stabilizing the power voltage fluctuations. This is used during the high power load duration.

Distribution Transformers are meant for the commercial or the residential purpose. This has a good efficiency level with 50% full load capacity and can operate for 24 hours with good voltage regulation.

Instrument Transformers includes Current Transformers and Potential Transformers, which are used to reduce the voltage. They provide electrical isolation between high voltage power circuit and measuring instruments.

Distribution Transformer (1)

Fig. 6 – Distribution Transformers

Two Winding and Auto Winding Transformer

These are the Transformers used depending on the ration of the voltage. Two winding transformers are utilized with the ratio is greater than 2 while the later is used at the time of voltage ratio being less than 2.

Winding Transformer

Fig. 7 – Winding Transformer

Outdoor & Indoor Transformers

As the name suggests, the Outdoor Transformers are installed for outdoor equipment. The Indoor Transformers are usually for office or residential purposes.

Indoor outdoor trans

Fig. 8 – (a) Outdoor Transformers (b) Indoor Transformers

Oil-Cooled & Dry-Type Transformers

The difference between both the Transformers is the cooling system. While the Oil-Cooled requires  oil and the Dry-Type Transformer uses air as the cooling medium.

Image 9 - Trans

Fig. 9 – Dry-Type and Oil-Cooled Transformers

 Applications of Transformers

Some of the applications are listed below:

  • Due to the feature of equal transmission and distribution of electrical power, the Transformers are used in power plants, industrial plants and the traditional electric utility companies.
  • They are used for the purpose of controlling heavy power supply.
  • They are used as step up/down devices in power transmission.

Advantages of Transformers

The advantages are mentioned below:

  • Its foremost advantage is controlling and stabilizing the voltage transmission.
  • It does not require any starting time.
  • It is highly efficient with less capital investment and low maintenance.
  • They provide isolation to the ground.
  • There are no moving parts in Transformers.

Disadvantages of Transformer

There are some drawbacks in the performance of Transformers. Some of them are mentioned below.

  • Due to its material in the making of the iron core, there is wastage in the current flow.
  • It gives out lot of heat which requires cooling. This creates a break in the flow of the current.
Also Read:
DC Motor- Classification, Working Mechanism, Applications & Advantages
Power Factor - Power Triangle, Types, PFC, Applications, Advantages
How to Make Simple Inverter at Home - Step by Step