Single Phase vs. Three Phase Transformers


A transformer refers to electromagnetic static electrical equipment that turns magnetic energy into electronic energy. It is mainly made of two things magnetic core and transformer copper winding. Here, the magnetic iron core works as a transformer part and the transformer copper winding works as an electrical part.

Difference Between Single Phase Transformer and Three Phase Transformer

The usage of transformer is seen in almost every electrical systems including low and high voltage level. It works only with alternating current as the direct current is incapable of creating any electromagnetic induction. Transformers are mainly classified into two categories based on the electrical network in which the transformer is installed- three phase transformer and single phase transformer.

The single phase transformer consists of mainly two windings; one is on primary side and the other on the secondary side. On the other hand, the three- phase system application defines the usage of three single phase units attached in the three phase system. Three phase transformers are comparatively more expensive and it is used in high power system.

Single phase transformer application

  • The benefits that three phase units offer include maintenance, transportation and the availability of spare unit
  • These single phase transformers are commonly used as electronic devices in commercial low voltage application
  • They play the role of a step down voltage transformer and reduced the value of voltage to the extent that is suitable for electronic supplying.
  • When it comes to turning the AC voltage into the DC voltage which is generally used in electronics application, a side rectifier is connected.

Three-phase transformers

Three phase transformers are generally used to step up and step down the high voltages in different steps of power transformer system.

Advantages of three phase transformers

  • Three phase transformers are easy to install
  • They are comparatively lighter and smaller
  • They consume less space for installation
  • Highly efficient
  • Less expensive as compared with three units of single phase transformer

Read more about advantages and disadvantages of three phase transformer.

The main difference between single phase and three phase transformers

In case of single phase power transformer, power lines are treated as an input source. However, only one primary and one secondary windings are available to transform the voltage. So it is clear that the single phase transformer uses these two windings for changing the voltage. Single phase transformers have different models depending on horsepower range, taps, dimensions and shipping weight.

On the other hand, the working process of the three phase transformer is different. For the proper functioning of a three phase transformer, it needs to have three windings or coils connected in the proper sequence to the suit with the incoming voltage. Then it turns the incoming voltage into the voltage that is required to maintain proper polarity and phasing.

What are the advantages of choosing three phase transformer over single phase transformer?

  • Increased efficiency- three phase motors provide higher outcomes than in smaller size than the single phase systems.
  • Constant power supply- at one side, single phase motor is a DC operated system that provides pulsating power delivery. On the other hand, three phase power is constant that is perfectly suitable for demanding applications.
  • Affordability- three phase transformers offer better affordability than single phase transformer due to their quick and powerful nature.
  • Easy parallel operation function- initiating parallel operations is easier with three phase transformers than single phase transformers

So it is clear from the above mentioned points that three phase transformers are more efficient than single phase transformers.