Parts of a transformer

The basic parts of a transformer are the core, the primary winding, and the secondary winding. Apart from these, there are various other components such as insulation, transformer oil, cooling arrangements, protection relays, enclosure, etc present in larger transformers. Let’s discuss the working principle of a transformer before diving into the topic. Transformer – Principle … Read more

K-factor rated transformers

What are K-factor rated transformers? K-factor rated transformers are capable of withstanding the heating effects caused by harmonic load currents. They are specially designed for non-linear harmonics generating loads. It is defined in the ANSI/IEEE C57.110 standard. Electronic circuits, switched-mode power supplies and semiconductor switches draw a large amount of non-linear current causing distorted current. … Read more

What is magnetization current in a transformer?

A certain amount of current is drawn by a transformer from the source connected to it primary even when no load is connected to its secondary. A part of this current is used to create flux in the transformer core. This current is known as magnetization current. Definition of magnetization current Magnetization current can be … Read more

Magnetization inrush current in a transformer

Transformer inrush current or magnetization inrush current is a transient input current drawn by a transformer during its energization. Depending on several factors, the magnitude of the magnetization inrush current can be somewhere from 5 to 30 time the rated full load current of the transformer. This happens even when the transformer is energized at … Read more

Transformer kVA calculator – Based on load

Whenever the available AC source voltage differs from the load voltage, we use transformers to increase or decrease the voltage levels. The calculation of kVA rating is crucial while sizing or selecting a transformer for a specific application. Here is a simple transformer kVA calculator, that can help you determine the required kVA rating of … Read more

Transformer noise (Humming sound of transformers)

Noise is an unpleasant, unwanted and annoying sound. Transformer noise, quite commonly known as the ‘humming sound or buzzing sound’ of transformer, is one of the major problems with large transformers. The noise from the transformers installed close to a residential area or an office could annoy the tenants. Why do transformers make noise? Even … Read more

Open circuit test & Short circuit test in transformers

Open circuit test and short circuit test are conducted to determine the core loss, copper loss, and equivalent circuit parameters of a transformer. In this article, in addition to the tests mentioned in the title, we will also discuss the polarity test and Sumpner’s test. Normally transformers are tested at no-load. Transformers can be tested … Read more

Equivalent circuit and Phasor diagram of a transformer

In order to understand the equivalent circuit of a transformer, we suggest you read Ideal transformer first and then come back and continue from this point. What is an equivalent circuit of a transformer? Equivalent circuit of a transformer is a schematic representation of a practical transformer that shows all electrical parameters such as winding … Read more

Ideal Transformer

A transformer is an AC device used to step down or step up voltages. To visualize the current flow and other circuit properties of a transformer, certain assumptions are made, and a conceptual circuit is made, which we can call an ideal transformer. In fact, no transformer is ideal. What is an Ideal transformer? A … Read more

Types of electric transformers

You might have come across various types of transformers in your daily life either knowingly or unknowingly. This article illustrates various transformer types. Before getting into classification, here is a brief introduction to the basic principle of the operation of transformers. Transformers are devices used to transfer power between two AC circuits. It works on … Read more