Skip to main content

Single Phase Transformer and Applications of Single Phase Transformer


single phase transformer

Transformer is electromagnetic static electrical equipment (with no moving parts) which transforms magnetic energy to electrical energy. It consists of a magnetic iron core serving as a magnetic transformer part and transformer cooper winding serving as electrical part. The transformer is high-efficiency equipment, and its losses are very low because there isn’t any mechanical friction inside. Transformers are used in almost all electrical systems from low voltageup to the highest voltage level. It operates only with alternating current (AC), because the direct current (DC) does not create any electromagnetic induction. Depending on the electrical network where the transformer is installed, there are two transformer types, three-phase transformers and single phase transformers. The operation principle of the single-phase transformer is: the AC voltage source injects the AC current through the transformer primary winding.
The AC current generates the alternating electromagnetic field. The magnetic fieldlines are moving through iron transformer core and comprise the transformer secondary circuit. Thus the voltage is induced in the secondary winding with the same frequency as the voltage of the primary side. The induced voltage value is determine by Faraday’s Law.

Where,
f → frequency Hz
N → number of winding turns
Φ → flux density Wb

If the load is connected on the secondary transformer side the current will flow through secondary winding. Basically, the single phase transformers can operate as step up transformer or step down transformers.The main parts of a transformer are windings, core, and isolation. The windings should have small resistance value and usually they are made of copper (rarely of aluminum). They are wound around the core and must be isolated from it. Also, the windings turns have to be isolated from each other. The transformer core is made from very thin steel laminations which have high permeability. The laminations have to be thin (between 0.25 mm and 0.5 mm) because of decreasing power losses (known as eddy current losses). They have to be isolated from each other, and usually, the insulating varnish is used for that purpose. The transformer insulation can be provided as dry or as liquid-filled type. The dry-type insulation is provided by synthetic resins, air, gas or vacuum. It is used only for small size transformers (below 500 kVA). The liquid insulation type usually means using mineral oils. The oil has a long life cycle, good isolation characteristics, overload capability and also provides transformer cooling. Oil insulation is always used for big transformers.

The single phase transformer contains two windings, one on primary and the other on the secondary side. They are mostly used in the single-phase electrical power system. The three-phase system application means using three single phase units connected in the three-phase system. This is a more expensive solution, and it is used in the high voltage power system.

Applications of Single Phase Transformer

The advantages of three single-phase units are transportation, maintenance, and spare unit availability. The single-phase transformers are widely used in commercial low voltage application as electronic devices. They operate as a step-down voltage transformer and decrease the home voltage value to the value suitable for electronics supplying. On the secondary side, rectifier is usually connected to convert a AC voltage to the DC voltage which is used in electronics application.

Comments

Post a Comment

Popular posts from this blog

Shell Type Transformer: What is it? And it's Applications

D epending on the construction of its magnetic core, we can categorize transformers into two types: Shell Type Transformer Core Type Transformer Core of Shell Type Transformer We use ‘E’s and ‘L’s shape laminations to make the core of the shell-type transformer . Limb of Shell Type Transformer The core of a single phase shell type transformer is constructed with of three limbs (legs). This design increases the mechanical strength of the core. It also improves the protection of windings from external mechanical shocks. The HV and LV windings are wound around the central limb. The central limb carries the entire flux (φ), whereas the side limbs carry half of the flux (φ/2). Hence, to accommodate the flux the cross-section of the central limb is twice than that of the side limbs. The magnetic flux flows through two closed magnetic paths which decrease the core losses and hence increase the efficiency of transformer . So, shell type transformer gives more output compared to similar c
Post a Comment
Read more

Auto Transformer: What is it? (Definition, Theory & Diagram)

  W hat is an Autotransformer? An autotransformer (or auto transformer ) is a type of electrical transformer with only one winding. The “auto” prefix refers to the single coil acting alone (Greek for “self”) – not to any automatic mechanism. An auto transformer is similar to a two winding transformer but varies in the way the primary and secondary winding of the transformer are interrelated. Autotransformer Theory In an auto transformer, one single winding is used as primary winding as well as secondary winding. But in two windings transformer two different windings are used for primary and secondary purpose. A circuit diagram of auto transformer is shown below. The winding AB of total turns N 1 is considered as primary winding. This winding is tapped from point ′C′ and the portion BC is considered as secondary. Let’s assume the number of turns in between points ′B′ and ′C′ is N 2 . If V 1 voltage is applied across the winding i.e. in between ′A′ and ′C′. Hence, the voltage acro
Post a Comment
Read more

Hysteresis Eddy Current Iron or Core Losses and Copper Loss in Transformer

Losses in Transformer As the electrical transformer is a static device, mechanical loss in transformer normally does not come into picture. We generally consider only electrical losses in transformer . Loss in any machine is broadly defined as difference between input power and output power. When input power is supplied to the primary of transformer , some portion of that power is used to compensate core losses in transformer i.e. Hysteresis loss in transformer and Eddy current loss in transformer core and some portion of the input power is lost as I 2 R loss and dissipated as heat in the primary and secondary windings, because these windings have some internal resistance in them. The first one is called core loss or iron loss in transformer and the later is known as ohmic loss or copper loss in transformer . Another loss occurs in transformer, known as Stray Loss, due to Stray fluxes link with the mechanical structure and winding conductors. Copper Loss in Transformer Copper loss
Post a Comment
Read more