Explain construction and working principle of single phase transformer.

4 Answers

Answer :

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Construction of single phase transformer: Single-phase transformer essentially consists of following components: 

i) Windings: Two windings generally of copper are placed round the core and are insulated from each other and also from the core. 

ii) Core: Magnetic core is made up of thin silicon steel laminations which act as a magnetic circuit. 


For big size transformers, tank is used to accommodate the core-winding assembly. In fact, the core-winding assembly is kept immersed in oil in the tank. The oil acts as a cooling medium and also the insulating medium. The terminals are taken out of the tank using bushings. The supply is connected to primary winding and load is connected to secondary winding. 


Working of single phase transformer: Transformer works on the principle of Mutual electromagnetic induction. When AC voltage is applied to the primary winding, it produces alternating flux in the core. This flux links with the secondary winding and according to Faraday’s law of electromagnetic induction, an emf is induced in the secondary winding and the current flows in the secondary circuit if load is connected.

Answer :

Working Principle of Transformer: -

The primary winding is connected to AC supply current starts flowing through primary winding. The primary current produces an alternating flux in the core.  These flux gets linked with the secondary winding through the core The alternating flux will induce voltage into the secondary winding according to the faraday’s laws of electromagnetic induction.

Answer :

Transformer is a static device (does not have any moving/rotating parts) 

Transformer has two windings: primary & secondary. 

Transformer works on the principle of mutual induction between two coils. 

Transformer transfers electrical energy from one circuit to another circuit with change in voltage &/or current. 

Transformer transfers electrical energy without change in frequency. 

Supply is given to primary winding & output is taken from secondary winding.

Answer :

A single phase transformers is an electrical device that accepts single-phase AC power and outputs single-phase AC.

PRINCIPLE...


The single-phase transformer works on the principle of Faraday’s Law of Electromagnetic Induction. Typically, mutual induction between primary and secondary windings is responsible for the transformer operation in an electrical transformer.

A transformer is a static device that transfers electric power in one circuit to another circuit of the same frequency. It consists of primary and secondary windings. This transformer operates on the principle of mutual inductance.


Working.......


When the primary of a transformer is connected to an AC supply, the current flows in the coil and the magnetic field build-up. This condition is known as mutual inductance and the flow of current is as per the Faraday’s Law of electromagnetic induction. As the current increases from zero to its maximum value, the magnetic field strengthens and is given by dɸ/dt.


Construction.....


A simple single-phase transformer has each winding being wound cylindrically on a soft iron limb separately to provide a necessary magnetic circuit, which is commonly referred to as “transformer core”. It offers a path for the flow of the magnetic field to induce voltage between two windings.



As seen in the figure above, the two windings are not close enough to have an efficient magnetic coupling. Thus, converging and increasing the magnetic circuit near the coils can enhance the magnetic coupling between primary and secondary windings. Thin steel laminations shall be employed to prevent power losses from the core.

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