The device gives the voltage by decreasing or increasing it, without changing the given frequency and power. That stationary device is called a transformer. Through the transformer, the frequency and power of one circuit are transferred to another circuit by maintaining the same frequency and power.
Why do you need a transformer?
3 phase supply systems have more advantages than single phase supply systems. Therefore, generation, transmission and distribution of 3 Phase Supply System is done nowadays. To make this supply system more efficient, the Indian standards body has fixed a standard voltage for each stage.
- Generation Voltage = 11 KV.
- Transmission Voltage = 440 KV, 220 KV
- Distribution Voltage = 132KV, 66KV, 33KV, 11KV
- Utilization Voltage = 440 V or 230 V
If you understand this voltage limit carefully, 11000 volts is generated, and the voltage directly reaching the customers is used by the customers. It is 3 phase 440 volts and single phase 230 volts.
We understand from this that only 11000 volts produced are reduced to 440 volts and 230 volts.
In this way, the AC supply system should not change its supply frequency and power while reducing the voltage or increasing the voltage. The instrument required for this is a transformer.
Why are transformers called stationary devices?
In the transformer, no part is rotating or sounding like a motor. Therefore transformers are called stationary devices.
On what principle does the transformer work?
The transformer works according to the Self or Mutual Induction element of Electro Magnetic Induction.
Meaning when another coil is held constant in a changing magnetic field. The changing magnetic lines are then cut due to the constant conductor of the Koel. And because of this, EMF is formed in a coil held constant according to the element of Ferrede’s Electro Magnetic Induction.
Simple structure of transformer
The composition of transformer mainly consists of two main parts of core and winding.
Core: It is made up of English type L type, E type, I type or non-shaped shape. These stepings are made of silicon steel from 0.35 Mm to 0.5 Mm thick.
Many such steps are insulated from each other and laminated core is made. Silicon steel is used to make the core. Because this reduces hysteresis loss. And making a laminated reduces the eddy current loss.
The primary and secondary winding is done by insulating the core on the transformer core mentioned above. The winding that is supplied is called primary winding.
The winding from which the supply is taken for the load is called secondary winding. The way the indings are insulated from the core. In the same way, primary winding and secondary winding are also insulated among themselves.
Working of transformer | How does the transformer work?
When AC supply is provided to the primary winding of the transformer. Alternating magnetic lines are then formed around the primary winding. As the magnetic lines change, they are cut off from the stationary conductor.
And primary winding consists of self-induced EMF manufacturing. The AC current flows through the primary winding, thus causing changing fluxes around the primary winding.
Primary fluxes flow through the core to reach the secondary winding. Mutual Induced EMF is created in secondary winding by cutting action between the flux and the winding turns.
Induced EMF produced according to the second law of electro-magnetic induction of ferred is proportional to the turn of winding. This means that the more turns in the winding, the more the cutting action, the more static EMF is produced.
When the secondary winding is connected to the load, the secondary circuit is completed and the current starts to flow from the winding. And thus the load is provided with electric power. This is how the transformer works.