Transformer Construction

In summary: This difference is due to the frequency of the voltage that is induced in the secondary, which is different in step up and step down transformers.
  • #1
Hardik Batra
130
5
WHY in step up transformer, the number of turns are less in primary and copper wire is thick. Whereas in secondary number of turns are more and copper wire is thin.

In step-down transformer the situation is reversed.

I want the reason for this?
 
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  • #2
Fewer turns -> lower voltage -> higher current at the same power -> thicker cables required
 
  • #3
For in step up transformer, the frequency of the A.C. Voltage induced in the secondary has the frequency as that of the voltage in primary-----confusing why?
 
  • #4
Why do you expect the frequency to change?
The magnetic field oscillates with the same frequency as the coils - they cannot have a different frequency.
 
  • #5
how the voltage be increase in step up transformer?
 
  • #6
More turns -> higher voltage

Those two are proportional to each other.
 
  • #7
Your mean that more turn --> more resistance --> from v = IR --> more voltage ?
 
  • #8
Hardik Batra said:
For in step up transformer, the frequency of the A.C. Voltage induced in the secondary has the frequency as that of the voltage in primary-----confusing why?

How could it be a different frequency? 1. What possible mechanism could cause it and.
2. Which frequency would it choose to be?

What's confusing about that, if the only conclusion must be that it's the same.
 
  • #9
Hardik Batra said:
Your mean that more turn --> more resistance --> from v = IR --> more voltage ?
Did you think of looking up transformers / transformer theory on Wiki? You could avoid all these odd questions by just reading about it.
 
  • #10
Step up transformers are frequently used in SMPS for audio amplifiers in cars for example. The 12V from the battery cannot deliver much energy through a 4 Ohm load. Here comes the frequency you might be wondering about. In such SMPS the DC voltage from the battery is "sliced" into pulses by some electronics. This pulsed voltage is has a frequency at several 100 kHz. Thus the transformers are small and efficient with a few turns of very thick wire at the primary side, and a thinner (But still relatively thick) wire on the secondary side. The resistance in the windings are often less than 0.001 Ohm - on both sides, even though the secondary winding might have 10 times the resistance, but still very low. These power supplies (SMPS stands for Switch Mode Power Supply) are much more efficient than 50Hz transformes which is designed to transfer as much energy as the smaller high frequency transformer.

Maybe more information than you asked for...

Vidar
 

What is a transformer?

A transformer is an electrical device that is used to transfer electrical energy between two or more circuits through the process of electromagnetic induction. It is commonly used to increase or decrease the voltage level of an alternating current (AC) electrical supply.

What are the main components of a transformer?

The main components of a transformer include a primary coil, a secondary coil, and a core. The primary coil is connected to the input voltage and produces a magnetic field when an alternating current passes through it. The secondary coil is connected to the output voltage and the changing magnetic field induces an alternating current in this coil. The core is a ferromagnetic material that helps to concentrate and direct the magnetic field between the two coils.

What are the different types of transformers?

The two main types of transformers are step-up transformers and step-down transformers. Step-up transformers increase the voltage level, while step-down transformers decrease the voltage level. Other types include auto-transformers, isolation transformers, and instrument transformers.

How are transformers constructed?

Transformers are typically constructed with laminated iron cores and copper wire coils. The core is made up of multiple layers of thin iron sheets that are insulated from each other. The primary and secondary coils are wound around the core and separated by insulation. The entire assembly is then enclosed in a protective casing.

What factors affect the construction of a transformer?

The construction of a transformer is affected by factors such as the voltage and current ratings, frequency, and type of application. The material and size of the core, as well as the type and number of windings, are also important considerations. The operating conditions, such as temperature and environment, can also impact the construction of a transformer.

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