Transformers are designed to change the voltage of the alternating current, the coordination of electrical circuits.
The transformer in most cases consists of a closed magnetic circuit (core) with windings located on it. The number of windings can be arbitrary. One of them is connected to the source of the EMF variable and is called primary. All other windings are called secondary.
Alternating current, flowing through the turns of the primary winding, induces an alternating magnetic field in it and the core. This magnetic field intersects the turns of the secondary windings and induces (induces) EMF variables in them. The magnitude of the induced EMF of the secondary windings is directly proportional to the number of turns in these windings. Therefore, the main parameter of the transformer is the transformation ratio n: n=W1/W2 or n=U2/U1 where W1 and U1 — the number of turns and the voltage of the primary winding, W2 and U2 — the number of turns and voltage of the secondary winding.
If there are more turns in the secondary winding than in the primary winding, the alternating voltage of the secondary winding will be greater than the alternating voltage of the primary winding. Such transformers are called step-up, but on the contrary — step-down.
Sources:
http://www.cromptonusa.com/Potential%20Transformers.pdf
https://www.explainthatstuff.com/transformers.html
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Great! Very useful article! What do you think about Coercive force? Coercive force the one of a important factors.
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Undoubtedly, the coercive force is one of the important characteristics when designing a transformer. To reduce it, magnetically soft materials are used, so named because of the smaller amount of energy that is required for their magnetization reversal.
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