Large Power Transformers

What is a large power transformer?

A device that uses the principle of electromagnetic induction to change the AC voltage. The main components are the primary coil, the secondary coil and the iron core. In electrical equipment and wireless circuits, it is often used as a large-scale machine device for raising and lowering voltage, matching impedance, etc.

How large power transformers work?

The working principle of large transformers is based on the principle of electromagnetic induction. A transformer has two sets of coils, a primary coil and a secondary coil. The secondary coil is outside the primary coil. When the primary coil is connected to alternating current, the transformer core generates an alternating magnetic field, and the secondary coil generates an induced electromotive force. The turns ratio of the coils of the transformer is equal to the voltage ratio.

For example: the primary coil is 500 turns, the secondary coil is 250 turns, the primary is connected to 220V AC, and the secondary voltage is 110V. Transformers can step down as well as step up. If the primary coil has fewer turns than the secondary coil, it is a step-up transformer, which can step up a low voltage to a high voltage.

How does a large transformer change voltage?

Transformers have a special parameter for changing voltage: the transformation ratio.

The transformation ratio of a transformer expresses the relationship between the number of turns of the primary winding and the number of turns of the secondary winding of the transformer. From the transformation ratio, you can see whether a transformer is a step-up transformer, a step-down transformer, or a 1:1 transformer.

Transformer ratio = primary winding turns / secondary winding turns.

A transformation ratio less than 1 is a step-up transformer, indicating that the number of turns in the primary winding is less than the number of turns in the secondary winding.

A transformation ratio greater than 1 is a step-down transformer, indicating that the number of turns in the primary winding is greater than the number of turns in the secondary winding.

It can be seen from the working principle of the transformer that the current enters from the primary winding and flows out from the secondary winding. As the current direction of the incoming alternating current is constantly changing, a magnetic field that changes synchronously with the current is generated. As the magnitude and direction of the magnetic field are constantly changing, a current is induced in the secondary coil. Because the voltage across each turn of the coil is equal, the more turns of the secondary coil, the higher the voltage output from the secondary coil.

If the primary coil has more turns than the secondary coil, the voltage on the secondary coil will decrease, which is a step-down transformer; conversely, if the primary coil has fewer turns than the secondary coil, the voltage on the secondary coil will decrease Step up, this is the step-up transformer.

The role of large transformers

1. Ensure the safety of electricity consumption and meet the needs of various electrical appliances for electricity.

2. Use a transformer to reduce the high voltage.

3. The transformer also has the function of transforming the current.

4. The transformer also has the function of transforming impedance.

The main functions of the transformer are: voltage transformation, current transformation, impedance transformation, isolation, voltage regulation (magnetic saturation transformer), etc.