The working principle of the transformer (illustration, schematic explanation, understand at a glance)

How it works

Transformer is a device that transforms AC voltage, AC current and impedance. When AC current flows through the primary coil, AC magnetic flux is generated in the iron core (or magnetic core), which induces a voltage (or current).

Basic Components

The components of dry-type transformer include body (iron core, winding, insulation, lead wire), oil-type transformer consists of transformer oil, oil tank and cooling device, pressure regulating device, protection device (hygroscopic device, safety air passage, gas relay), oil conservator and temperature measuring device, etc.) and outlet bushing.

1, iron core

The iron core is the main part of the magnetic circuit in the transformer.It is usually composed of hot-rolled or cold-rolled silicon steel sheets with high silicon content and thicknesses of 0.35 mm, 0.3 mm, and 0.27 mm, which are coated with insulating paint on the surface.

The iron core is divided into two parts: the iron core column and the horizontal piece. The iron core column is sheathed with windings; the horizontal piece is used to close the magnetic circuit.

The basic form of iron core structure has two types: core type and shell type.

2. Winding

The winding is the circuit part of the transformer, which is wound with double-wire insulated flat wire or enameled round wire.

How Transformers Work

Take a single-phase transformer as an example. The single-phase transformer has two coils wound together on a closed iron core, as shown in the figure on the right. The coil connected to the power supply is called the primary coil, and the coil related to the primary coil is called the primary coil.The marking symbols of each quantity are marked with angle code 1 in the lower right corner, such as U1, I1, etc., and the coil of the load necklace is called the secondary coil, and the marking symbols of each quantity related to the amount are marked with the angle code 2 in the lower right corner, such asU2, I2, etc.

The working principle of this transformer is: when the primary winding of the transformerWhen the alternating voltage u1 is applied, an alternating current i1 is generated in the primary winding, and this current generates an alternating magnetic flux Φ in the iron core, because the primary and secondary windings are on the same iron core, so when the magnetic flux Φ passes throughWhen passing through the secondary winding, the induced electromotive force e2 (ie, the transformer voltage) is generated on the secondary side of the transformer.The magnitude of the induced electromotive force in the transformer is proportional to the number of turns of the coil, the magnitude of the magnetic flux and the frequency of the power supply.