What is a transformer? Let's take a look together

Principle of Transformer

A transformer is a device that uses the principle of electromagnetic induction to change AC voltage. The main components are a primary coil, a secondary coil, and an iron core (magnetic core). In electrical equipment and wireless circuits, it is often used for raising and lowering voltage, matching impedance, safety isolation, etc. In a generator, whether the coil moves through a magnetic field or the magnetic field moves through a stationary coil, an electric potential is induced in the coil. In both cases, the value of the magnetic flux remains unchanged, but the amount of magnetic flux intersecting with the coil changes, which is the principle of mutual induction. A transformer is a device that uses electromagnetic mutual induction to transform voltage, current, and impedance.

The composition of the transformer

Transformer components include body (iron core, winding, insulation, lead wire), transformer oil, oil tank and cooling device, voltage regulating device, protection device (moisture absorber, safety airway, gas relay, oil conservator and temperature measuring device, etc. ) and outlet casing. Specific composition and function:

(1) Iron core. The iron core is the main magnetic circuit part of the transformer. It is usually made of stacked hot-rolled or cold-rolled silicon steel sheets with high silicon content, thicknesses of 0.35mm, 0.3mm, and 0.27mm, and 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 covered with windings; the horizontal piece is used to close the magnetic circuit.

(2) Winding. The winding is the circuit part of the transformer, which is wound with double-wire insulated flat wire or enamelled round wire. The basic principle of the transformer is the principle of electromagnetic induction. Now take the single-phase double-winding transformer as an example to illustrate its basic working principle: when the voltage U1 is applied to the primary side winding, the current I1 flows, and an alternating magnetic flux is generated in the iron core. O1, these fluxes are called the main flux, under its action, the windings on both sides induce potentials respectively, and finally drive the transformer control device.