Transformer is a device that uses the principle of electromagnetic induction to change AC voltage. Its main components are primary coil, secondary coil and iron core (magnetic core). In electrical equipment and wireless circuit, it is often used as voltage rise and fall, matching impedance, safety isolation, etc. In the generator, no matter the coil moves through the magnetic field or the magnetic field moves through the fixed coil, the electromotive force can be induced in the coil. In both cases, the value of magnetic flux remains unchanged, but the number of magnetic flux in the intersecting chain with the coil changes, which is the principle of mutual inductance. Transformer is a device that uses electromagnetic mutual inductance to transform voltage, current and impedance
form:
The components of the transformer include the transformer body (iron core, winding, insulation and lead wire), transformer oil, oil tank and cooling device, voltage regulating device, protective device (moisture absorber, safety air passage, gas relay, oil conservator and temperature measuring device) and outgoing bushing. Specific composition and functions: [1]
(1) Iron core. The iron core is the main magnetic circuit part of the transformer. It is usually laminated by hot-rolled or cold-rolled silicon steel sheets with high silicon content, thickness of 0.35mm, 0.3mm and 0.27mm respectively, and surface coated with insulating paint. The iron core is divided into two parts: the iron core column and the transverse plate, and the iron core column is sheathed with windings; The horizontal plate is used to close the magnetic circuit.
(2) Winding. The winding is the circuit part of the transformer, which is wound with double wire wrapped insulating flat wire or enamelled round wire. The basic principle of transformer is the principle of electromagnetic induction. Take a single-phase double winding transformer as an example to illustrate its basic working principle: when the voltage U1 is added to the primary side winding, the current I1 flows, and the alternating magnetic flux O1 is generated in the iron core. These magnetic fluxes are called the main magnetic fluxes. Under its effect, the windings on both sides respectively induce the potential, and finally drive the transformer control device.
