Transformer components include the tank (core, winding, insulation, leads), transformer oil, oil tank and cooling system, voltage regulating device, protection devices (desiccant, safety valve, gas relay, oil storage tank, and temperature measuring device, etc.), and outgoing line bushings. Specific composition and functions: [1] (1) Core. The core is the main magnetic circuit part of the transformer. It is usually made of high-silicon content hot-rolled or cold-rolled silicon steel sheets with thicknesses of 0.35mm, 0.3mm, and 0.27mm, coated with insulating varnish. The core is divided into core columns and shims, with the winding encased in the core columns; the shims are used for the closed magnetic circuit. [1] (2) Winding. The winding is the electrical part of the transformer, made by winding double-stranded insulated flat wire or varnished round wire. The basic principle of the transformer is the electromagnetic induction principle. Here, we use a single-phase two-winding transformer as an example to explain its basic working principle: when voltage U1 is applied to the primary winding, current I1 flows, and alternating magnetic flux O1 is generated in the core. These fluxes are known as the main fluxes, which induce electromotive forces in both windings, driving the transformer's regulating device.