Transformers are devices that use the principle of electromagnetic induction to alter alternating voltage, primarily consisting of primary windings, secondary windings, and an iron core (magnetic core). Their main functions include voltage transformation, current transformation, impedance transformation, isolation, and voltage stabilization (magnetic saturation transformers).

Transformers can be categorized by their application as follows: distribution transformers, power transformers, fully sealed transformers, modular transformers, dry-type transformers, oil-immersed transformers, single-phase transformers, furnace transformers, rectifier transformers, reactors, anti-interference transformers, lightning protection transformers, box-type transformer testing transformers, corner transformers, high-current transformers, excitation transformers, and more.

Transformers are fundamental equipment for power transmission and distribution, widely used in industries, agriculture, transportation, urban communities, and other fields. There are approximately 17 million transformers in operation in our country, with a total capacity of about 11 billion kilovolt-amperes. Transformer losses account for about 40% of the total power transmission and distribution losses, presenting significant potential for energy savings.