Power transformers are indispensable components in electrical systems, responsible for converting electrical energy from one voltage level to another to meet the requirements of various electrical devices. Among the constituent parts of a power transformer, the iron core can be likened to the "heart," serving as a critical magnetic circuit component. Typically comprised of high-silicon-content hot-rolled or cold-rolled silicon steel sheets stacked together and insulated with paint, the iron core, along with the coils wound around it, forms a complete electromagnetic induction system, facilitating the transmission and conversion of electrical energy.

Working Principle of the Iron Core in Power Transformers

In terms of its working principle, the iron core's magnetic conductor acts as the transformer's magnetic circuit. It serves as a connecting bridge that converts electrical energy from the primary circuit into magnetic energy, which is then transformed back into electrical energy in the secondary circuit, acting as the medium for energy conversion.

Functions of the Iron Core in Power Transformers

Its primary functions include securing and supporting the transformer windings while providing a pathway for as much magnetic flux as possible. As alternating current flows through the transformer windings, it generates an alternating electromagnetic field. The iron core, based on the principle of electromagnetic induction, conducts this magnetic field, thereby enhancing the transformer's transformation ratio and efficiency.

Classification of Iron Cores in Power Transformers

The surface of the iron core is typically coated with a thin layer of oxide to prevent eddy current losses. Depending on their shape and structure, transformer iron cores can be classified into various types, including E-type, I-type, and C-type, as well as triangular and pentagonal ring-shaped cores.

The diversity of iron cores also serves as a basis for classifying transformers. Depending on how the windings are arranged within the iron core, transformers are categorized as core-type transformers and shell-type transformers. Furthermore, based on the number of phases and capacity of the iron core, power transformers can be classified as single-phase transformers and three-phase transformers.

Applications of Iron Cores

In addition to power transformers, iron cores find wide-ranging applications in inductors and magnetic materials. Within inductors, iron cores can enhance their inductance and quality factor, enabling better energy storage. Iron cores in magnetic materials enhance the magnetic circuit's permeability, thereby augmenting the intensity and stability of the magnetic field.