What Types Of Transformer Magnetic Cores Are There?

Varieties of Transformer Magnetic Cores Power transformers have primary, secondary, and tertiary windings. The transformer is driven by the magnetic flux between the windings. Magnetic cores are used in transformers to serve as a path for magnetic flux. The core can be made of a variety of materials, some of which are discussed in this article.

Materials used to make transformer cores

The magnetic core is basically a material with magnetic permeability that helps confine the magnetic field in the transformer. The following are the types of materials used to produce transformer cores:

Amorphous Steel: This is one of the popular choices for making magnetic cores in transformers. These cores are made of several paper-thin strips of metal that help reduce the flow of eddy currents. Amorphous steel cores have less loss than other cores and are easier to operate at high temperatures than standard lamination stacks. Amorphous steel cores are most commonly used in high-efficiency transformers operating at intermediate frequencies.

Solid Cores: These cores provide magnetic flux and help maintain high magnetic fields without iron saturation. Magnetic cores are not recommended for transformers operating in AC applications because the magnetic field creates large eddy currents. These eddy currents generate heat at high frequencies.

Amorphous Metals: Also known as glassy metals, these metals are glassy or amorphous. These metals are used to make high-performance transformers. The low electrical conductivity of these materials helps reduce eddy currents.

Ferrite Ceramics: Ferrite ceramics are a class of ceramic compounds made of iron oxide and one or more metallic elements. Magnetic cores made of ferrite ceramics are used for high-frequency applications. Different specifications of ceramic materials are produced to meet different electrical requirements. These ceramic materials act as effective insulators and help reduce eddy currents.

Laminated Cores: These cores have thin sheets of iron covered with an insulating layer. These insulators prevent eddy currents and confine them to narrow loops within each single laminate layer. Thinner stacks minimize eddy current effects.

Carbonyl Iron Cores: These cores are made from powdered carbonyl iron and provide stable service at various flux and temperature levels. Carbonyl iron powder cores have small iron balls coated with a thin insulating layer. These cores help reduce the effects of eddy currents at high temperatures.

Silicon Steel: Silicon steel has high resistivity. Silicon steel core provides stable performance over the years. Silicon steel provides high saturation magnetic flux density.