Everyone knows that the toroidal transformer core is made of uninterrupted continuous oriented silicon steel strip. It will form a highly consistent magnetic flux guide after annealing, which can make the toroidal transformer achieve high electrical efficiency of 95%. In order to increase your understanding of silicon steel sheets, this article will briefly introduce the common knowledge of silicon steel sheets.
Silicon steel refers to an iron-silicon alloy containing 0.5% to 4.8% silicon, and is a soft magnetic material widely used in the electrical field. Silicon steel used in electrical engineering is often rolled into large sheets or strips of standard size, commonly known as silicon steel sheets, and is widely used in toroidal transformers. There are two types of silicon steel sheets: cold-rolled and hot-rolled. Among them, cold-rolled silicon steel sheets are divided into cold-rolled oriented silicon steel sheets and cold-rolled non-oriented silicon steel sheets. Toroidal transformers mostly use cold-rolled oriented silicon steel sheets. Compared with cold-rolled non-oriented silicon steel, the magnetic properties of oriented silicon steel have strong directivity. It has superior high permeability and low permeability in the direction of easy magnetization rolling Loss characteristics. The iron loss of the oriented steel strip in the rolling direction is only 1/3 of the transverse direction, the magnetic permeability ratio is 6:1, the iron loss is about 1/2 of the hot rolled strip, and the magnetic permeability is 2.5 times the latter.
The toroidal transformer cold-rolled oriented silicon steel sheet has excellent magnetic properties along the rolling direction. It not only has high saturation magnetic flux density and low iron loss in a strong magnetic field, but also has good magnetic properties in a weak magnetic field (large initial permeability). Because the cold rolling process reduces the content of impurities in the steel sheet and causes coarse grains in the steel sheet, resulting in increased magnetic permeability and reduced hysteresis loss. The core of the toroidal transformer wound by cold-rolled oriented silicon steel sheet has no air gap, so that the winding is evenly wound on the toroidal core. This structure results in small magnetic leakage and small electromagnetic radiation, without additional shielding. Used in high-sensitivity electronic equipment, such as various medical equipment.