Electrical steel for transformer core
Electricity is the lifeblood of the modern world. As the world develops and society's needs grow, so does the need to develop more efficient transformers, generators and motors. These technologies are critical to improving grid efficiency and the sustainability of the planet. The first step towards achieving these ecological and technological advances is the development of more efficient electrical steels.
Electrical steel is an important component of electromagnetic machines. It is used to make magnetic cores that help power transformers, generators, etc. It goes by many names – laminated steel, silicon steel, transformer steel and silicon electrical steel – but all of these terms have their own unique magnetism.
Electrical steel is usually manufactured in the form of cold-rolled strip, often called lamination. During the transformer core assembly process, these thin-cut laminations are stacked together to form the core.
electrical steel for transformer core
Chemical properties of electrical steel
Electrical steel is steel alloyed with iron and silicon. Silicon is the most important alloying element in electrical steel because it provides the electrical resistance in the material. This resistance decreases when eddy currents enter, thereby reducing core losses. Additionally, manganese and aluminum can be added to the material.
The purity of the material is critical. Sulfur, oxides, nitrides and carbides all reduce the steel's magnetic permeability and, over time, reduce the core's effectiveness. To reduce losses, transformer core manufacturers often use annealing furnaces to remove these harmful contaminants. Grain-oriented steel and non-grain-oriented steel Grain-oriented electrical steel
Grain Oriented Electrical Steel (GOES) is alloyed with iron and silicon and is designed to provide low core losses and high magnetic permeability.
During the development of GOES, the material had optimal magnetic properties in the rolling direction. The overall magnetic flux density of the grain-oriented material increases by 30% in the roll-in direction, but its magnetic saturation decreases. GOES are most commonly used in high-efficiency transformers, generators and motors.
Cold-rolled grain-oriented steel is referred to as CRGO. Non-grain-oriented steel
Non-grain-oriented steel is electrical steel that is not cold rolled in a specific direction to control its crystal orientation. It typically has a silicon content of 2% to 3.5%, and the magnetic properties are consistent in all directions. Its benefit is that it is much cheaper to produce and is most applicable where cost reduction is more important than efficiency improvement, which is often the case in motors and other appliances where there is no magnetic flux.
Cold rolled non-grain oriented steel is referred to as CRNGO.
