Why do power transformers use silicon steel sheets as iron cores?

The use of silicon steel as the core of a transformer is primarily due to its inherent characteristics: it is a magnetic material with strong magnetic permeability. Therefore, in the current coil, it can generate greater magnetic induction intensity, which can reduce the volume of the transformer.

In addition, the hysteresis loss of the transformer core is small, which can greatly reduce the degree of heating.

In fact, the power loss of a transformer is not only reflected in the resistance of the coil, but also in the iron core. We usually refer to the power loss in the iron core as "iron loss", which is caused by two reasons: one is "hysteresis loss" and the other is "eddy current loss".

Hysteresis loss refers to the loss of iron due to the existence of magnetic hysteresis in the process of magnetization. The loss is proportional to the area enclosed by the hysteresis loop of the material. Due to the narrow hysteresis loop of silicon steel, the hysteresis loss of the iron core used in transformers is relatively small, which can greatly reduce the degree of heating.