Low no-load loss CRGO Silicon steel flat coil iron core

The role of the transformer core: The actual transformer always works in the AC state, and the power loss is not only in the resistance of the coil, but also in the core under the magnetization of alternating current. The power loss in the iron core is usually called "iron loss", and the iron loss is caused by two reasons, one is "hysteresis loss" and the other is "eddy current loss".

Hysteresis loss is the iron loss caused by the presence of hysteresis in the process of magnetization of the iron core, and the magnitude of this loss is proportional to the area surrounded by the hysteresis loop of the material. The hysteresis loop of silicon steel is narrow, and the hysteresis loss of the core of the transformer is small, which can greatly reduce the degree of heating.

Since silicon steel has the above advantages, why not use a whole piece of silicon steel as an iron core, but also process it into sheets?

This is because the sheet core can reduce another type of iron loss, "eddy current loss". When the transformer works, there is an alternating current in the coil, and the magnetic flux it produces is, of course, alternating. This changed magnetic flux generates an induced current in the core. The induced current generated in the iron core circulates in a plane perpendicular to the direction of magnetic flux, so it is called eddy current. Eddy current losses also heat up the core. In order to reduce the eddy current loss, the iron core of the transformer is stacked with silicon steel sheets insulated from each other, so that the eddy current passes through a smaller cross-section in the narrow circuit to increase the resistance on the eddy current path; at the same time, the silicon in the silicon steel increases the resistivity of the material and also plays a role in reducing the eddy current.

The iron core used as a transformer is generally made of cold-rolled silicon steel sheet with a thickness of 0.35mm, and it is cut into a long piece according to the size of the required iron core, and then overlapped into a "day" or "mouth" shape. Logically speaking, if the eddy current is reduced, the thinner the thickness of the silicon steel sheet, the narrower the spliced piece, the better the effect. This not only reduces eddy current losses, reduces temperature rise, but also saves the material used for silicon steel sheets. But in fact, when making silicon steel sheet cores. It is not only from the above-mentioned favorable factors, because the production of the iron core in this way will greatly increase the man-hours, and also reduce the effective cross-section of the iron core. Therefore, when using silicon steel sheet to make transformer core, it is necessary to start from the specific situation, weigh the pros and cons, and choose the best size.

Transformers are made according to the principle of electromagnetic induction. There are two windings, a primary winding, and a secondary winding, wound around the closed core column. When the original winding is added with the AC power supply voltage, the original Rao group current has alternating current, and the establishment of magnetic potential, under the action of the magnetic potential, the main magnetic flux will be generated in the iron core, the main magnetic flux will pass through the iron core at the same time, and the primary and secondary windings will be closed due to electromagnetic induction in the primary and secondary windings respectively, and the induced electromotive force will be generated, as for why it can be boosted and reduced? Then it needs to be explained by Lenz's law, the magnetic flux generated by the induced current always hinders the change of the original magnetic flux, when the original magnetic flux increases, the magnetic flux generated by the induced current is opposite to the original magnetic flux, that is, the induced magnetic flux generated by the secondary winding is opposite to the main magnetic flux generated by the original winding, so the secondary winding has a low level of alternating voltage, so the iron core is the magnetic circuit part of the transformer, and the winding is the circuit part of the transformer.