The actual three-phase 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 alternating current magnetization. When the three-phase transformer is working, there is an alternating current in the coil, and the magnetic flux it generates is of course alternating.
Used as the core of the three phase transformer EI lamination, generally use 0.35mm thick cold-rolled silicon steel sheet, cut it into pieces according to the size of the required core, and then overlap into "Japanese" or "mouth" Glyph. This not only reduces the eddy current loss, reduces the temperature rise, but also saves the silicon steel sheet. However, in fact, when manufacturing a three phase transformer EI lamination, it is not only based on the above advantageous factors, because the iron core is produced in this way, the working time is greatly increased, and the effective cross section of the iron core is also reduced.
What is the voltage boost and buck of the three-phase transformer? It is necessary to explain the magnetic flux generated by the induced current, which always hinders the change of the original magnetic flux, and the magnetic flux generated by the induced current when the original magnetic flux increases. Contrary to the original magnetic flux; therefore, the secondary winding has a low-level alternating voltage, so the iron core is the magnetic circuit portion of the transformer, and the winding is the circuit portion of the transformer.