S11  transformer cores

I. Iron Core Material

The iron core of the S11 transformer is mainly made of high-quality silicon steel sheets. Silicon steel is an iron alloy containing silicon, and this material has excellent magnetic properties. The silicon element in it can effectively reduce the hysteresis loss of the iron core, enabling the transformer to convert electrical energy more efficiently during operation.

II. Performance Characteristics

• Low Loss: The losses of the S11 transformer iron core mainly include hysteresis loss and eddy current loss. Due to the use of high-quality silicon steel sheets, its hysteresis loop is narrow and the hysteresis loss is small. Meanwhile, the silicon steel sheets have a relatively high resistivity, which can reduce the eddy current loss. As a result, both the no-load loss and the load loss of the transformer are at a relatively low level, greatly improving the operating efficiency of the transformer.

• High Permeability: High permeability means that the iron core can be magnetized more easily, allowing the magnetic field to be transmitted more effectively inside the iron core. In this way, a sufficiently strong magnetic field can be generated under a smaller exciting current, which is beneficial for reducing the current in the windings, reducing copper loss, and enhancing the electromagnetic induction ability of the transformer.

• Good Stability: Under different load conditions and changes in ambient temperature, the S11 transformer iron core can maintain relatively stable magnetic properties. This ensures the stability of the output voltage of the transformer, reduces voltage fluctuations, and improves the power supply quality.

III. Iron Core Structure

• Laminated Structure: The S11 transformer iron core usually adopts a laminated design. Silicon steel sheets are laminated one by one, and the adjacent silicon steel sheets are insulated from each other. This structure can effectively reduce the cross-sectional area of the eddy current path and further reduce the eddy current loss. Moreover, the laminated structure is convenient for processing and assembly, and the size of the iron core can be flexibly adjusted according to the capacity and voltage level of the transformer.

• Three-Phase Structure (for Three-Phase Transformers): In a three-phase transformer, the iron core consists of three limb cores and upper and lower yokes. The three limb cores are respectively sleeved with three-phase windings. This structure can balance the three-phase magnetic fields, reduce the losses caused by unbalanced magnetic circuits, and improve the three-phase balance performance of the transformer.

IV. Manufacturing Process

• Cutting and Punching of Silicon Steel Sheets: First, the coiled silicon steel sheets are cut according to the design requirements to make silicon steel sheets of appropriate sizes. During this process, the dimensional accuracy of the silicon steel sheets must be ensured to guarantee the quality of the iron core after lamination. For some silicon steel sheets with special shapes, punching operations are also required to punch holes for installing windings and other connecting structures.

• Surface Insulation Treatment: In order to prevent short circuits between silicon steel sheets and generate excessive eddy current losses, the surface of the silicon steel sheets needs to be insulated. Usually, the method of coating insulating paint or other insulating materials is adopted to maintain good insulation performance between adjacent silicon steel sheets.

• Lamination and Clamping of the Iron Core: The silicon steel sheets after insulation treatment are laminated in a certain order and manner. During the lamination process, the flatness and tightness of the laminations must be strictly controlled to avoid looseness or excessive gaps. After lamination, clamps or binding tapes are used to clamp the iron core to ensure the stability of its structure.

• Annealing Treatment (Optional): In some cases, in order to eliminate the internal stress generated during the processing of the iron core and improve the magnetic properties, the laminated iron core will be annealed. The annealing temperature and time need to be reasonably controlled according to factors such as the material of the silicon steel sheets and the size of the iron core.