Introduction of special transformers and selection of materials

Special transformers refer to transformers whose materials, functions, and uses are different from conventional transformers. In addition to converting AC voltage, transformers have other uses, such as changing the frequency of power supplies, power supplies for rectifier equipment, and power supplies for welding equipment. Electric furnace power supply or voltage transformer, current transformer, etc. These transformers with special uses are generally called special transformers. Because the working conditions and load conditions of these transformers are different from those of ordinary transformers, they cannot be calculated by the calculation method of ordinary transformers.

Material selection for special transformers:

1. Iron core material: The iron core materials used in transformers mainly include iron sheets, low silicon chips, and high silicon chips. Adding silicon to the steel sheet can reduce the conductivity of the steel sheet and increase the resistivity. It can reduce the eddy current and make it The loss is reduced. The steel sheet with silicon is usually called silicon steel sheet. The quality of the transformer has a great relationship with the quality of the silicon steel sheet used. The quality of the silicon steel sheet is usually expressed by the magnetic flux density B. The B value is 6000-8000, the low silicon wafer is 9000-11000, and the high silicon wafer is 12000-16000. (The silicon steel sheets used by our company are all high silicon wafers).

2. Materials commonly used for winding transformers: enameled wire, yarn-covered wire, silk-covered wire and paper-covered wire. Commonly used enameled wire, the requirements for the wire are good electrical conductivity, sufficient heat resistance of the insulating enamel layer, and must have certain Excellent corrosion resistance. Under normal conditions, use the high-strength polyester enameled wire of the QZ type.

3. Insulation material: In the winding transformer, the isolation between the layers of the coil frame and the isolation between the windings must be made of insulating materials. The ordinary transformer frame material can be made of phenolic cardboard, epoxy board, or cardboard.