Transformers are now commonly used in power transmission and instrumentation equipment. In these two professions, their shapes are basically similar, but their materials are significantly different. The majority of iron cores in power transmission transformers are made of thinner silicon steel sheets, characterized by a full magnetic induction intensity of about 2T for BS; The instrument transformer is made of ferrite magnetic core material, with a characteristic of BS full magnetic induction intensity of about 0.3T.

Transformers are used for communication, and there are frequent irregularities in communication, and the transformer core cannot be fully filled during the operation process. In the early days, when transmitting electricity, transformers operated at the power frequency, with a relatively low frequency of 50/60Hz, but the operating current was relatively high. The losses are mainly concentrated in copper losses, and due to the high current, it is required that the full magnetic induction intensity of the transformer core material be relatively high.

Later, it was found that the iron core of power transmission transformers made of silicon steel sheets could be satisfactory at low frequencies and under high current operation, the iron core was not full. Therefore, the main reason for using thinner silicon steel sheet iron cores in power transmission transformers is that the magnetic saturation strength is relatively high.

With the addition of electrical equipment, there is an increasing demand for different power sources and devices with higher requirements for power quality. The development of power supply has evolved from rectifier or transformer to linear power supply, and then to switching power supply. The characteristic of transformers in switch mode power supplies is that the operating current becomes very small compared to power transmission. But in order to improve the efficiency of the power supply and reduce its size. The operating frequency of the switching power transformer ranges from 20K to 200K.

If the former silicon steel sheet is used, its resistivity is very low, and eddy current loss is the primary factor in high-frequency operation. In fact, it generates severe heat, which affects the application of silicon steel sheet in switching power supplies. So, ferrite core materials are presented. Its characteristic is that the magnetic saturation strength is not high, but for switching power supplies, it is basically not full. Its key advantage is that the resistivity is relatively high compared to silicon steel sheets, the eddy current loss is reduced, the heating is not as severe, and there is basically no problem in practical application.

Article source: Transformer silicon steel sheethttp://www.cheungshun.com/