What is high-frequency transformer?
Transformers with high frequency exceeding the intermediate frequency (10 kHz) can be used in high-frequency switching power supplies as high-frequency switching power supply transformers. They can also be used in high-frequency inverter power supplies and high-frequency inverter welding machines. It is divided into several grades based on working frequency: 10kHz-50kHz, 50kHz-100kHz, 100kHz500kHz, 500kHz1MHz, and above 10 MHz.
What is core type of frequency transformer?
EI, EE, EC, U, UF, and other types of magnetic cores are used in high-frequency transformers. Choosing a of frequency transformer core should be based on the transformer’s maximum operating frequency.
Choosing a core type of high-frequency transformer should also take into account the following four factors:
- Use the existing transformer skeleton;
- The cross-sectional area, full magnetic flux density, etc., should be consistent with the circuit design;
- Structural equipment and total power and frequency requirements should be met;
- Insulation material should be safe and reliable.
How to choose the core of high-frequency transformer?
Choosing a high-frequency transformer core with a high initial permeability μi、Low coercive power Hc、A high saturation magnetic fieldBs、A low remanence rateBr、Resistivity of high magnitude
ρ and higt curie temperature point. When the high-frequency transformer is operating, the magnetic permeability is high, and the excitation current is small; A lower coercivity results in a smaller hysteresis loss; High saturation magnetic induction, low remanence, and a wide magnetic flux variation range are characteristics of high frequency transformers.
The following three factors should be considered when selecting the core structure of the high-frequency transformer that should be used:
- Consider the transfer of energy
- Take geometric constraints into account
- The ratio of the magnetic core’s cross-sectional area to the window area indicates that a multi-channel output transformer requires a larger window; Choose a magnetic core of the EE, EI, or PQ type that has a larger window and good heat dissipation; There are several types of DC/DC module power supplies available, including FEY type, FEE type, EUI type, etc.; The transformer requires a magnetic core with a relatively large cross-sectional area, and a GU-shaped core can be selected. In addition, the installation of the transformer, the ease of processing, and the cost are also important factors. It is common to use GU-shaped magnetic cores for medium and high power applications due to their large cross-sectional area and low flux leakage. They are made of domestic materials and have a low cost, but the outlet must be hand-welded.
