In the traditional design of high-frequency transformers, due to the limitations of magnetic core materials, its operating frequency is low, generally around 20kHz. With the development of power supply technology, the miniaturization of power supply system, high-frequency and high power ratio has become an eternal research direction and development trend. Therefore, it is a key factor to reduce the volume of power supply and to improve the power output ratio.
As the most important part of switching power supply, HF Transformer has the following advantages over traditional frequency transformer:
The high-frequency transformers made of ferrite materials have the characteristics of high conversion efficiency and compact volume, while the traditional power transformer works under 50Hz, which requires a larger cross-sectional area when outputting the same powers, which leads to large transformer size, is not conducive to the miniaturization design of power supply, and the power conversion efficiency is lower than switching power supply.
The computer uses the switching power supply generally uses the Half-bridge power conversion circuit, the work two switch transistor turns the conduction to produce the 100kHz high frequency pulse wave, then through the high-frequency Transformer carries on the step-down, the output low voltage alternating current. In this circuit, the maximum current of the switching tube is limited to the size of the power output power (usually applied to the MOS tube of 300W power supply, and some power supply even uses the switch tube with a resistance to 10A), and the turn number ratio of each winding coil of the high-frequency transformer determines the output voltage. Due to the high frequency of work, the requirements of component quality and wiring are very high.
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