In the electronic products we come into contact with every day, we can find a large amount of magnetic core components, among which is the heart of the switching power supply module – serial rs232 to wifi converter the switching transformer. Nowadays, electronic products in daily life have more and more stringent requirements on the appearance of ultra-small and ultra-thin products, and the high-frequency switching power supply, which is the heart of the energy source of these electronic products, has the advantages of high efficiency, good temperature and small size. Therefore, many electronic products are high-frequency switching power supplies, as practitioners in the electronics industry, they have to understand the transformers of switching power supplies.
Switching Power Module Transformer
A transformer is a device that uses the principle of electromagnetic induction to exchange current. Its main components include primary coils, secondary coils, and iron cores.
Transformer components
In the electronics profession, transformers are often seen, and the most common ones are used in power supplies for voltage conversion and isolation:
①: Transformer can be divided into step-up and step-down, and most switching power supplies are step-down. Such electronic products are usually used in desktop power supplies, notebook adapters, mobile phone chargers, TV power supplies, rice cookers, refrigerators, induction cookers, power supplies, etc. These are all AC inputs that pass through a rectifier bridge, rectified and filtered by a large capacitor to obtain a high voltage direct current.
②: Boost is generally used in inverter power supply or DC-DC line, there is an emergency power supply, the battery 12V is converted to 220V output, and it is used for power supply equipment.
③: The isolation of high-frequency switching transformers is required by safety regulations, in order to ensure the safety of electrical equipment. In the case of AC input, the switching transformer must have a safe distance to achieve isolation between the primary AC input and the secondary power supply. The primary winding of the transformer is isolated with insulating tape, and the primary and secondary sides of the skeleton are isolated. The AC passes through the human body and forms a loop with the earth. Danger of electric conduction to the human body. There are high-voltage tests for transformers, generally requiring 3KV.
The current relationship between the primary coil and the secondary coil:
When the transformer is running with a load, the change in the secondary coil current will cause a corresponding industrial iot gateway change in the primary coil current. According to the principle of magnetic potential balance, the current of the primary and secondary coils is inversely proportional to the number of coil turns, the side with more turns has a smaller current, and the side with fewer turns has a larger current.