The composition principle of switching power supply
1. The main circuit The whole process of input from the AC power grid and output by DC includes:
1. Input filter: Its function is to filter the clutter existing in the power grid, and at the same time prevent the clutter generated by the machine from feeding back to the public power grid.
2. Rectification and filtering: directly rectify the AC power of the grid into a smoother DC for the next stage of transformation.
3. Inversion: Convert the rectified direct current into high-frequency alternating current, which is the core part of the high-frequency switching power supply. The higher the frequency, the smaller the ratio of volume, weight and output power.
4. Output rectification and filtering: According to load requirements, provide stable and reliable DC power supply.
2. On the one hand, the control circuit samples from the output terminal, compares it with the set standard, and then controls the inverter to change its frequency or pulse width to achieve stable output. On the other hand, according to the information provided by the test circuit, the protection Circuit identification, provide control circuit to carry out various protection measures for the whole machine.
3. Detection circuit In addition to providing various parameters in the protection circuit in operation, it also provides various display instrument information.
4. Auxiliary power supply It provides power supply for different requirements of all single circuits.
Power supply → input filter → full bridge rectification → DC filter → switching tube (oscillating inverter) → switching transformer → output rectification and filtering.
