Industry power supply 48V manufacturers tell you that with the soaring living standards, various industries have also developed rapidly, and enterprise products have also begun to be improved in accordance with the needs of market development, so that their functions can be more excellent and meet the use standards of the public. The same is true for the power supply. Industry power supply 48V manufacturers tell you that switching power supplies are common necessities in daily life and can be used in many fields. Therefore, various performances of switching power supplies have also received extensive attention. This article will focus on the electromagnetic compatibility planning of switching power supplies. Analyze in detail, and propose a detailed plan to suppress electromagnetic interference, so that the switching power supply can obtain better performance to serve the public.

Industry power supply 48V manufacturers tell you that the most important thing about switching power supply is electromagnetic compatibility. Electromagnetic compatibility means that in a limited space, practice and spectrum range, all kinds of electrical equipment coexist without causing functional degradation. It includes electromagnetic interference and electromagnetic sensitivity. The most important content of the two aspects is electromagnetic interference, and a device with outstanding electromagnetic compatibility should be neither affected by the surrounding magnetic field nor cause electromagnetic interference to the surroundings.
Electromagnetic interference source in switching power supply:
1. Electromagnetic interference formed by switching circuit
Industry power supply 48V manufacturers tell you that the circuit is the most basic element to keep the switching power supply running, so in terms of switching power supply, the electromagnetic interference formed by the switching circuit is the interference source in the switching power supply, and its impact on the switching power supply is also the biggest. Will cause severe damage to the switching power supply. As the center of the switching power supply, the switching circuit has the main components of the switching tube and the high-frequency transformer. The quality of these two primary components will also have a great influence on the switching circuit. Therefore, in the switching circuit, the switching tube and the high-frequency transformer The quality of the product is also extremely important.
Industry power supply 48V manufacturers tell you that the switching circuit is an important part of the switching power supply, and its various interferences to the switching power supply are also multifaceted, and the causes are also diverse, so the cause and demand are analyzed from different aspects. In this article, we will analyze in detail from the following aspects:
(1) Switch tube load. Industry power supply 48V manufacturers tell you that the widespread application of switching tube loads in our country is the use of high-frequency transformer primary coils, which belong to the field of rational load, and the first moment the switching tube is operating, a great inrush current will occur in the primary coil. In addition, at the moment when the switch tube is disconnected, due to the characteristics of the primary coil, a part of the energy cannot be transferred from the first coil to the second coil, causing energy loss , Resulting in power interruption. The interruption of the power supply voltage will cause the magnetization impulse current to occur. At the same time, this noise will be conducted to the input and output terminals, causing conduction interference, and even severely, it may break down the switching tube and directly cause the switching power supply to collapse.
(2) Industry power supply 48V manufacturers tell you that the high-frequency switching current loop formed by the primary coil switch tube of the pulse transformer and the filter capacitor may have extremely large space radiation, which constitutes radiation interference, which is also due to the high-frequency impedance on the capacitor. The high-frequency circuit is conducted to the AC power source in a differential mode, which constitutes conducted interference.
2 Electromagnetic interference caused by diode rectifier circuit:
Industry power supply 48V manufacturers tell you that the reverse recovery current generated by the rectifier diode in the main circuit is different from the reverse recovery current of the freewheeling diode. Generally speaking, the reverse recovery current generated by the rectifier diode in the main circuit is relatively small. This will actually increase the electromagnetic interference of the switching power supply. Industry power supply 48V manufacturer tells you that because according to the relevant investigation results, the reverse recovery current generated by the rectifier diode in the main circuit has a relatively small value, resulting in a larger interference intensity and a wider frequency band. The rectifier diode in the main circuit Compared with other components, the voltage jump that occurs has a smaller value. This also causes the electromagnetic interference of the diode rectifier circuit to be more severe and affects the normal operation of the switching power supply.
Restraint of power interference:
Industry power supply 48V manufacturers tell you to suppress the electromagnetic interference of the switching power supply, firstly adopt the following two methods: one is to reduce the interference intensity of the interference source, and the other is to change the signal grounding method. In order to achieve these two results, we also need to improve the components and current channels of the switching power supply, and improve these aspects to suppress electromagnetic interference.
1. Reduce the interference of the switching power supply itself
After detailed analysis, we can know that reducing the interference of the switching power supply itself is the fundamental way to suppress the interference of the switching power supply, because if the interference of the switching power supply itself is not reduced, then even if the cause of electromagnetic interference from the outside has been effectively eliminated, the switching power supply The electromagnetic interference cannot be effectively suppressed. This is useless work, which not only wastes the time and energy of the operators, but also consumes a lot of money, but the results are not significant. Through the above analysis, it can be known that reducing the interference of the switching power supply itself is a useful method to make the electromagnetic interference of the switching power supply lower than the regulatory limit value and improve the function of the switching power supply.
Reducing the electromagnetic interference of the switching power supply itself is mainly carried out through the following aspects:
1. Reduce the interference that occurs when the power tube is turned on and off. Industry power supply 48V manufacturers tell you that we can know after the above description, because the voltage jump and the rectified current value of the rectifier diode in the main circuit are small, which will cause the electromagnetic interference of the switching power supply itself to a certain extent, so We need to reduce the interference in the process of turning on and turning off the power tube. However, there is no effective means to reduce the AC power of the switching power supply, so people now use the soft switching power supply technology, combined with reasonable component placement and reasonable printed circuit boards to improve the electromagnetic interference of the switching power supply. level.
2. Switch frequency modulation skills. Industry power supply 48V manufacturer tells you that according to the investigation results, the interference mode of modulated pulse with fixed frequency in the low frequency band is mainly manifested as the harmonic interference of the modulation frequency, that is, the electromagnetic interference of the low frequency band is mainly concentrated in the harmonics. In point, if the frequency is fixed in this way, it will cause severe interference to the switching power supply when the frequency reaches the low frequency band. Therefore, relevant technology operators can combine relevant skills and processes to fix the frequency according to their operating characteristics. The unchanging modulation pulse is changed to frequency conversion modulation. The industry power supply 48V manufacturer tells you that in this way, the switching power supply can effectively avoid the low frequency band and reduce the electromagnetic interference of the switching power supply itself.