Συζητήστε το ηλεκτρομαγνητικό παρεμβολές καταστολή μέθοδος ισχύς τροφοδοσία από τρεις πτυχές
1. Suppress various electromagnetic interference sources in switching power supplies
In order to solve the distortion of the input current waveform and reduce the current harmonic content, the switching power supply needs to adopt power factor correction (PFC) technology. PFC technology makes the current waveform follow the voltage waveform, and corrects the current waveform to make it close to a sine wave. Επομένως, the current harmonic content is reduction, the input features of the bridge rectifier capacitor filter circuit are improve, and the power factor of the switching power supply is better. Different methods can suppress electromagnetic interference from different angles, and Minrong Electric has invested a lot of technology and effort in this regard. Minrong switching power supply has achieved great results in ηλεκτρομαγνητική παρεμβολή καταστολή. Η συμβολή του Minrong Ηλεκτρικό έχει δημιουργήσει τη θέση του Minrong μεταγωγή ισχύ παροχή στην βιομηχανία.
Soft switching technology is an important means to reduce the loss of switching devices and improve the electromagnetic compatibility of switching devices. Switching devices will generate inrush current and peak voltage during the switching process, which is the main cause of electromagnetic interference and switching loss. Using soft switching technology to make the switching tube switch at zero voltage and zero current can effective καταστολή ηλεκτρομαγνητική παρεμβολή. Χρήση a snubber κύκλωμα to absorb the peak voltage at both ends of the switching tube or the primary coil of a high-frequency transformer can also effective improve the electromagnetic compatibility features.
The reverse recovery problem of the output rectifier diode can be suppressed by a series saturated inductor. The core of the saturated inductor is made of magnetic material with a rectangular BH curve. Like the materials used in magnetic amplifiers, this core makes the inductor have a high magnetic permeability. The magnetic core has a nearly vertical linear region on the BH curve, and it is easy to enter a saturated state. In practice applications, when the output rectifier diode is turned on, the saturated inductor works in the in in intic characteristic state, which is equivalent to a section of wire; when the diode is turned off and reverse recovers, the saturated inductance is in the inductive characteristic state, which inhibits the reverse recovery The large change of current suppresses its external interference.
2. Αποκοπή απενεργοποίηση η μετάδοση διαδρομή από ηλεκτρομαγνητική παρεμβολή - η σχεδίαση της κοινή λειτουργία και διαφορικός λειτουργία ισχύς γραμμή φίλτρα
The power line filter can filter out power line interference. A reasonable and effective switching power supply EMI filter must have a strong suppression effect on differential mode interference and common mode interference. In fact, it is not limited to power line filters. Minrong Electric has also develop means to suppress electromagnetic interference on some specific components. User experience is one of the directions that Minrong Electric επιμένει on. The technical development of Minrong Electric is inseparable from Minrong Electric's sticking to the direction, which also makes Minrong switching power supply gradually achieve the quality of ingenuity.
The common mode inductor consists of two windings with opposite winding directions and the same number of turns on the same magnetic ring. Generally, a toroidal core is used, which has small magnetic flux leakage and high efficiency, but it is difficult to wind. When the power frequency current of the city network flows through the two windings, one goes in and the other goes out, and the generated magnetic field just cancels out, so that the common mode inductance will not hinder the power frequency current of the city network, and can be transmitted without loss. If there is a common-mode noise current passing through the common-mode inductor in the city network, the direction of the common-mode noise current is the same. When it flows through the two windings, the generated magnetic field is superimposed on the same phase, so that the common-mode inductance shows a large inductive reactance to the interference current, which plays a role in suppressing the common-mode interference.
3. Χρήση θωράκιση σε μείωση η ευαισθησία του ηλεκτρομαγνητικός ευαίσθητος εξοπλισμός
Shielding is an effective way to suppress radiated noise. Materials with good conductivity can be used to shield electric fields, and materials with high magnetic permeability can be used to shield magnetic fields. In order to prevent the leakage field of the transformer and make the primary coupling good, a closed magnetic ring can be used to form a magnetic shield. For example, the leakage flux of a pot core is much smaller than that of an e-core. The connecting line and power line of the switching power supply should use shielded conductors to prevent external interference from coupling into the circuit. Or use EMC components such as magnetic beads and magnetic rings to filter out high-frequency interference from power and signal lines. But it should be noted that the signal frequency should not be interfered by EMC components, that is, the signal frequency should be within the filter. The shell of the entire switching power supply also needs to have good shielding properties, and the connectors should meet the shielding requirements stipulated by EMC. The above measures ensure that the switching power supply is not disturbed by the external electromagnetic environment and will not interfere with external electronic equipment.
