Priežastys elektromagnetinis suderinamumas sunaudotas iki perjungimas maitinimas tiekimas
Priežastis priežastis elektromagnetinis suderinamumas problema sukelta 24V perjungimas galia tiekimas veikimas įėjimas perjungimas būsena aukšta įtampa ir didelė srovė yra gana kompleksas. Nuo perspektyva elektromagnetinis suderinamumas visa mašina, ten yra daugiausia bendra varža sukabinimas, linija į liniją sukabinimas, elektrinis laukas jungtis, magnetinis laukas jungtis jungtis ir elektromagnetinė banga jungtis. Trys elementai iš elektromagnetinis suderinamumas are: įbrėžimas šaltinis, Patogenas perdavimas ir sutrikdytas kūnas. Bendras varža sukabinimas daugiausia nurodo į į the common impedance between the disturbance source and the disturbed object electric, through which the disturbance signal enters the disturbed object. Line to line coupling most refers to the mutual coupling between wires that generate scratch voltage and įbrėžimas srovė duetas lygiagretus laidai.
Elektrinis laukas sukabinimas is daugiausia dėl į buvimą potencialą skirtumus, rezultatas in the mova of indukuotas elektriniai laukai to the disturbed body. Magnetinis laukas sukabinimas daugiausia nurodo į the mova of low-frequency magnetic fields generated near high current pulse power lines to the disturbance object. Elektromagnetinis laukas sukabinimas is daugiausia sukeltas pagal aukštą dažnį elektromagnetines bangas generuotas pagal pulsuojantį įtampą arba srovę, kuris spinduliuoja į išorę per erdvę ir porą atitinkantį sutrikdytą kūną. In fact, kiekvienas mova metodas negali būti griežtai atskirti, tik su su skirtingais fokusais.
In a 24V switching power supply, the main power switch opers in a high-frequency switching mode at a high voltage. The switching voltage and current are close to square waves. From spectrum analysis, it is known that the square wave signal contains rich high-order harmonics, which can reach a frequency spectrum of over 1000 times the square wave frequency. At the same time, nes the Leakage inductance and distributiond talp of the power transformer, as well as the working state of the main power switching device, are not ideal, when the high frequency is turned on or off, high frequency and high voltage peak harmonic oscillation is often generated. Aukštos eilės harmonikos generuojama pagal the harmoninis virpesiai are perduodami į the internal circuit per the distributed talpą tarp the switch tube and the radiator or radiated into the space through the radiator and the transformer.
Used for rectification and continuous current diodes, it is also an important reason for generating high-frequency disturbances. Because the rectifier and Flyback diode work in the high-frequency switching state, and because of the existence of the parasitic inductance of the diode's lead, the junction capacitance, and the influence of the reverse recovery current, they work at a very high voltage and current change rate, and produce high-frequency oscillation. Since the rectifier and Flyback diode are common close to the power output line, the high-frequency interference generated by them is most likely to be transmitted through the DC output line.
In order to improve the power factor of 24V switching power power supplies, active power factor correction circuits are adopted. At the same time, in order to improve the efficiency and reliability of the circuit and reduce the electric stress of power devices, a large number of soft switching technologies have been adopted. Among them, zero current, color current, zero current switching technology is the most wide used. Ši technologija labai redukuoja the electromagnetic interference generated by switching devices. Tačiau, soft switching lossless absorption circuits most utilize L and C for energy transfer, utilizing the unidirectional conductivity of diodes to achieve unidirectional energy conversion. Todėl, the diodes in this rezonansinė grandinė become a major source of electromagnetic disturbance.
In 24V switching power supplies, energy storage inductors and capacitors are generally used to form L and C filtering circuits to filter differential and common mode disturbance signals, and to convert AC square wave signals into smooth DC signals. Due to the distributed capacitance of the inductance coil, the inductance coil
