T
treez
Guest
Hello,
At one company where I worked, they had done a 100W Offline flyback SMPS (120VAC input), and had used four large diff mode inductors in the AC input filter that were rated for 6Arms of current.
(it was actually a Dual isolated PFC'd flybacks for 100W total)
Their is a total of 236nF of ceramic capacitance downstream of the rectifier bridge on the HVDC bus.
Their input filter schem is as attached.
Why had they used such high current inductors? There was a suggestion that it was because they would not saturate under transients. This was an aerospace application. The power supply would be used on civil passenger aircraft to provide a voltage bus for led lighting.
Why use such overly high current rated inductors?
This is the inductor datasheet…..
74437429203151 inductor
https://katalog.we-online.de/pbs/datasheet/74437429203151.pdf
- - - Updated - - -
By the way, the SMA TVS that you see on the schem is the only transient protection component on the entire schematic.
At one company where I worked, they had done a 100W Offline flyback SMPS (120VAC input), and had used four large diff mode inductors in the AC input filter that were rated for 6Arms of current.
(it was actually a Dual isolated PFC'd flybacks for 100W total)
Their is a total of 236nF of ceramic capacitance downstream of the rectifier bridge on the HVDC bus.
Their input filter schem is as attached.
Why had they used such high current inductors? There was a suggestion that it was because they would not saturate under transients. This was an aerospace application. The power supply would be used on civil passenger aircraft to provide a voltage bus for led lighting.
Why use such overly high current rated inductors?
This is the inductor datasheet…..
74437429203151 inductor
https://katalog.we-online.de/pbs/datasheet/74437429203151.pdf
- - - Updated - - -
By the way, the SMA TVS that you see on the schem is the only transient protection component on the entire schematic.