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Offline Flyback LED driver input current is oscillating near zero cross

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Flyback

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Please confirm that the following mains input current waveform to a 17W Offline LED driver is not potentially damaging to the mains supply system, even if millions of these devices operate?

(Green = Mains input current;
Red = Mains input voltage;
Light Blue = HVDC post rectifier bus)

Our contractor says it could be damaging.
Mains input current average is 111mA, Mains input current RMS is 0.17A

LTspice of flyback attached, also schem
 

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  • Waveforms.jpg
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Your "zero cross" seems to be missing "zero". You can (do) propagate those signals back up the mains line. What's the definition of "damage the mains supply system"? Will it burn out the cables to your building? No. Will it cause noise/distortions in the neighbors AC line? Probably. Will it cause extra clock cycles in an old-time AC wall clock? Maybe.
 
Mains input current average is 111mA, Mains input current RMS is 0.17A
More importantly the oscillation bursts have peaks of ~0.8A.
 
L5,6; Are they coils or a common mode transformer? Normally I use a common mode transformer.
It looks like you are trying to filter differential noise and did nothing for common mode. Where are the Y-caps?
Have you looked to see if the noise is common or differential?
1595559600750.png

Just for fun try 220pf 1kv caps across D4,5,6,7. Interesting to know if better or worse.
It appears the PWM drops it frequency, very low, at zero crossing. This makes the filter less effective.
 
Thanks, the noise in the top post is diff mode. I havent shown the Y caps here, but have one across the transformer (flyback)
We will have a common mode choke on the real thing.
 
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