Poor power factor when 150W LED driver dimmed down to 30W

[treez]

Our 150W offline 230VAC, buckboost, single stage PFC’d LED driver has poor power factor (0.85) when dimmed down to 30W. This is due to ringing of current in the input filter near the mains zero crossing. We could put a damped filter in so as to mitigate this, but do we need to bother?....i mean, the power factor is 0.98 when it runs at 150W power. So surely the regulatory standards people will only be interested in what the power factor is like at the maximum power, ie, 150W?

 

[Kajunbee]

The only information I could come across was for external power supply's. The coc tier 1 regulations were supposed to become mandatory January 2017. If so these type supply's would have a minimum efficiency at 10 % load that they would have to meet. Coc tier 2 next year would lower the bar again if made mandatory. Wish I had more but finding that kind of information is like pulling teeth.