Will 50Hz light flicker laws be reduced so as to make the world "greener"?

With Greta Thunberg getting stronger politically, do you believe there will be a relaxation on 100Hz/120Hz light flicker laws? (sorry i put "50Hz" in the title)

For example, the most efficient way to power LEDs (at 200W) off the EU/UK mains, is with a BCM Boost PFC feeding a long series LED bank. However, like that, in order to get light flicker down to low enough levels, one needs at least 100uF of (450V+) capacitance across the LED bank. This is bound to be electrolytic capacitance, since at 100uF, films are just too expensive.

Electrolytics have life time issues, and so this is not a “green” solution, unless of course the light flicker laws can be softened, and then just a small film capacitor can suffice instead of the large electrolytic bank.

At 200W, off the mains, one can of course achieve low light flicker and use low amounts of capacitance…however, this needs two power stages….a PFC stage, followed by eg a Buck LED driver stage……..the Buck LED driver stage can then reject the high output ripple of the “lowly output capacitanced” PFC stage…however, two power stages in cascade means less efficiency…..so again Greta Thunberg “laws” are violated. So will Light flicker level regulations be softened? (ie EN12464)

True, our scientific mind watches civil rulers politicizing everything more and more, making it tougher to create technology which has all these noble aims combined:
efficiency, affordability, reliability.
The 'green' laws may have fine print (today or tomorrow) allowing the possibility for some far (east) corner of the world to market an led driver which 'appears' to flicker less, and may even be cheaper. Experience shows that customers go for the cheaper deal regardless of reliability and lifetime. A particular standard may be relaxed so it no longer stands in the way. Sweetheart deals abound.

Poor Geta, getting blamed for street lighting now.....

If you allow flicker, you get strobing effects. Strobing is not only visually annoying, it gives the impression that some moving objects are stationary. That isn't a good idea in a situation where so many moving objects are involved. It would also stop much of the CCTV equipment looking at traffic and people movement from working.

If it really does become a problem, some kind of phased flickering would be a better solution, one where the LEDs are split into different groups within the same luminaire but brighten and dim at different times. This would make it similar to factory lighting where fluorescent fittings are wired on different phases of a three phase system to avoid strobing effects.

Brian.

It would also stop much of the CCTV equipment looking at traffic and people movement from working.

Click to expand...

Thanks yes, though as you know, there are now Cameras which can see perfectly clearly during high degrees of 100Hz flicker, by processing it out.

When I worked for a company which among other things manufactured magnetic ballasts (meaning that the arc current would be pulsing at powerline frequencies), a good trick was to use a capacitor in series with one of the lamps, to create a quadrature phase shift for one of the lamp's currents.

The reduction in flicker was impressive. Flicker is one of those things one can't see, but one will perceive. Subtle difference.

Another trick, used by the lamp manufacturers, was to use high persistence phosphors.

Poor Greta. I agree with Brian, this has nothing to do with her.

Perhaps it would be worthwhile experimenting with high frequency pulsing of LEDs. I'm thinking that if say three or four groups were sequenced, either singly or with overlap, it might be a way of avoiding strobe effects and at the same time reducing large current bursts so EMC is less of a problem.

That doesn't get around the fundamental problem of starting off with a stable DC supply and hence the requirement for a big capacitor though.

Brian.