Buffer the input in a battery then use dc out from the battery to power your lights, no flickering. No need to reconfigure the entire grid and every device on it for niche applications.
Rectifying the AC, even with a full bridge rectifier, will still drop to zero every time the AC voltage crosses the zero line. So usually a capacitor is added to buffer this output. Its capacity depends on the size of the load.
Good LED bulbs have a smoothing capacitor after the full bridge rectifier. This allows the LED to maintain most of its output during the low points in the cycle, resulting in minimal to no flicker when recording.
High frequency is generally bad for transmission line losses, so getting power from A to B is better at lower frequency --- DC is a great option here.
If we switched to DC, many things would still flicker though as they would presumably use switching power supplies, but those could be relatively high frequency like you said.
Interestingly, airplanes use 400Hz, as transmission over distance doesn't matter, and transformers can be made much smaller/lighter.
As far as I understand, a DCDC converter is less efficient and more expensive than an equivalent ACAC converter. I don't know about switching power supplies, and whether that's true or extendable to the transformer case, sorry.
Long distance point to point power transmission (like internationally) is often DC because transmission losses become more important.
I don't think that's actually true. To do AC to AC conversion at grid frequencies normally requires large inefficient transformers. A PC power supply is an example of a switch mode power supply. Basically what happens is: AC mains -> DC (at mains voltage) -> AC (high frequency, mains voltage) -> transformer -> AC (low voltage, still high frequency) -> DC (low voltage). Why do all this? Because doing the voltage conversion at grid frequency would need a much bigger transformer. They could just do the voltage conversion at grid frequency and only have to rectify once with no conversion back to ac, but it's actually less efficient and requires more expensive hardware. So actually DC to DC conversion is more efficient, even if it means using high frequency AC in the middle. Not all switch mode supplies use this AC trick, though they do all involve switching current. buck and boost converters are used in smartphones, laptops, motherboards don't have any transformer and are incredibly compact and efficient.The fact that many many things also need DC would be a bonus. Recitifying single phase AC at low frequency is not the most efficient thing in the world. Three phase is better, but having straight DC and only needing to change voltage would probably be best.
They’re more efficient than old school ac-dc linear supplies (of which an ac transformer is just a part of). However if you just want to step up or down ac voltage, transformers are quite efficient.
But we could just attach an antenna to our roofs and steal electricity, I consider it worth the transmission loss if we can create more transmission loss.
Even a switch mode power supply doesn't really flicker since they have a rectification and smoothing stage on the output to produce a DC voltage. The switching is done on the input to set the duty cycle which controls the voltage/current ratio at the output.
If lights are flickering when you record videos, you probably need to change the settings on your camera to match your country’s grid frequency. Almost every video recording device will have a 50/60Hz setting somewhere.
For incandescent bulbs the power drop around the zero voltage cross doesn't last long enough to extinguish the filament, since it's basically just glowing from being heated. The only lights which actually do "flicker" under nominal conditions are old ballast driven florescent lights. Most modern LEDs rectify the AC and modern CFLs boost the line frequency to like 20kHz to prevent the arc from getting extinguished.
A lot of christmas lights still flicker. Not sure how they're wired, but I think they just feed AC to the diode, so it's off for the negative half of the wave
Incandescent bulbs like that in the picture don't really flicker. They might pulsate a little bit but even at their faintest they would still have significant light output.
Some LED bulbs do flicker though, it depends on how they implement the AC to DC conversion. If they flicker, it is easily noticeable to the human eye, especially when looking at motion.
32 Comments
kbobabob@lemmy.dbzer0.com · 21 pts · 185d
Turn the lights off when you go to bed.
Xerxos@lemmy.ml · 1 pts · 184d
Are they from Toshi Station?
LodeMike@lemmy.today · -6 pts · 185d
No it's not lol they still flicker out eyes just dont pick it up
Hope@lemmy.world · 104 pts · 185d
It has a 60Hz electric waveform in, and it produces visible light, which is in part a ~500THz wave.
sik0fewl@piefed.ca · 3 pts · 185d
Do you think we will ever change our power grid to have a higher frequency so that our bulbs don’t flicker when we record things?
flyingSock@feddit.org · 23 pts · 185d
Buffer the input in a battery then use dc out from the battery to power your lights, no flickering. No need to reconfigure the entire grid and every device on it for niche applications.
iSeth@lemmy.ml · 5 pts · 185d
Just rectify the AC, if the voltage isn't too much.
You don't need a buffer unless the power fluctuates.
Not a licensed electrician
hereiamagain@sh.itjust.works · 6 pts · 184d
Rectifying the AC, even with a full bridge rectifier, will still drop to zero every time the AC voltage crosses the zero line. So usually a capacitor is added to buffer this output. Its capacity depends on the size of the load.
iSeth@lemmy.ml · 1 pts · 184d
Good point. Pulsed isn't for everything
ViatorOmnium@piefed.social · -1 pts · 185d
Assassassin@lemmy.dbzer0.com · 18 pts · 185d
Good LED bulbs have a smoothing capacitor after the full bridge rectifier. This allows the LED to maintain most of its output during the low points in the cycle, resulting in minimal to no flicker when recording.
MOCVD@mander.xyz · 13 pts · 184d
Alright, show me your eyebrows
Assassassin@lemmy.dbzer0.com · 8 pts · 184d
Peh chu chu peh chu chu peh monobrow wiggle
Cort@lemmy.world · 6 pts · 184d
Implying there's more than one
hereiamagain@sh.itjust.works · 5 pts · 184d
I loled
SkunkWorkz@lemmy.world · 4 pts · 184d
He electrocuted himself
qjkxbmwvz@startrek.website · 15 pts · 185d
High frequency is generally bad for transmission line losses, so getting power from A to B is better at lower frequency --- DC is a great option here.
If we switched to DC, many things would still flicker though as they would presumably use switching power supplies, but those could be relatively high frequency like you said.
Interestingly, airplanes use 400Hz, as transmission over distance doesn't matter, and transformers can be made much smaller/lighter.
FishFace@piefed.social · 8 pts · 185d
Also if we switched to DC, you'd need costly dcdc transformers to step up the voltage for transmission and back down again for domestic usage
NotANumber@lemmy.dbzer0.com · 2 pts · 185d
Aren't switching mode power supplies smaller and more efficient than regular AC transformers anyway?
FishFace@piefed.social · 5 pts · 185d
As far as I understand, a DCDC converter is less efficient and more expensive than an equivalent ACAC converter. I don't know about switching power supplies, and whether that's true or extendable to the transformer case, sorry.
Long distance point to point power transmission (like internationally) is often DC because transmission losses become more important.
NotANumber@lemmy.dbzer0.com · 1 pts · 184d
I don't think that's actually true. To do AC to AC conversion at grid frequencies normally requires large inefficient transformers. A PC power supply is an example of a switch mode power supply. Basically what happens is: AC mains -> DC (at mains voltage) -> AC (high frequency, mains voltage) -> transformer -> AC (low voltage, still high frequency) -> DC (low voltage). Why do all this? Because doing the voltage conversion at grid frequency would need a much bigger transformer. They could just do the voltage conversion at grid frequency and only have to rectify once with no conversion back to ac, but it's actually less efficient and requires more expensive hardware. So actually DC to DC conversion is more efficient, even if it means using high frequency AC in the middle. Not all switch mode supplies use this AC trick, though they do all involve switching current. buck and boost converters are used in smartphones, laptops, motherboards don't have any transformer and are incredibly compact and efficient.The fact that many many things also need DC would be a bonus. Recitifying single phase AC at low frequency is not the most efficient thing in the world. Three phase is better, but having straight DC and only needing to change voltage would probably be best.
adb@lemmy.ml · 2 pts · 185d
They’re more efficient than old school ac-dc linear supplies (of which an ac transformer is just a part of). However if you just want to step up or down ac voltage, transformers are quite efficient.
NotANumber@lemmy.dbzer0.com · 1 pts · 185d
stupidcasey@lemmy.world · 6 pts · 185d
But we could just attach an antenna to our roofs and steal electricity, I consider it worth the transmission loss if we can create more transmission loss.
socsa@piefed.social · 3 pts · 185d
Even a switch mode power supply doesn't really flicker since they have a rectification and smoothing stage on the output to produce a DC voltage. The switching is done on the input to set the duty cycle which controls the voltage/current ratio at the output.
Thunderbird4@lemmy.world · 5 pts · 185d
If lights are flickering when you record videos, you probably need to change the settings on your camera to match your country’s grid frequency. Almost every video recording device will have a 50/60Hz setting somewhere.
Tehdastehdas@piefed.social · 5 pts · 185d
How about banning flickering lamps? I'd ban screeching power adapters too.
socsa@piefed.social · 30 pts · 185d
For incandescent bulbs the power drop around the zero voltage cross doesn't last long enough to extinguish the filament, since it's basically just glowing from being heated. The only lights which actually do "flicker" under nominal conditions are old ballast driven florescent lights. Most modern LEDs rectify the AC and modern CFLs boost the line frequency to like 20kHz to prevent the arc from getting extinguished.
deltapi@lemmy.world · 3 pts · 184d
Modern CFLs use an arc? I thought they were cathode based, emitting UV from forcing mercury vapour to dance
Hadriscus@jlai.lu · 2 pts · 184d
mercury vapour dances ?!
Sasquatch@lemmy.ml · 1 pts · 183d
A lot of christmas lights still flicker. Not sure how they're wired, but I think they just feed AC to the diode, so it's off for the negative half of the wave
NeatNit@discuss.tchncs.de · 30 pts · 185d
Incandescent bulbs like that in the picture don't really flicker. They might pulsate a little bit but even at their faintest they would still have significant light output.
Some LED bulbs do flicker though, it depends on how they implement the AC to DC conversion. If they flicker, it is easily noticeable to the human eye, especially when looking at motion.
angband@lemmy.world · 2 pts · 185d
Flickering lights used to mean a temporary < 1s power outage.