In alt.engineering.electrical krw wrote: | In article , | alt.engineering.electrical, snipped-for-privacy@ipal.net says... |> In alt.engineering.electrical krw wrote: |> | In article , |> | alt.engineering.electrical, snipped-for-privacy@ipal.net says... |> |> In alt.engineering.electrical Victor Roberts wrote: |> |> | On 9 Jan 2008 05:52:14 GMT, snipped-for-privacy@ipal.net wrote: |> |> | |> |> |>In alt.engineering.electrical bud-- wrote: |> |> |>
|> |> |>| Does the spectrum cause migranies and "skin eruptions"? I thought |> |> |>| migraines were flicker rate which should be a non-issue with CFLs. |> |> |>
|> |> |>I see CFLs that flicker. Probably very cheap ones. But they exist. |> |> |>
|> |> |>BTW, I bought an LED flashlight the other day that has a white spectrum |> |> |>that does not bother me like other LEDs and all fluorescents and metal |> |> |>halides do. And it's a rather bright and well built one. LEDs are now |> |> |>looking more like they could be my future efficient lighting method. |> |> | |> |> | Line-powered LEDs can also flicker if the DC link is not |> |> | properly filtered. |> |> |> |> No doubt. Maybe one day the lighting industry will figure out how to |> |> properly smooth out the DC? Hint: it can be done without those big |> |> capacitors that power supplies of days gone by had. One idea that |> |> comes to mind is to chop the current with a pulse width varied to |> |> compensate for the lower frequency component(s) of the ripple. |> | |> | The same energy has to be stored. |> |> Stored? What do you mean stored? That's not the only way to do it. | | I see what VR is talking about but that's going to play hell with | the PF. The EU isn't going to like that much and I'd imagine the | US won't wait forever, particularly if every light bulb on the | planet plays these games. There are two zeros per cycle to "smooth | over".
The flicker will be worse in Europe.
So basically, it comes down to producing smooth DC while keeping PF near 1. And it would seem LEDs have the same issue.
Incandescent avoids the issue by having a long term temperature filament. That is, the filament remains hot even during zero crossing. So what about a phosphor that can continue to glow at the same color? FYI, I do see the existing phosphors glowing at zero crossing, but the color is different.
Or maybe we just need DC distributed in the home. But don't get any idea that Edison was right ... he was selling pulsing DC.