Power Factor with LED vs. magnetic ballast lighting

[Fishn sparky]

Good afternoon Gents,

Question....

As we further progress down the road of LED lighting in both commercial and residential lighting, what happens to our power factor? Take a residential dwelling for example. Most lighting, go back 5 years, was/is incandescent. This would put the power factor pretty close to unity as current and voltage are in phase ( excluding motors of course). As we introduce LED retrofit lighting as well as installation of new construction LED systems, what happens to PF now? I would think that it lags now.

How about commercial installations? As we change out magnetic ballast with LED technology our PF becomes closer to unity (not including motors). Obviously, with the reduction of older magnetic ballast our PF gets better but how much better with LED? Do electronic ballast have the same effect as an LED driver in regards to PF?

Any ways, everyone's thoughts are welcome and look forward to your responses!!

 

[GoldDigger]

Uncompensated bridge rectifier input DC power supplies have a poor distortion power factor and may also have a trace of capacitive (leading) current.
These days most LED and CFL drivers are designed for a reasonably good PF. You need to look at individual device specs.

Sent from my XT1585 using Tapatalk

 

[steve66]

This looks like it explains it pretty well:

https://www.ecnmag.com/product-release/2011/08/power-factor-correction-techniques-led-lighting

One thing I might highlight:

The US Department of Energy (DOE) Energy Star program mandates minimum acceptable power factors or 0.7 and 0.9 respectively for domestic and commercial LED lights.

So most lights would have a minimum PF of 0.9 for commercial applications.

 

[Jraef]

Why worry about PF in a residential application anyway?

Regardless, most Switch Mode Power Supplies (SMPS), the basis of almost all things electronic now, are going to be PF compensated (controlled) resulting in that .9 PF as mentioned. You might often see it referred to as having "PFC" in the feature description list. That will be displacement PF of course, because magically, we tend to ignore distortion PF since most PF meters don't read it since it takes place at much higher harmonics. But that's another story.