Help: Power Factor Correction Design

[glenjoy]

I want to design a power factor corrector for households, are there any IC's that supports correction for 220V of supply?

Btw this is not an ordinary power factor correction for switching power supply.

 

[IanP]

Look Glenjoy,
There is no single IC that can provide a panacea to correct the power factor for domestic appliances ..
Too many variables ..

 

[prinsloo]

Why do you want to correct power factor of such a small place? You won't gain much in dollar/euro value for such a device. (by the way,a town of 25 Mw has a avarage power factor of 0.8-0.85) A HOUSE ONLY USE max 13Kw

 

[flatulent]

This will do you no economic good. The meter measures real power. All you will accomplish is reducing some of the power lost in the electrical transmission system prior to your meter. You could put a properly rated capacitor across your line but this would cost more energy in its construction than you would save society in the distribution line loss.

 

[glenjoy]

Hi,

Thanks for the advise my friends, now I changed my mind, as I am still curious abou the design, can somebody help me on how to actualy measure the power factor? I just want to build now a power factor meter.

First I want to know the phase difference between the voltage and current as I know this is the means of computing the power factor, if someone knows a better way or a circuit, kindly please share.

Thanks.

Glenjoy

 

[JuergFrefel]

Measuring the power factor is not quite as easy as it looks. It consist of two part:
Cos Phi (phase shift between current and voltage)
and the THD (total harmonic distortion, e.g. how much the current waveform differs from a perfect sine wave)

Unitrode (now part of Texas Instruments) makes a whole line of parts for active power factor correction. Check out the datasheet for the part UC3854 and the application note U-134. The explain very well how it works and give some insights into power factor correction.

-Juerg