At 02:07 PM 19/11/2012, you wrote:
>Current project is an AC volt/amp/power/power factor meter using an
>18F2620. It is a for-fun project.
>
>I digitize one complete cycle of the 60 Hz voltage and current waveforms
>using the ADC, saving 256 8-bit samples.
>I compute RMS voltage and current, and power factor by calculating the
>phase shift. Life is good.
>
>But just for fun, I want to be able to calculate the power factor for
>non-linear loads, such as a switching power supply.
> >From what I have read, I need to determine the harmonic content of the
>current waveform.

Hi, Larry:-

Power factor is just P/(Vrms*Arms).

If you are calculating average power P correctly (the integral
of v(t)*i(t) over a period) then I think you just need to do the
same for v(t)^2 and i(t)^2 and crunch those three numbers with
a multiply, sqrt and divide.

--sp

--=20
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