Phase angle /P.F circuit

[gopi_sonsivri]

Hi all,

I am designing a energy meter using PIC controller.

I first actually want to measure the phase difference(ANGLE) between voltage and current.and i wud getpower factor by sending it to adc-->PIC the doing cos(phi) in controller program for the phi being read


here is a circuit i have drawn ...is there any prob or simple way to do it

Thank u in advance

[oldvan]

http://www.sonsivri.com/forum/index.php?topic=14054.0

might provide useful insights, especially the schematic:

[DTiziano]

Hi
To calculate the energy you need of course also the voltage and the current values.
So why do not you compute the active energy (Wh) directly from the samples values of current and voltage ?
If you sample the voltage and current some tenth time every period you can calculate the energy by integrating the V*I*dt without to detect the phase angle .

You can find additional details here:

http://instruct1.cit.cornell.edu/courses/ee476/FinalProjects/s2008/cj72_xg37/cj72_xg37/index.html

[gopi_sonsivri]

thanks but i am using different method...i use two small t/f and rectify by precision rectfier...diodes cause drop in that circuit if used directly n i need of high rating...