Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Any idea what the power factor of this current waveform is?

Status
Not open for further replies.
T

treez

Guest
Newbie level 1
..Hello,
..It is the mains current waveform into a simulation of a 10W flyback LED driver (mains voltage also shown)
Unfortunately, LTspice doesn't do power factor.
 

Attachments

  • pow fac.jpg
    pow fac.jpg
    83.8 KB · Views: 147

Unfortunately, LTspice doesn't do power factor.
You mean, it doesn't do it automatically. It's quite easy to get it calculated in LTspice or other SPICE variants, e.g. using .fourier analysis.
 

The attached mains voltage and current gives a power factor of 0.87

V(rms)= 233V, I(RMS) = 0.052A, Average of v.i product over one period = 10.58W

therefore, power factor = 10.58/12.116 = 0.87 ...?
...seems very good for such a 'skewy' looking waveform
 

Attachments

  • powfac1.pdf
    1.1 MB · Views: 138

I don't agree very much with your calculation.
I see (in your last pdf file) that also the voltage isn't (perfetct) sinusoidal, the lower part is increasing with time and doesn't follow the sinus shape. Furthermore a non-zero DC is superimposed.
 
  • Like
Reactions: treez

    T

    Points: 2
    Helpful Answer Positive Rating
the voltage was programmed to be sine, and looks sine.
I dont see the dc.
yes the current is non sine though.
 

The attached mains voltage and current...
The 1MB(!!!) PDF you attached contains this image:

What is the green trace supposed to be showing? It's certaily not mains voltage, and isn't even a very good representation of full-wave rectified mains voltage.

The amplitude and waveform of both the green and blue traces are constantly changing as well, so whatever they are, this isn't even a steady-state measurement.

Was there any purpose in uploading this other than to waste server space and waste our time and bandwidth when we download it? At least the (sensibly sized) image you showed in post 1 made sense.

I dont see the dc.
You're kidding, right? The green trace doesn't even cross zero - it's positive all the way.
 
  • Like
Reactions: treez

    T

    Points: 2
    Helpful Answer Positive Rating
right, I now see your point, I measured it in the wrong place..its actually zero dc level.
as you know pfc ccts have slow feedback loops and take ages to get into steady state
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top