Re: AC to Cap Dump

Body

Hi Hob,

Looking at your formula again I think there is an error in the calculation of the power going into the battery. Power can't be correctly calculated using the average current. A better way to do it is by using the RMS current when doing the calculation. This requires knowing the shape of the curve describing the current as any change of the curve shape changes the RMS current.

Take a look at the attached document with some examples taken from this document 'Waveform RMS Equations' (direct link): http://www.convertertechnology.co.uk/index.php? s=file_download&id=57 http://www.convertertechnology.co.uk/index.php? s=file_download&id=57.
 The source document was found here: http://www.convertertechnology.co.uk/index.php?c=technical_useful&s=50Technical http://www.convertertechnology.co.uk/index.php?c=technical_useful&s=50Technical

Regards
Ole 

---In [email protected], <hob.nilre@...> wrote :

 Hi Ole,

Nice plot, thanks. I'm quite confident that my math is ok. If I compare it to mechanics Vbat*Q would correspond to F*x which is work done. Similarly, comparing the capacitor to a spring, although not as obvious, Q=C*V would correspond to x=F/k, or to make the mechanical side familiar, F=k*x corresponds to V=Q/C since C corresponds to 1/k, a hard spring corresponds to a small cap. So, all put together, I think my formulas adds up. I'm fully aware that lots of energy in the cap gets lost, but right now I'm only focusing on whats going into the battery, not how effective the whole circuit is and what the losses are. I just want to know if pulsing a battery is something to pursuit, and it seems it is. Next step is to make it efficient.

/Hob