The bifilar pancake coil at its resonant frequency

[gyulasun]

Note that I said 400 volts peak-to-peak so I get the 0.98 microjoules from 200 volts.

I am surprised by your answer.   Please explain what conversion did you make to get 200 V from 400 V?
I knew you must have entered 200 V into the formula to get 0.98 microjoule
energy in a 49 pF capacitor but now there is another problem...

The moment the voltage level is just say 400 V across a capacitor (i.e. you can measure it in that moment),
then you have to use 400 V in the formula to get the stored energy in that moment.
Such moments always occur in resonant LC circuits whenever all the coil energy has just 'gone' into the
capacitor and the coil has no any magnetic energy left in it.  And the received energy in the capacitor manifests
as a peak to peak voltage across it but you need not convert this to any other voltage value at all, okay?

Gyula

[Grumage]

Dang, lets all just get together and have a bifi coil show!    Nice


Mags

Thanks Mags.

That BiFi coil is damaged, overstressed, broke the insulation down.

I would suggest a good coat of Shellac be applied if you're going to use one on an Induction hob.... 

Cheers Graham.

[MileHigh]

My point is unlike you, I have a solution.....smartass...

I have a solution.

So what's your solution?  If you refuse to answer, then what's the point?

[MileHigh]

I am surprised by your answer.   Please explain what conversion did you make to get 200 V from 400 V?
I knew you must have entered 200 V into the formula to get 0.98 microjoule
energy in a 49 pF capacitor but now there is another problem...

The moment the voltage level is just say 400 V across a capacitor (i.e. you can measure it in that moment),
then you have to use 400 V in the formula to get the stored energy in that moment.
Such moments always occur in resonant LC circuits whenever all the coil energy has just 'gone' into the
capacitor and the coil has no any magnetic energy left in it.  And the received energy in the capacitor manifests
as a peak to peak voltage across it but you need not convert this to any other voltage value at all, okay?

Gyula

The model is a self-resonating bifilar coil with a ground reference on one terminal and the other terminal swinging back and forth between +200 and -200 volts.

[MileHigh]

Also could you measure the capacitance between the windings? Separated of course not in series connection. Just interested to see what you get.with that wire with more close proximity surface area.  Its gota be more than conrad had with the insulation and round wire. Not putting his effort down, just to see if you get better capacitance with what you got.

Note that Conrad calculated the capacitance based on the self-resonant frequency and I don't think he made a measurement with the separated windings.  My gut feeling is that the capacitance measured between the separated windings will be in the same ballpark as the calculated capacitance from the self-resonant frequency but I am really not sure.