Re: 5MV, 312kW

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Bart Anderson <classi6-at-classictesla-dot-com> 

Hi Finn,

Tesla list wrote:

>Original poster: Finn Hammer <f-h-at-c.dk>
>Here's about what it would look like
>
>>(complete with 6 foot stick-man for comparison),
>>http://www.classictesla-dot-com/temp/5mv.gif
>>One other item would be the "small" 312.5KW at 50kV. Vp would be down 
>>around 39% putting Vtop at 2.8MV at 100 bps. Leaving the system as is, we 
>>could drop the breaks down around 41 bps or leave at 100 and up the power 
>>to say 750KW!
>
>
>I don`t see how Vp is dropping. I set it at 50kV because it is a nice 
>number, what`s causing the drop?
>
>Cheers, Finn Hammer

When looking at Vtop, I think it is appropriate to look at the voltage as a 
function of capacitance at the moment in the cycle when all the energy is 
stored in the capacitance of the resonator. I was also looking at peak 
volts for this value while running the coil. Anyway, that moment of peak 
voltage can be expressed as Vtop = eVp x sqrt(Cpri/Cee). eVp is the 
effective voltage at the break rate and charge rate on the cap, Cpri is 
obvious, and Cee is a lumped capacitance to represent the equivalent 
capacitance required to store all the energy in the resonator at the 
instant in the cycle when all the energy is momentarily stored in the 
capacitance. Cee is an output of Geotc (thus, Javatc has the ability to use 
it for Vtop).

eVp was causing the drop.

It had to with the charge rate of the cap at 100 bps. I didnt save the data 
when I worked this out. Just kind of worked it out and placed the numbers 
found in the reply. I just ran it again and realized the picture I showed 
before was short by 100 inches (secondary; I input 150 instead of 250). 
Thus, the toroid was adjusted to height. The numbers change somewhat (196pF 
on topload, Fres closer to your 25kHz: I showed 28kHz when all is said and 
done). The 312.5kW still show 2.8MV because cap volts (eVp) is down to 
27.8kV. This is due to a charge time constant of 0.5 on the 2.5uF cap when 
running at 100 bps, where the time reference is 10ms (50 Hz 1/2 cycle). The 
full charge time on the 2.5uF cap is 100ms with a 312.5kW supply at 50kV.

Take care,
Bart