hello
today i got the fod3184 to drive my igbts optoisolated to allow the positive charge left on the cell to return to the isolated ground capacitance... this capacitance is in parallel with a diode that allow the electrons to be discharged to ground earth but when positive charges come it will get charged using electrons from ground to counterbalance the positive charges left on the cell.. . the potential rise will only depend on the capacitance.. so is good idea to start with a considerable value to accomodate the charge without rising the voltage in a manner that will kill the optoisolation..
i would keep within 2kv 100nf limit to start testing and i´m thinking of adding a tvs in parallel to limit it to this voltage
is important to have the current wave form on the oscilloscope to get track of the amps peak...
also is good to have a voltage reading of the igbt voltage to be safe about whats going on
every component burn is a big step backwards specially having no money to get more... i guess this components are here since about 2 years now it was a time that i had some money spare and decided to get components for the future testing... if i didnt had this components here i would probably get a long time until testing...
now i need to buy some 14 AWG wire and some 18AWG for the coils and pulse transformer
as i´m planing to have 10amps discharge to start with my primary will need to handle 30 amps as the pulse transformer is 1:3 but the switch will be seeing 40 amps or little more as the secondary is in series with the primary
the charging choke work as a load during pulse on! helping concentrating the power for later use during the collapse
the lower is the voltage applied the lower can be the inductance of the charging choke for the same amps so the greater is the speed of the discharge
so decreasing the coil size or frequency increase power out
increasing voltage and or amps increase power output
but increasing the coil increase the time of discharge and reduce power
Today i also buy a diaphragm pump to use with my filter it claims to be 100psi 6.8 bar 3amps 12v i hope it works ok because i got the cheapest one i pay like 20$ on it
so i would really like if you by any chance want to collaborate with me because i´m buying all this stuff with credit card but i´m not at a good situation to spend on this components.... of course i´m trying to use all i have to avoid having to buy more stuff
hopefully i live in a big house and i accumulated all the prototypes and spare parts i bought long this 13years researching
so to donate please follow this link
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as a counterpart i can make some videos with the progress of the tests and explaining better what we are doing here.. thanks so much for your effort in changing the word!
If you enjoy this website you can also contribute with it and other members that are working hard at this technology all of them so far as i know by their own cost and time! Be aware of that! Even if you just read and not a scientist or not able to do experiments you can help who can and follow the progress and be part of something great!
In attachment i added a excel sheet showing my calculations
i will explain here
the idea is to use inductive discharge
when we charge an inductor we charge it with current
1 Henrie is equal to L = 1 Volt * 1 Second / 1 Amp
this mean that if you have 1 henrie inductor and you apply 1 volt for 1 second you will have 1 amp on it ... the current increase linearly if dc is applied
so you have also 0.5 Joule because energy E = 1 Amp ^ 2 * 1 Henrie / 2
so my calculation assume 50% pulse width and i manipulate the frequency and voltage and current desired to get the inductor value i need to match that condition
i made it this way because it change the parameters dynamically allowing me to discover the behavior of parameters
when this energy is discharged it is discharged into the cell in 100 nanoseconds scale and will depend on the cell capacitance and choke inductance
so from the energy i got the maximum voltage for resonant discharge
and also calculated the voltage and time for discharge considering water just a resistance
this is simply taking the amps and multiply by the resistance V=I*R and the current on the inductor must get thru the resistance
this allow to see if your really charging the capacitance or just forcing the resistive side!