Author Topic: Variable Voltage Amplitude Control  (Read 15481 times)

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Re: Variable Voltage Amplitude Control
« Reply #16 on: April 15, 2009, 05:15:31 am »
alright one last thing......patent WO 92/07861 has every circuit he used tell how they interlock.....and i think he was using some sort of fet because i see Vdd and Vss in the schematics.....

everyone needs to read that patent.....

http://encyclobeamia.solarbotics.net/articles/vxx.html

well from looking at his circuits it seems stan wasn't using a mosfet but a Bipolar junction transistor

i hope this is right i will keep looking into it.

http://www.electronics-tutorials.ws/transistor/tran_1.html

i think this might be the way to couple and join the driver with the amplitude signals properly.

edit: hell yeah keyword ( "Attenuates" the signal )

so no mosfets but BJT!...look at the "The Common Base Amplifier Circuit" i think that is how it is to be connected to the primary coil.

now i just have to find the right specifications for this transistor.
« Last Edit: April 15, 2009, 05:44:49 am by kinesisfilms »

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Re: Variable Voltage Amplitude Control
« Reply #17 on: April 15, 2009, 10:05:01 am »
if your mosfet is blowing, why won't you use a recovery diode to protect it?

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Re: Variable Voltage Amplitude Control
« Reply #18 on: April 15, 2009, 17:09:22 pm »
Quote
hmm......what did stan use to combine the driving pulse and the voltage amplitude.....i have it hooked to the primary coil as in the diagram but i am using a mosfet in between and having the grounds go through that....


damnit....i can try a larger mosfet....but i would have to order it and wait for it.

if your primary coil impedance is small, no mosfet or IGBT can handle the load. To get around that use a half-bridge circuit. it is similar to the circuit used in induction hobs and furnaces.
Look it up.
« Last Edit: April 15, 2009, 23:48:24 pm by stevie1001 »

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Re: Variable Voltage Amplitude Control
« Reply #19 on: April 16, 2009, 01:07:31 am »
hey yaro i tried looking up the induction hob circuits with no luck.

also i got 2 BJTs and am goign to try some conection types.

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Re: Variable Voltage Amplitude Control
« Reply #20 on: April 16, 2009, 02:42:27 am »
no luck......so i am going to go for a really large mosfet.

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Re: Variable Voltage Amplitude Control
« Reply #21 on: April 16, 2009, 04:43:23 am »
Make sure you do not exceed the mosfet's power ratings.

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Re: Variable Voltage Amplitude Control
« Reply #22 on: April 16, 2009, 06:13:11 am »
haha....of i have been exceeding the breakdown voltage with my current mosfets which are rated from 40-60 volts.....

i ordered 2 mosfets with breakdown voltages of 600 volts.....and continuous current drains of 15 amps.......hopefully this works.

becuase just as the signal starts to form inside the water capacitor my mosfet gives out.

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Re: Variable Voltage Amplitude Control
« Reply #23 on: April 19, 2009, 20:23:06 pm »
well i got the mosfets and hooked them up.....the signal forms beyond what the other mosfets broke down at....but it never fully forms.....it just stops and i can't go beyond it and there are no bubbles at all....i can only increase the wattage used.....and still nothing.....this is the last step to replicating this......if we can just overcome how he was interconnecting the pulse driver signal with the variable voltage amplitude signal it will be completed......

would any of the electronic wizards like to explain to me or help me to understand what is going on in this circuit.

(http://i2.photobucket.com/albums/y2/kinesisfilms/hmmm.jpg)

i am coming to the point where i would rather just gate a variac rectified signal.....but once again more and more money.....if only my function generator could pump out a tad more power and actually be used as a power function generator.

this is what it comes down to.....the connections on the primary coil.