So again I have a common 30v 5A capable supply feeding a ZVS driver which has its power pulse width modulated using a TL494 and switching mosfet. Rather than boost/buck that supply using regulated circuits (which cost money) I can use a ZVS driver to boost the voltage with a basic easy to wind HF transformer and also get much higher amperage than a 5A regulated DC supply would normally allow directly (at lower voltages of course). With the windings I have I can still power a flyback from the output on the AC side. The running frequency of the output transformer and the way the pulses are occurring over time make it so the 110VAC output feels like a tingle at most. The supply has worked well so far even for powering these Tesla coil circuits and I haven't needed to create some kind of optocoupler deal. I blew the TL494 on my external PWM feeding my large tower over 20V but the one in the supply is fine thanks to at least some isolation at the transformer. I didn't realize it was a thing til looking at some older videos but the PWM on the Slayer Exciter circuit is a cool way to push more power. My big tower is really my main concern when it comes to running from power supplies since it's a stray RF beast at over 12v that doesn't much care what kind of isolation I provide so long as there is some capacitance there. Being able to find resonance at the lower power levels is important which is why I want to test setups before trying to build bigger drivers. The easier it is to get it to oscillate the easier it should be to get gate-driving feedback in a high power setup without amplification. I've been impressed at what I can crank a MJE3055T to without burning it out. A quad transistor setup using those would be pretty impressive and inexpensive. They can handle upwards of 45V on the basic circuit but after that I wouldn't bet on it. I didn't have enough to push to their deaths voltage-wise. When it comes to pushing a little more power from single fets the IRFP260Ns have worked well for me and seem to be a staple. The 460's not so much, they might be too slow and I'd only use them for general purpose high power switching. Hard to say since I sourced them for like a buck from Aliexpress months ago. The best components are probably going to come from junk board pulls and I get the best fets from modern TV power supplies. I've pushed a few with the basic Slayer Exciter circuit to 70V without problems.The way I see it if impressive results are drawn from the proper transistor at low power, then similar results should be seen from the proper mosfet at the same power and even better at more power. If just pushing/pulling works well then pushing and pulling should work even better at the half bridge. At the full bridge and double voltage we should really start seeing the beef. If my half bridge setup at low power is not cranking the same impressiveness as a single transistor setup at the same power then I need to start over.
The most impressive low voltage circuits I've seen so far are the Skori SSTCs and mods. They really push what a small coil is capable of when it comes to inverting at high voltage. I'm still trying to figure those things out before going to a half or full bridge driver pushing 100VDC or more. I've been trying to dig through old junk to find some iteration of a proper mosfet gate driver with no luck and see the Skori circuits are not even using them and a TefaTronix mod has the frequency feedback going directly into a gate drive transformer. I first have to think the reason a lot of coilers are using 12v powered gate drive amplification to feed the GDTs is because they get much better results that way, but just look what the results of a relatively naked switching signal directly from the base of the secondary is doing for the Skori circuits. Instead of trying to make one of these random drivers work which all have set internal frequencies in the oscillators I might try directly feeding a GDT with the secondary feedback like TefaTronix has done. He was kind enough to give me some insight in that it's probably the low gate charge on the drive mosfets making this possible and playing with the GDT turn ratio may even allow for a fet with a higher gate charge to work.
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