If they are properly balanced and working withing their specified SOA range then yes.
Are you needing 1500 watts dissipation capacity or 1500 volts working or both? It makes a difference when you are specing a 57 amp 100 volt rated mosfet Vs a .425 amp 2500 volt tube.
I don't know if 1500 watts is enough or too much. I need to heat some 3/4" steel rods red hot and also some 1.25" pipe red hot to make metal parts. I have a couple of 810 tubes I just wondered if they would work.
I have some pretty large SCRs or something probably in the 600 amp range with 3/4" threads to bolt it to a heat sink. The bradded terminals are 1/2" diameter. No part number so I'm not sure what these are or if I can use them.
Of course you can, I did something very similar with a constant current source. Had all the N MOSFETs in parallel to help ease the load on any one transistor. Works like a charm!
So are you actually doing any numbers behind this concept or are you just tossing things together and seeing if anyone here thinks it might actually work?
Right now I am getting a strong impression that most of this is just toss and hope rather than calculate and construct.
So are you actually doing any numbers behind this concept or are you just tossing things together and seeing if anyone here thinks it might actually work?
Right now I am getting a strong impression that most of this is just toss and hope rather than calculate and construct.
I did my best to get this right but I would appreciate it if someone would check to see if there are mistakes.
I know from experience from putting transistors in parallel a small resistor is required on each transistor to prevent 1 transistor from trying to take the full current load of all 10. The 1.5 ohm resistor should limit current to 10 amps on each transistor with 15 vdc from the power supply. That should be 150 watts per mosfet.
I am not sure the zener diode can handle the Gate current of 10 mosfets. I might need a larger higher current diode or 10 diodes in parallel.
I did my best to get this right but I would appreciate it if someone would check to see if there are mistakes.
I know from experience from putting transistors in parallel a small resistor is required on each transistor to prevent 1 transistor from trying to take the full current load of all 10. The 1.5 ohm resistor should limit current to 10 amps on each transistor with 15 vdc from the power supply. That should be 150 watts per mosfet.
I am not sure the zener diode can handle the Gate current of 10 mosfets. I might need a larger higher current diode or 10 diodes in parallel.
You don't need more fets, you need thick water cooled tube for the working coil, a lot of parallel coupled caps for the resonant cap, higher working voltage, a fet with low rdson ...
If you put so many in parallel they will be slow to switch. Look at one like this: https://www.mouser.com/ds/2/149/FDP075N15A-348128.pdf
Instead of doing your own inductor use 2 of these 4mh in parallel. https://www.mouser.com/ds/2/358/typ_DENO-42113.pdf
When you say 1500 watts, do you mean the power in the part you are trying to heat?
I'm not sure you can get that much out of these designs, but you can probably get 500 or 600 watts.
PS. I don't think your new circuit is as good as the old center tapped one with the single inductor.