Microwave inverter hack: HV power supply
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- Опубликовано: 17 сен 2024
- Build a complete high voltage DC power supply using a Panasonic microwave oven inverter. Useful as a plate transformer for vacuum tube Tesla coils, radio transmitters, etc. Replaces the old iron MOT.
Great stuff! You have built a nice little unit & gone above and beyond to supply all the information required to get one of these things fired up. Very good! Thanks for sharing :)
Are you still out there Poultonm? These 2 videos are among the best ever, informative, helpful and motivating. Please do more on whatever other projects you've been in to. In 2011 nobody expected such treats on YT and few actually searched for them but now you would have an army of appreciative minions.
Maybe I will...
This is amazing. I was wondering why mine didn't work and you explained it all so well. (Needed a signal 220Hz signal.) Thanks also to Poultonm for that. I really like your mods and appreciate the help you've given me even 8 years after you posted this video. :D
Very useful, thanks. Some good safety tips in here. For the IGBT thermal solution, I'd feel a bit safer with an internal heatsink plus a fan, so even if the insulating pad fails you'd still be fairly safe. I'll post a video reply with my results...
Oh it auto-shuts-down alright. When the IGBT arced to the case it immediately stopped working completely. I'm amazed it didn't damage anything. Keep in mind that the power supply is designed to use the chassis as the secondary return conductor since a magnetron drains charge to its case. Unless you do a lot of work rewinding the transformer, the output is not isolated and the chassis is used as the current-carrying return for whatever your high voltage load is.
the insulating compound you have used for the IGBT becomes conductive with high voltages. In the high voltage industry, these materials are called "semi conductive". Materials like carbon compounds which are normally a dielectric (dielectric is an insulator) using lower voltages can be semiconductive with high voltages, however, they can only be identified as semiconductive using a hitpotential test set or with what's called a Megohmeter or Megger (this megohmeter is not like a normal multimeter that tests the resistance using a function to do so in the megaohm range , as they normally only push 3-5 volts through the leads to test these resistances) The Megger uses high voltages to test the impedance of these material in megaohms by pushing specific voltages in the ranges set by the meter. These levels could be 1200 volts up to 15,000 volts.
Yes, you're right of course. I tend to be overly paranoid about these things, so I'd like some degree of safety even if grounding fails (I was also thinking of auto shutdown on faults like said isolation failure or arcing to case).
The case is grounded, so if the isolation fails it fries the circuit but not the user. Proper grounding of the chassis is very important on any high voltage equipment like this. An internal heatsink and fan would be a fine solution, but requires a much larger case.
My bad, wasn't clear enough. I meant arcing to the case via the output, not via the IGBT. My initial idea there was to separate the inverter chassis and the "user accessible" outer metal chassis. The thought was to bring out the inverter chassis to the front panel as the designated return point, and join the inverter chassis and the outer chassis through a suitably rated low value resistor to detect any current flowing to earth through the outer chassis. Just brainstorming aloud here :)
Hi there poultonm: another great informative video, any chance of doing a short video on connecting the control wires to a 555 timer or a 1k resister!! as i think it would help a lot of other people out besides my self. Thanks.
Good, I have a Dud Panasonic invertor microwave in the basement, bloody invertor POS. There are multiple websites about these horid Panasonic microwaves and how to repair them, some re-engineering would be a good thing because the certainly didn't get it right the first time around.
Whats on the 3 signal wires to the MW board? 220hz sig, ground, and what else? My exp goes back yrs with the big transformers, now I need to retrain on these.
Nice modification! Can you show it in action too?
Dude, I hope you have some safety gear for electrical stuffs.
Well his last video was 8 months ago so it's safe to say he made it at least 7years without a mishap 🙄
yeah but will it give yoy the same ramped halfwave supply for the vttc
Which Panasonic model have you used for this setup?
Hello Dear Inverter Enthusiasts
I have been designing a controller for a National inverter board with two IGBTs and I have not yet concluded to the exact timing for the duty cycle because I do not know the transformer and magnetron’s parameters.
Any suggestion to tackle this problem would be highly appreciated.
Thank you for taking time to read this script.
Please can I make induction heater from the microwave?
Hi i have stripped a Panasonic microwave 1000w as i was going to build a welder but turns out the microwave is an inverter model so dont think i an use it for that but i have all the parts which are no good to me and have not been touched just stripped from a fully working system if you would like the parts pls msg me as they are no use for my projects and sounds a bit scary tbh.