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Registered Member #599
Joined: Thu Mar 22 2007, 07:40PM
Location: Northern Finland, Rovaniemi
Posts: 624
Some time ago i got a hold of two of these transformers and finally decided to do something with them.
Basicly what i have is just igbt half bridge and Vco. Has anyone measured the self resonant frequency of the secondary coil? Mine peaks at 48kHz and the voltage rise is absolutely crazy. With 3 turn primary, and 12V input voltage to the half bridge (6V to load) i got corona fuzz from both HT leads and arc ignited about 50mm away
For normal arcing 25kHz seem to work ok. And 25kHz keeps my igbt brick happy too :)
Registered Member #11591
Joined: Wed Mar 20 2013, 08:20PM
Location: UK
Posts: 556
Kizmo wrote ...
Some time ago i got a hold of two of these transformers and finally decided to do something with them.
Basicly what i have is just igbt half bridge and Vco. Has anyone measured the self resonant frequency of the secondary coil? Mine peaks at 48kHz and the voltage rise is absolutely crazy. With 3 turn primary, and 12V input voltage to the half bridge (6V to load) i got corona fuzz from both HT leads and arc ignited about 50mm away
For normal arcing 25kHz seem to work ok. And 25kHz keeps my igbt brick happy too :)
You're driving these things with IGBT Bricks?! wow, should be able to push 'em hard!
Registered Member #8817
Joined: Mon Dec 17 2012, 05:16AM
Location: Australia
Posts: 110
Kizmo wrote ...
Some time ago i got a hold of two of these transformers and finally decided to do something with them.
Basicly what i have is just igbt half bridge and Vco. Has anyone measured the self resonant frequency of the secondary coil? Mine peaks at 48kHz and the voltage rise is absolutely crazy. With 3 turn primary, and 12V input voltage to the half bridge (6V to load) i got corona fuzz from both HT leads and arc ignited about 50mm away
For normal arcing 25kHz seem to work ok. And 25kHz keeps my igbt brick happy too :)
Registered Member #599
Joined: Thu Mar 22 2007, 07:40PM
Location: Northern Finland, Rovaniemi
Posts: 624
It is most certainly not healthy for the transformer. Can i ground one end of the HT coil? Do you happen to know the internal construction, which HT lead is closer to the core or is this multiply pancake style HT coil?
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Modern AC Flyback Transformers
