Hi Karl, If a small man (such as a leprechaun) were to sit upon your tesla coil would he be able to fire lightening bolts from the tips of his fingers?
Wow!....only 250 amp peak current to get nearly 5 foot sparks from a secondary of around 15 inch or so?....you should document it in the project section of 4HV.
The trick is the tuning. I tune the primary way below the secondary. The result is no break out at all. Then you turn up the repetition- the breakout starts to load the coil and the secondary frequency drops -this brings them in tune a bit more = more streamer growth etc etc Coupling is 0.185 for this coil, I can get more than 5 feet with a different torroid. I'll be at Cambridge next month to demo it.
Main change is to make sure the heatsink is not allowed to float about too much with respect to the backs of the igbts- i use a 600v gas gap- you can see it light up when there is an earth strike. To stop the primary strikes being a problem I increased the sensitivity of my current limit to detect the narrow pulses and latch the transistors off.
hhehehe its farting
samssoftwareuser 2 years ago
TÖK JÓ 5/5! xD!!!
Pujc 2 years ago
Hi Karl, If a small man (such as a leprechaun) were to sit upon your tesla coil would he be able to fire lightening bolts from the tips of his fingers?
JIMBOS99 3 years ago
Cool.....i look forward to seeing it in action at Cambridge!
Mel
bennem1 3 years ago
Wow!....only 250 amp peak current to get nearly 5 foot sparks from a secondary of around 15 inch or so?....you should document it in the project section of 4HV.
I take it that your coupling is high?
possibly around 0.2 or more?
bennem1 3 years ago
The trick is the tuning. I tune the primary way below the secondary. The result is no break out at all. Then you turn up the repetition- the breakout starts to load the coil and the secondary frequency drops -this brings them in tune a bit more = more streamer growth etc etc Coupling is 0.185 for this coil, I can get more than 5 feet with a different torroid. I'll be at Cambridge next month to demo it.
kimladha 3 years ago
The gas gap stops the transistor insulators breaking down on a ground strike.
I didn't turn down the current limit- I differentiate the primary current- this makes it more sensitive to spikes.
I don't use a GDT, i'm using an IR2184 drive chip!
My primary peak current is only 250A
kimladha 3 years ago
so...you connect the IGBT heat sink to earth via a 600v gas gap and turn down your over current protection?
Do you also use a common-mode ferrite bead
on the primary of your GDT to help stop noise going back into the driver electronics?
What sort of peak current are you pushing to get that sort of spark lengh?
I've seen your coils in action and amazed at
how you never have any blow out....thats good design on your part!
bennem1 3 years ago
Hi
Wow....really impressive!
Is that the secondary coil you demo'd at the Cambridge 'thon?
What did you do to solve primary strikes causing IGBT failure?
Any circuit diagram?
once again...imprssive results for such a small coil!!
Mel.
bennem1 3 years ago
Main change is to make sure the heatsink is not allowed to float about too much with respect to the backs of the igbts- i use a 600v gas gap- you can see it light up when there is an earth strike. To stop the primary strikes being a problem I increased the sensitivity of my current limit to detect the narrow pulses and latch the transistors off.
kimladha 3 years ago
why you change the frequency alternately?
MOJTABASHOMAL 3 years ago
Wow that's really impressive, where can I buy such a realistic laminate floor?
JIMBOS99 3 years ago