[SOLVED] high voltage without winding a coil

[Zak28]

Whats the simplest way to obtain corona from a spool of 26-32awg wire without actually unwinding it? The spool has both ends accessible and I tried chopping ~5amps DC with ~2 turns around around the spool at varying frequencies and nothing came out. The spools are 8oz. The primary voltage doesn't matter since the impedance is very low, only when the frequency rises does the voltage drop rise - also however high frequencies are not optimal for the spool since its inductance is likely enormous and I did try 20hz - 100khz and still nothing came out. The spool was not connected to anything it was open on both sides. Perhaps the inductance is too large but I am not sure what the issue was.

 

[smijesh]

Corona proportional to applied voltage and atmospheric pressure.
For obtain corona you can increase the applied voltage on the spool or decrees the pressure

 

[Zak28]

Corona proportional to applied voltage and atmospheric pressure.
For obtain corona you can increase the applied voltage on the spool or decrees the pressure

The issue appears to be the spool has far too much capacitance for 26awg measured value ~1.22nF @ ~68mH, the primary voltage cannot be stepped up since its far too low an impedance.

The spool just rings at ~80-140v perhaps there is a method to circumvene the spools capacitance.

 

[smijesh]

I will give one more solution.
Insert iron bar or stacked lamination(I Core) in to the centre hole of the spool, it will increase the impedance and you can increase applied voltage

Or place the spool on cut C core (Silicon steel or other magnetic materials) this is more effective

 

[Zak28]

Simulation shows the voltage substantially raises from the ~80-140v to ~1.4kv by chopping at spools optimal LC frequency.

I tried the spool in a U I core which I made from from a MOT and chopped at optimal LC frequency and no corona. Increasing the frequency is the only thing which raises the primary voltage @ 1MHz its ~15v at primary coil.

 

[smijesh]

You have to consider potential difference in between two adjacent conductor, the separation between two conductor is also one of the main contributor for corona, Corona is a phenomena just before arcing between conductor