Greetings everyone,

Today I am building out my first post describing my work building a Plasma Torid experiment.

I will break this initial post up into a few sections, as I am hoping to use this as a repository of information, discussion, design ideas, and eventually a fully updated build log.



Picture courtesy of Zerg Labs
(Not my actual project)


// 1-2 L Borosilicate Glass Globe filled with Xenon //

A 2-liter, borosilicate glass globe, evacuated and filled with Xenon.
In the US you can find these by Wayne Strattman
https://strattman.com/
They are not listed on his official designs, but you can check his price sheets, or call him directly to ask how many he has in stock.
He only had a single 1L globe, and a few of the 2 L globes left last time I spoke with him, and lead times are 3-6 months.

EU/Russia you can contact
Zerg Labs

has quite a few options available, including pre-built with power supplies, and custom shapes and sizes.
https://teslacoil.pro/en
http://www.катушка-тесла.рф/
I do not know how the pricing, quality, or other aspects compare.
I am just trying to share other vendor options, as I know several of you are on that side of the Pale Blue Dot.

// CIRCUIT DESIGN  //

Circuit Design
This is the section that I will need the most help with, and the entire reason I am here.
Most everyone here is much smarter than I am in this, so if I do not use the correct terminology, or sound completely bonkers, just let me know.
I am here to learn, grow, and build this as a collaborative project with the community.

The initial design credit goes to Steve Ward, as his tremendous work in this field cannot be cited enough.
Class E Self Resonant Oscilitaing power amplifier

Standard Class E Self-Oscillating power circuit:
https://docs.google.com/document/d/1-jMPQOSs6-Flp181TTa8cNMSs2XumzDEahg9DVD0hKk/edit?pli=1

Sky Guided - Version .02 Circut





// Links //

The last section in this first post is a series of references to people who have created one of these builds.
This is not all-inclusive, and I know that I have missed some designs.
These are simply designs that I have found interesting and may aid in the overall development of the build and design.

BackMacSci
This was the initial design that I found.
He is younger and his circuit is one of the simplest in terms of design, but it works.
He is actively working on learning Plasma Theory and has recently also built a plasma spiral tube.
Leave it to the younger generation to inspire an old fart like myself to build new things.
https://www.youtube.com/@BackMacSci



Zerg Labs
These guys have a massive amount of work done on this topic
I am probably not giving enough credit, to them, so please check this out.
Especially for those of you on that side of the world.

https://www.youtube.com/channel/UCRKfNzc7-524yD8nlyZC5Zg


Integza
He has built one of these, but seems as if he is trying to market and sell them now as pre-built.
Looks like he is partnering with Zerg Labs as well for his build.
https://www.youtube.com/@integza



Sky Guided
This is one of the newest designs, and she is actively working on building this.
She goes into quite a bit of detail regarding the circuit design and working theory.
This is worth checking out.
https://hackaday.io/project/194683-plasma-toroid-sky-guided-pcb-edition
This is the most detailed, current, and up-to-date work on this project by anyone thus far.
If you are going to explore only a single link in this post, this is the one to read.
I learned quite a bit about the design and theory of the operation of this design from her explanations.
I should almost call this required reading.

Huxman
Only a single video here, but one of the best explanations of the circuit theory.
I would love to reverse-engineer this design and incorporate her upgrades into my circuit.
I have attempted to discern the circuit schematics, but I am having trouble with this one.
I hope there is more progress with this design.



// Further Research and optimization. //

After doing loads of reading on the circuit itself, I have found several papers where the Class E oscillator design has been iterated upon.
A few of these papers go into great detail about how to mitigate the sensitivity of components used, and how to select components to increase the efficiency.
I found several other papers as well, but they were locked behind a paywall, or in paid scientific journals.

https://www.researchgate.net/publication/326616551_A_Self-Tuned_Class-E_Power_Oscillator

https://www.researchgate.net/publication/322072074_A_Class_E_Power_Oscillator_for_678-MHz_Wireless_Power_Transfer_System

https://people.physics.anu.edu.au/~dxt103/160m/class_E_amplifier_design.pdf


// Theory //

(Warning, I may be wildly incorrect and these are simple observations based on what I have seen.
I have no supporting measurements to back any of this up.)

From what I have observed, this device works quite a bit similar to the functional relationship of the Primary and Secondary coils in Tesla coil circuits.
The exception is, that the Secondary in this case is the Glass Globe and Xenon.
With this being said, the plasma itself appears to be an inductive load, which is not a fixed figure, but its Impedance, resistance, and voltage drop can change drastically, depending on the state of the plasma.
From my work in Audio Amplifier design, this 'Load' is akin to a physical speaker to me.
It receives the driving current, it performs an action (which takes TIME) and then it changes state drastically, altering the load state.
In most Solid State designs, I have seen loads described as a single linear calculation, but in this case, we must learn as much as we can about the load we are driving, in order to properly drive it.

Some of my plans are to add things like an optical sensor, and heat sensor/thermistor, and to measure the circuit before and after the load stage, to get a better understanding of what is actually happening within the plasma.
Other things I would like to do, much later, would be to optimize the Load Time, to ensure that the circuit operates as cool and efficiently as possible.
I would then like to experiment with different waveforms, which will affect load time, as well as frequency tuning, and optimization.
At that point I am hoping to achieve a little better overall 'control' of the feedback loop of the plasma, to enable us to control/contour its size/shape/intensity, etc.


// Further Experimentation //

The reason I called this a Dual / Stereo Class E Oscillator, is that I plan on building the physical circuit twice, duplicated/mirrored.
Then I would like to build a second, secondary coil on the opposite side of the glass globe, and use the inverse of the signal from side A to Side B.
I would call this 'Stereo' in amplifier design, but no idea what the actual term for this is in circuit design.


// Closing //


I hope this has been a good read for all of you, and thank you for taking the time to read through my ideas today.
If you have anything to add, contribute, or correct, please feel free to let me know.


"Be Excellent to Each Other"
Max
Omgigatron