Building a QCW Tesla Coil
Вставка
- Опубліковано 5 жов 2024
- In this video, we explore how to build a quasi continuous wave or QCW Tesla coil. These devices are technically challenging to build but well worth the effort. They are basically DRSSTC Tesla coils with a ramped voltage input and with much longer on times compared with traditional DRSSTC Tesla coils. The first QCW Tesla coils were built by Steve Ward and refined by others such as Loneoceans. The idea for building QCW coils came from observations that VTTC staccato controlled Tesla coils with unfiltered mains input produced beautiful long straight sword-like arcs.
Never thought I'd see a QCW video that wasn't just a demo! Congrats on the build man, hopefully I'll be able to join the QCW club someday!
Thanks man! You’ll be in the “club” soon for sure! Your work is awesome!!
Great video
Yes the loop noise can get extremely tricky. Shortest possible connections for the main feedback loop of course and running the trunk through a high permanency ferrite ring just before feedback entry on the buck controller will do the trick. Getting the buck back into loop and adding a few extra foot to the spark! Ggy made note of this I believe, it's just not shown in his schematic. We greatly appreciate your explanations and illustrations. Big salute to you and Loneocean's both!
Thanks a bunch. Yes that’s definitely true. I had long connections for the test setup which made the buckverter signal look coarse and messy 😁
I had to double check just to make sure and you indeed have this amazing ramp. I wish I could figure out how there is so little ripple. I also just noticed you have quite a bit of EMI filters which is funny because I recently bought a bunch and started snapping those things everywhere and saw quite a noticeable difference in the QCW.
Interesting! I was under the impression that the buck controller was needed for stable operation of the buck. Great vid btw!
Thank you! It was fun. Will plan on doing a final build and follow up video soon!
very nice work! perhaps that method can be used to drive a HHO cell with resonant efficiency... the ramp is a method Stan Meyer used and not many people have been able to replicate it. I have and it has to have a larger gap than everyone is usually using.
Thanks really appreciate it!
Love the video great output⚡⚡
Thank you!!!
Awesome and informative video, thanks! Do you know why QCW tesla coils like a higher coupling coefficient for the primary and secondary? I'd imagine all tesla coils would, but is that not true?
Interesting question. Seems like unlike DRSSTC, QCW coils are not really true DRSSTC- they are operating in upper pole mode
@@BrianDhvTinkerer what is upper pole mode? Sorry that I'm unfamiliar with the terminology 😅
@@inventorbrothers7053 basically a tesla coilin normal DRSSTC mode is a Resonant system operating with quarter wave across the coil with the bottom of the coil a zero point on the quarter wave and the top part of the coil the maximum part or voltage of the quarter wave of a full wave AC cycle. This resonant frequency gives maximal amplitude when tuning the secondary coil and top load combined. With a normal Tesla coil, as spark growth occurs, the capacitance of the top load effectively increases which decreases the resonanant frequency of the secondary. So typically in a DRSSTC situation, the primary coil resonance is set approximately 20% lower frequency than the secondary resonant frequency. As spark growth occurs, it drops the resonant frequency of the secondary so that it becomes identical to the primary resonant frequency. Then the coil is now in a double resonant situation. Massive amounts of energy can be transferred from the primary tank to the secondary coil as the impedances of the two systems become identical with spark propagation. This is sometimes known as spark “loading”. This is the true DRSSTC mode. The coupling between primary and secondary with DRSSTC needs to be low because of the way the energy is transferred. With a QCW system, things get much more complex. With a high coupling coefficient between primary coil and secondary coil, the two coils function together as a single resonant system in upper pole mode. The resonant frequency of both the primary and secondary coil jump into a different frequency, which is typically higher than both of the separate resonant frequencies which is known as the upper pole. My guess is that this is some kind of harmonic. However, when the two coils operate like this, there is maximal energy transfer. Because of the high coupling between the two coils, there are issues with secondary to primary strike. This is alleviated by ramping in the bus voltage essentially going from zero to voltage of around say 340 V. This results in a spark, which grows as the ramp increases. As the spark grows, the frequency of the Resonant system drops for both primary and secondary.
@@BrianDhvTinkerer okay that makes a heck of a lot more sense. I didn't know before that the secondary LC circuit in a DRSSTC was tuned higher to account for resonant frequency drop during large spark discharges. That's actually brilliant. Thanks so much for your detailed response! 😁
I was having the same issue with the buck modulator. I am going to run it straight from the generator later. Crossing my fingers there is no interference
I was surprised how well it worked without the buckverter!
Well, I ran some tests connecting the LC straight to the gate driver and I did get a ramp with minor interference. I attempted another build of the loneoceans buck modulator to no avail! It just doesn't work for me. I utilized the same setup as Magneticitist and so far its working well. @@BrianDhvTinkerer
Great, now I want to build QCW...
Thanks man! They are really interesting coils. I built 2 so far
I tried to vary so many things and the electronics is not the biggest problem but i did not succeed in making a coil that works so well as yours. My problem is mostly the coil itself, the secundairy with topload. Mine are always resonating far above 3 or even 400kHz and above a certain toploadcapacitans the sparks decrease. But above ca1400 turns it also only get less, so how do you get such mighty sparks with such a compact coil?! I mean, can you please tell me your secundairy how many turns and the thickness of the wire you used and diameter and so? I tried so much, full bridge(8x irfp460) on our 240v (Netherlands) but it works less well above 2-300kHz
Try 12 inch diam topload x 3 inch thick
Use 6 or 7 inches tall x 3.5 inch wide secondary wound with 34 gauge wire on PVC)
5 inch diameter 13 turn primary wound on non PVC material
12 nF MICA capacitor
Ramp in the DC using buck and Finn Hammer arduino code
The coil jumps pole from 250 kHz to 340kHz when it running correctly- Output suddenly takes off like crazy.
Here’s a run- I’m not even using a buck modulator circuit. I should be able to get more output if I set it up with a buck modulator.
IRFP260N will work but you are limited on your voltage to not more then 100-120V. This setup is being run with SKM100GB at 340kHz way above their rated frequency. Also you want to be able to run at least 100A and IRFP will fail at 50A
Here’s a test run:
QCW Ohio TeslaFest 2024
QCW run 220 V AC
ua-cam.com/video/K7AFmQMpBN4/v-deo.html
Hope this helps
Brian
@@BrianDhvTinkerer
What do you mean with "jumps pole ?" Between two frequencies? Does that mean it hás to be with an antenna or secundairy current feedback? Will it not work with just one adjustable frequency?
And about the secundairy, i calculated your values to our metric and is it right that 6"/34gw~700turns? And most of all, you named 12nF so indeed double resonance but thats with half bridge on 120v? Or full bridge but how can that with the capacitor because with primary resonance i can only get my fets in spec working in half bridge. (Ow i use irfp460 instead 260 so they are 500v and pulsed 80A but i use 4in parallel top and 4lower half. The current and voltage are not a problem on 230v half bridge or fullbridge without capacitor in series with the primary. I never used primariries more then 4-6turns but that will change after learning from your first answer. I hope that you can fill in these last gaps in my understanding i asked here in this first half of this (maybe a bit too long) text?
This jump in frequency happens with these ramp QCW Tesla coils and is explained on loneoceans website. What I have observed is that the frequency changes from the measured first harmonic of either primary or secondary to a combined frequency with the whole unit primary and secondary oscillating together as a combined or coupled unit. You need good coupling ( hence more primary turns) and current transformer feedback not antenna feedback
Heathcote Trace
Gibson Mill
Dane Park
Boyer Squares
Thank you SciTube, this was very fun and informative! Did you use any other sources for help or lessons while building this, or just loneoceans site?
Used a combo of loneoceans site, collaboration with ArcAngel, reading up on buck inverters, and just plain old experimentation 😂
Williamson Village
Gerhard Tunnel
awesome
Greenholt Valley
Yundt Underpass
Donnelly Greens
Smitham Ramp
Smith Spur
Kendall Brooks
Verna Mountains
Treutel Plaza
Lavina Stravenue
Anne Fields
Camden Meadow
Evert Court
Anjali Walks
Christiansen Plains
Leannon Port
Lind Canyon
Annamarie Rapid
Sabrina Dam
Reilly Dam
Lue Plains
Ross Track
hi. how you can measure current primary just with one channel of scope? 🧐 can you explain to me please?
Using 1000:1 step down transformer 1000A-->1A
With 10 ohm burden resistor across the output of the transformer V= IR = 10 x1 = 10V. So a peak to peak voltage of 20V on the scope from the current transformer with this burden resistor would corresponding to 1000 A. A pk to pk of 10 V would be 500A etc
Rutherford Via
Cole Terrace
Moore Isle
Seamus Road
Carmela Glen
Zoie Wells
Isn't that an H bridge?/
Sure is- works very well
Destini Burg
Spinka Radial
Stokes Corner
Jayda Harbors
Ibrahim Turnpike
Runte Garden
Batz Squares
Alexys Valleys
Dexter Crossing
Arno Garden
Kiehn Point
Alphonso Port
Justyn View
Macejkovic Path
Lexie Spur
Собери Квазинепрерывно волнистую двухрезонансно твердотельную катушку Теслы
Jlaser did this in his thor hammer build
Beier Shoal
Dicki Pike
Beer Pass
Amina Club
Haag Rest
hello，I need a circuit diagram❤
Based on
www.loneoceans.com/labs/qcw/
It’s very hard to build a qcw btw, I suggest you don’t waste money on that if you know nothing to begin with (not saying you know nothing)
@@tinkeringwithhighvoltage that’s true! That’s what it makes it fun!
@@tinkeringwithhighvoltage OK，agree with you
@@youngk2495 from what he made, I estimated the costs to be somewhere around the 300-500usd zone (excluding all lab tools required for tuning and debugging), definitely not a great project for any low budget science fairs
Mettimi a posto i commodore malfunzionanti sono Biagio di balsamo e famiglia
Johnston Crescent
Judson Mall
Alexandra Divide