If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.
Special Thanks To:
Aaron Holmes
Aaron Wheeler
Adam Horden
Alan Scrimgeour
Andre
Andrew Haynes
Anonymous000
asabase
Austin Weil
barney
Barry
Bert Hickman
Bill Kukowski
Blitzorn
Brandon Paradelas
Bruce Bowling
BubeeMike
Byong Park
Cesiumsponge
Chris F.
Chris Hooper
Corey Worthington
Derek Woodroffe
Dalus
Dan Strother
Daniel Davis
Daniel Uhrenholt
datasheetarchive
Dave Billington
Dave Marshall
David F.
Dennis Rogers
drelectrix
Dr. John Gudenas
Dr. Spark
E.TexasTesla
eastvoltresearch
Eirik Taylor
Erik Dyakov
Erlend^SE
Finn Hammer
Firebug24k
GalliumMan
Gary Peterson
George Slade
GhostNull
Gordon Mcknight
Graham Armitage
Grant
GreySoul
Henry H
IamSmooth
In memory of Leo Powning
Jacob Cash
James Howells
James Pawson
Jeff Greenfield
Jeff Thomas
Jesse Frost
Jim Mitchell
jlr134
Joe Mastroianni
John Forcina
John Oberg
John Willcutt
Jon Newcomb
klugesmith
Leslie Wright
Lutz Hoffman
Mads Barnkob
Martin King
Mats Karlsson
Matt Gibson
Matthew Guidry
mbd
Michael D'Angelo
Mikkel
mileswaldron
mister_rf
Neil Foster
Nick de Smith
Nick Soroka
nicklenorp
Nik
Norman Stanley
Patrick Coleman
Paul Brodie
Paul Jordan
Paul Montgomery
Ped
Peter Krogen
Peter Terren
PhilGood
Richard Feldman
Robert Bush
Royce Bailey
Scott Fusare
Scott Newman
smiffy
Stella
Steven Busic
Steve Conner
Steve Jones
Steve Ward
Sulaiman
Thomas Coyle
Thomas A. Wallace
Thomas W
Timo
Torch
Ulf Jonsson
vasil
Vaxian
vladi mazzilli
wastehl
Weston
William Kim
William N.
William Stehl
Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Registered Member #146
Joined: Sun Feb 12 2006, 04:21AM
Location: Austin Tx
Posts: 1055
The DR part is mainly just a convenient way to get a higher system Q without having to store all the energy in the secondary... that is to say, you could make a single resonant coil, but its gotta be much lower impedance to work as well as a DRSSTC would.
I think a regular SSTC (single resonant) would work OK if designed right. The secondary impedance needs to be a lot lower than what most people use, that means lots of toroid capacitance and very little secondary inductance. Id probably try getting the reactance at resonance to be less than 20K ohms as a start (it might benefit from being even a lot lower depending on the drivers output impedance). Keeping the Fres above 320khz or so seems to allow for the branchless spark growth, which seems to primarily be due to lower voltage spark growth. Going higher than maybe 360khz seemed to have no benefit in my experiments, though may be useful because it lowers the required output voltage per spark length. My straight sparks needed about 65kV peak when grown to 4 feet, at 365khz.
Steve Ward's original QCW used DC bus voltage modulation without any current feedback, so that is the approved way of doing it. My experiments with current feedback were none too impressive, and I plan to stop using it.
I think i got lucky that the bus modulation worked so well at controlling the spark power. If the DRSSTC was a stiffer voltage source, it wouldnt work well at all, and then i think current regulator would be better. Anyway, dont stop using your control technique until you try the higher frequency coil first! Or at least mess with the ramp parameters to be sure it doesnt work.
Registered Member #598
Joined: Thu Mar 22 2007, 07:41AM
Location: Poland
Posts: 6
I tested my half bridge SSTC with a 580 kHz seconadary and I achieved up to 1 foot sword-like sparks. I don't use modulator, coil run with a synced interrupter at half wave rectified mains.
Registered Member #1403
Joined: Tue Mar 18 2008, 06:05PM
Location: Denmark, Odense C
Posts: 1968
hvman wrote ...
I tested my half bridge SSTC with a 580 kHz seconadary and I achieved up to 1 foot sword-like sparks. I don't use modulator, coil run with a synced interrupter at half wave rectified mains.
I have been and am working on a DRSSTC version of the same, a synched interupter to conduct for the first 5ms of the 50Hz period, but its trapped in a box while im moving :)
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.
non-DR QCW's
