How many IGBTs = 1 successful coil / Tesla Coils / Forums

Welcome

Online

Members Birthdays:

No birthdays today

Next birthdays
05/04 Matthew T. (35)
05/04 Amrit Deshmukh (60)
05/05 Alexandre (32)

Contact

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.

Forums

4hv.org :: Forums :: Tesla Coils

« Previous topic | Next topic »

How many IGBTs = 1 successful coil

Move Thread

LAN_403

Josh Johnson

Thu Jun 14 2007, 04:59AM

Registered Member #793 Joined: Sun May 20 2007, 06:50PM
Location: Minneapolis, MN
Posts: 35

I just got my hands on 5 of these IGBT bricks.

I'd like to start on a small DRSSTC but this will be my first. I am going to burn through all the IGBTs before I get a good working coil?
I am going to play the safe route a.k.a blatantly copy other designs and I have had good luck with a regular SSTC. I like the fact that everything (all igbts and diodes) are in one place which will make for a more compact setup but if I loose one igbt the brick gets useless pretty fast. Also it looks like this module is hard to come by because no distributors have them in stock. So once I go through these 5 that's it.

Steve Conner

Thu Jun 14 2007, 08:51AM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

You'll probably not trash them all unless you are careless, or have a poor understanding of high frequency layout and bypassing techniques, or just get over eager and crank it up too much. :P Even if you do destroy all 5 modules, the H-bridge is only a small part of the labour of building a DRSSTC. You can just rebuild it with four TO-247 IGBTs.

Mjollnir

is still running on the same four IGBTs he was loaded with at the beginning.

Sulaiman

Thu Jun 14 2007, 08:53AM

Registered Member #162 Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3140

I'm not an expert (others may have better advice) but I think the important things are;
1) Make sure the interrupter (duty cycle controller) is working really reliably before testing any other part of the drsstc
2) Make sure that you ALWAYS set the interrupter for a low ON time when testing
3) If possible do all testing with a variac for the hv supply, start at low voltage and slowly increase the voltage in small increments, re-testing the drsstc at each stage.
During the ON time of the interrupter the primary current increases each hf cycle (resonant primary)
It doesn't take too many cycles to exceed the current rating of your output transistors.

Hazmatt_(The Underdog)

Thu Jun 14 2007, 05:52PM

Registered Member #135 Joined: Sat Feb 11 2006, 12:06AM
Location: Anywhere is fine
Posts: 1735

If you really want to protect your bricks from failure, you would add gating logic to your drive circuitry insted of having the off time control alone. This would maintain a minimum off time which accounts for the rise and fall time of the IGBT's. That way, no matter how low the off time is set, there is always the minimum default setting, and there won't be any shoot through.

Josh Johnson

Fri Jun 15 2007, 01:51AM

Registered Member #793 Joined: Sun May 20 2007, 06:50PM
Location: Minneapolis, MN
Posts: 35

Thanks guys, all great advice. Good to know there is a chance of making through the building/tweaking process and not loose too many IGBTs. Of course I was going to try these guys in a DRSSTC anyway but now I have a more optomistic outlook.

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob

Legal Information