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 #2922
Joined: Sun Jun 13 2010, 12:08AM
Location:
Posts: 226
Hello! I'm developing my new big DRSSTC, it will use a full bridge of cm300 igbt, I want to put the OCD to thing like 1000A. My question is about drive this high gate capacitance devices.
What is the best?
- Drive with a step-down 2:1:1:1:1 GDT with 60v in primary and at tha gates of the cm300 30v?
- An active gate driver with high power P/N MOSFET, one per each gate, powered by SMPS?
And what is the best gate voltage to use with this cm300 igbts? 30v or 24v?? I don1t want desaturation of this with 1000A...
Registered Member #2288
Joined: Wed Aug 12 2009, 10:42PM
Location: Cambridge, MA
Posts: 179
I've done both a GDT and an active driver on CM200 and CM400 bricks. It is possible to do a GDT but it has to be really well designed. Even if it is, it's not going to be the fastest waveforms you can achieve. I've found the best to be P/N mosfet drivers on floating supplies.
Either way, I'd suggest 24V and not 30V. 30 is pretty high and could potentially damage the bricks. I now run -5V low, 22V high although admittedly I did once run 30V+. It's really not necessary to be that high though, especially if you have good rise times.
Registered Member #599
Joined: Thu Mar 22 2007, 07:40PM
Location: Northern Finland, Rovaniemi
Posts: 624
This is little something i have been working with. Driver is basicly Steve Wards universal driver 1.0
CM300DY-24H H-bridge, single GDT wound on 26mm OD ferrite toroid, 5.1ohm gate resistors bypassed by ultra fast diodes. Very simple and basic setup.
So far this thing has been pushed up to 1200Apk at 135bps with no sign of problems. Even inverter output looks nice and clean (no shoot through, minor amount of overshoot due to imperfect ZCS)
Registered Member #599
Joined: Thu Mar 22 2007, 07:40PM
Location: Northern Finland, Rovaniemi
Posts: 624
Its tradeoff between switching too fast and getting more transient junk to inverter output or switching too slow and burning ton of power to heat because of switching losses. Sure i could use lower Ron to get steeper rising edge but i dont see reason why since this setup works very nicely at 1200amps like it is.
Registered Member #2922
Joined: Sun Jun 13 2010, 12:08AM
Location:
Posts: 226
I will try 2 GDTs one per brick (half-bridge) and see the results.. The GDT drived with a IRF540/IRF9540 H-bridge. Maybe less resistance at the gate, like 2ohm..
Registered Member #2616
Joined: Sun Jan 10 2010, 01:00PM
Location:
Posts: 12
It is a common misconception that you need blistering fast edges in gate drive signal as it can and more or less will cause transients and ringing in switching circuits. Also remember that the switching devices are only in the true linear region for a very small portion of the slope on the gate-voltage waveform so the switching times are not the full 10%-90% rise- and fall-times of the gate waveform.
Predikter style phase lead driver is much better way to deal with switching (and logic) delays than torturing poor gates
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.
Driving CM300
