Welcome
Username or Email:

Password:


Missing Code




[ ]
[ ]
Online
  • Guests: 26
  • Members: 0
  • Newest Member: omjtest
  • Most ever online: 396
    Guests: 396, Members: 0 on 12 Jan : 12:51
Members Birthdays:
One birthday today, congrats!
GrantX (34)


Next birthdays
03/29 GrantX (34)
03/30 Adam Horden (39)
03/30 Mr.Warwickshire (23)
Contact
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.
Forums
4hv.org :: Forums :: Electromagnetic Projectile Accelerators
« Previous topic | Next topic »   

Is this a suitable thyristor for induction launcher?

Move Thread LAN_403
Quantum Singularity
Thu May 25 2006, 12:49AM
Quantum Singularity Registered Member #158 Joined: Sun Feb 12 2006, 09:53PM
Location: Central Ohio
Posts: 282
Yes... I have another SCR question. Because I am uncertain about my stud mount scr's holding up to a fairly high power induction launcher, I am thinking I might just use those for a reluctance coilgun were I will be dealing with multiple lower powered stages. So I am looking for a more robust scr for a multi-kJ single shot induction launcher. I have seen one and I thought I would post some of its specs here to see if anyone thinks it would work. It is extremely robust for I ratings but due to its original application I am not sure if it is 'fast enough'. Here goes:

MARCONI AUTOMOTIVE STYLE SCR CONTACTOR FROM WORKING PRESS WELDER

WELDING RATING AMPS RMS AT 100% DUTY CYCLE ------1200

SGL. CYCLE SURGE CURRENT ( ITSM ) ----------------------------10000

SCR VOLTAGE RATING ( PIV ) (VRRM )-----------------------------2600

THIS UNIT IS DIRECT WATER COOLED

The unit is complete with a housing with what appears to be 2 large puck scr's. It has large buss bars for connecting. The current rating alone tells me that it should take anything I can throw at it, under 2600V anyways. This unit is a little pricey but well worth it I beleive if it will work well for a few kJ induction launcher. Any opinions are appreciated.
Back to top
Self Defenestrate
Thu May 25 2006, 03:20AM
Self Defenestrate Registered Member #87 Joined: Thu Feb 09 2006, 01:36PM
Location: San Jose
Posts: 191
Sounds fine to me. Hit the gate hard, and check any insulation on the clamp. Nothing worse than an unexpected discharge.
Back to top
Plasmaniac
Thu May 25 2006, 10:03AM
Plasmaniac Registered Member #206 Joined: Sat Feb 18 2006, 03:17PM
Location:
Posts: 72
My first induction coilun desing blew a 1,1kV 10kA surge SRC at something around 1kV and 40µF because the kickback diode was killed the shot before, so make sure you use a suitable one.
Back to top
Quantum Singularity
Thu May 25 2006, 01:59PM
Quantum Singularity Registered Member #158 Joined: Sun Feb 12 2006, 09:53PM
Location: Central Ohio
Posts: 282
Wow, it seems like it would take a lot to blow an 10kA rated scr.... epsecially with only 20 joules. Is that right...just 40uF and 1kV? Anyhow, I will definately use large diodes. The current ones I have are rated 85A continuous and 800V I beleive. Cant remember the surge rating but I beleive it was atleast 1kA. I have 6 of them and would probably parallel all of them for a couple kJ bank. But I am still looking for larger ones if I happen to find a good deal. The ones I have a 'standard recovery' power diodes (stud mount). I was concerned because I noticed some folks here have used high power ultra-fast type diodes. But the 'ultra-fast' is a rating of the turn off time right? For clamping we are primarily concerned with turn on time so the diode can provide a short across the coil to keep the voltage from rising very high. And the conduction time even in a standerd recovery rectifier is much quicker that its turn off time - correct?
Back to top
Electroholic
Thu May 25 2006, 03:52PM
Electroholic Registered Member #191 Joined: Fri Feb 17 2006, 02:01AM
Location: Esbjerg Denmark
Posts: 720
Yes. you are correct.
standard diodes are fine.
Back to top
Plasmaniac
Thu May 25 2006, 06:47PM
Plasmaniac Registered Member #206 Joined: Sat Feb 18 2006, 03:17PM
Location:
Posts: 72
I used 1n5408s (I know this was stupid). It seems like the kickback current exceeded 200A and blew the diodes, so I had nearly no load when I triggered the puk the second time. I also never thought that <20J can blow a puk...
Back to top
Self Defenestrate
Thu May 25 2006, 10:00PM
Self Defenestrate Registered Member #87 Joined: Thu Feb 09 2006, 01:36PM
Location: San Jose
Posts: 191
For protection diodes, I use a semikron bridge rectifier, rectifier modules tend to have some good surge ratings. Something to keep an eye out for.
Back to top
Eric
Thu May 25 2006, 10:46PM
Eric Registered Member #69 Joined: Thu Feb 09 2006, 07:42AM
Location:
Posts: 116
If you are not going to be using electrolytic caps you ought not to need a protection diode. Seems like these are often a major point of failure since they typically have a lower peak current handling ability than the SCR. You can always protect the SCR with a snubber and perhaps a TVS to absorb any turn-off transient.

As far as the SCR goes, sounds like a winner in terms of current handling ability. If ITSM is 10KA then you can probably do more than twice that for short duration pulses (~1ms). One thing to look at is the turn on time, max dI/dt, etc. to see how it will switch the kind of fast pulse you'd be generating. If you exceed that, it could fail. Got a datasheet?
Back to top
Quantum Singularity
Fri May 26 2006, 12:09AM
Quantum Singularity Registered Member #158 Joined: Sun Feb 12 2006, 09:53PM
Location: Central Ohio
Posts: 282
Eric - I will be using the SCR's for electrolytic banks. I dont think it would be feasable for me to try solid state switching on my maxwells.

Thanks everyone for the opinions. Unfortunately I am shying away from that particular SCR module. I have found some smaller and cheaper ones rated nearly as high. And no, there was no datasheet provided nor part #'s so other than the given info the rest might be a mystery. If anyone is interested its on ebay at http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=7622706878&ssPageName=STRK:MEWA:IT
The opening bid is $50 US. But the thing just looks like a monster, check it out. I will probably not bid so its open game.

The other ones I am currently looking at are Eupec modules for $10 each on ebay (please dont bid against me though please suprised ). I am waiting on the guy to get back with me though, he is supposed to have 3 available. And there are very detailed specsheet on Mousers site here

But the important specs are:
1200V
6700A Itsm
200A/us dit/dt
500V/us critical rise time for off-state voltage
250mA max Igt
2.2V max Vgt

at 6700amps peak and with 3 units in parallel this may be more robust than the monster above, plus smaller and cheaper. This is a brick(?) style unit. And again, for these I have vary detailed specsheet available.
Back to top

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

Go to:

Powered by e107 Forum System
 
Legal Information
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.