Fast, high power IGBT or MOSFET - Page 1
Forum section: electronics / beginners

author: Feanor
author_rank: Regular Contributor
timestamp: November 05, 2010, 01:40:15 am
content: I am looking for a fast, high power IGBT or MOSFET (400-600A and >1000V). The switching frequency of the application is around 60kHz, hence the device needs to be able to switch as fast as possible. Here is one that I found that would be quite suitable but very expensive from Farnell.http://au.element14.com/jsp/search/browse.jsp;jsessionid=AL1UCSYR3NZD4CWNBBSBFWI?N=0&Ntk=gensearch_001&Ntt=ff900r12&Ntx=mode+matchallpartial&suggestions=false&ref=globalsearch&_requestid=285559Here is the data sheethttp://www.infineon.com/dgdl/DS_FF900R12IE4_2_4.PDF?folderId=db3a304412b407950112b4095b0601e3&fileId=db3a30431f848401011febc3dd603eecThis device can handle 900A, which is over kill for my application, well rather it is overkill for my budget. The total switching time is 1.29us (worst case 125 degrees.) That is 15% of the switching cycle at 60kHz. Not good by any means but bearable for short periods of operation. My application could use as much current as possible.If you have not guessed the application is a large singing Tesla coil so the bigger the better as far as current rating goes.I have been trawling the suppliers pages looking for something with comparable or better switching times rated at about 400-600A. I have found a couple but nothing that really grabs me as being outstanding.If anyone knows of anything that can beat these switching times and still handle 400-600A then please point me in the right direction. Having a gate capacitance of under 50nF would be good too, and a anti parallel diode Trr as low as possible obviously. (sound like a kiddie asking Santa for a bike I know).

author: Simon
author_rank: Unknown
timestamp: November 05, 2010, 08:53:47 am
content: what about paralleling more than one mosfet ?, your asking for everything in one package thats got to be either unobtanium or very exspensive

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 05, 2010, 09:33:41 am
content: Devcies like this are always goinf to be expensive - surplus on ebay is your best bet to find something cheaper.

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 05, 2010, 09:58:47 am
content: i posted in another forum that i want to drive a nearly 1 ton boat with small 32HP engine, due tobudgeting/fundingreason. and then i realize that i have to be realistic, and start thinking on how to get the fund for a bigger engine... or else... settle for a smaller boat (load/spec)

author: Simon
author_rank: Unknown
timestamp: November 05, 2010, 10:01:24 am
content: well at those power levels choices do become tough and any old thing will not do

author: qno
author_rank: Frequent Contributor
timestamp: November 05, 2010, 10:13:43 am
content: Check this outhttp://www.fujielectric.com/device/semi/products/powerdevices/2pack.htmlRise time in an application 75 ns from 0 to 800 V and back.

author: Feanor
author_rank: Regular Contributor
timestamp: November 05, 2010, 12:57:39 pm
content: I checked out eBay. Surprisingly many of these things are going for surprisingly good prices, it is not the sort of item you associate with eBay at all. Thanks for the tip!Nice chart Fuji! Thumbs up to Fuji electric systems! That is all you really want to know right current and voltage!Paralleling devices is possible but leads to a whole host of potential problems. The measures needed to then avoid these problems could even end up increasing the cost! It also increases the chance of failure.Yes, I agree at some point reality sets in and you have to pay for what you get. Everything comes at a price.Thanks for the tips!