Assuming you can slap them around hard enough you may want to look into SOT227 packaged FETs and solid copper bus bars. You can see Storm II has an ESC built of them here: http://www.teamstorm.com/storm2/speed.htm.
Considering the thermal problems of ESCs only happens after your first DIY ESC.
TMHWK used the 36V 1000W version with succes.
Why, untill recently it was reasonably simple to find a set of Bosches.
And there ain't that many heavies build in the last years.
See, that was my thinking but I never like to assume that's the case :L Could be useful if they turn out to be a good drive motor given the various new heavies being built..There must be a reason for their lack of widespread use in heavyweights other than people not having discovered them yet
And those ESCs look very nice! Thermal issues were always considered.. I just hadn't realised the quantities of heat that needed to be handled!
Rebuild supernova. Enough said í ½í¸ƒ
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I have built an ESC for Beta's weapon (Etek run off 14s lipo-60v) using these 200A bolt on terminal packages.
http://uk.farnell.com/ixys-semicondu...27b/dp/1427322
IXYS also do the same package with a higher rating also.
Damn! That is insane! Reminds me of the ESC's that were built for Tornado back in the day... but even bigger!Originally Posted by grant_ploughbot
Grant, given Beta never aired on BB does that leave it open for a UK competition or is it still tied to Battlebots?
It can compete on the UK scene where not televised as with all the UK machines who attended. They have been very good in being as flexible as possible for us. I will probably only bring beta out every now and then for testing, and it would need to be on a reduced power on a non magnetic floor. It may also punch holes through the UK arena floors so that will need to be tested.
I have since done a lot of testing with this ESC, which is taking 1200A for a short period, then 500A co Tunisia after that. They don't get warm so far.
Those are some beautiful ESCs, however I'm looking to produce a slightly lower end PCB based solution, something to handle Bosch 750s and the like. I really need to research the layout of more controllers; anyone got pics of the insides of one of the lower end Wottys or something similar? My aim is to get it all fitting on at most a double sided 10cm x 10cm pcb, as then it can be printed cheaply in china. Hopefully further research will show whether that's possible or not..
The Wotty uses smaller package 3 legged Fets rated to about 350A each, however due to the package size they're more like 80A each I would expect (hence he uses a number of them!).
My setup at present uses large surface mount 340A fets with a package rating of about 200A... The 320A rating in this case just means lower on resistance so less heat, which helps. My fet drivers only supply a measly 125mA to the gates though, so i'll be upping that to the proper 1.2A H bridge driver chips that most other people seem to use.
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