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Discussion Starter #1
sorry if this has been said already, but i know its possible to build yourself a 144v 500amp controller. but would it be possible to build yourself something like 1500A 230v dc controller? i know it sounds crazy but are the parts available to get?

thanks
 

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Hi. I'll say 'yes' if you promise not to ask 'how'. There are commercial controllers that can do that and more so the technology is available. But at that current level, component/circuit layout becomes a serious concern, not to mention heat removal and power I/O handling. A current loop that could be "lived with" at 500A, it might be a showstopper at 1500A, for example.

Hopefully you're also looking at the cells that will supply that amount of current - not easily done - and the motor rating to handle it on the other end.

What kind of rocket and/or welder are you building?

JR
 

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It's quite possible. If you get the plans and make yourself an "Open ReVolt" controller you can customise the power stage to be as big (or as small) as you like, including teaming masses of high-voltage IGBTs to make the controller as insane as you'd like.

Of course, storing and accessing that much power would be another thing entirely...
 

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Discussion Starter #4
ok, so its pretty much the same, but beefier" parts that supply power...ect

i i ever build it it would be liquid cooled or sure
 

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Discussion Starter #5
so ill be studying the forum on how to build a controller, and i should be starting to build this thing in a few weeks
 

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Paul is building an open source 1000 amp controller....I would support that effert and learn first if this is your first time doing something like this...
 

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OMT you got one little hurdle to get over. What size electrical service do you have at the site with this monster? A typical single phase 240/120 200 amp residential service is not going to cut it. You would need a 3 phase 208/120 300 amp service using a 3 phase rectifier to pull it off providing everything else is off in the home. If that were not enough headaches all your 240 appliances would have to have their taps changed to 208, or replaced if they cannot operate at 208. Other way is a 3 phase 480/277 service then install a single phase transformer for your 240/120 stuff in the home.

Just a little headache. :D
 

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I'd talk to jackbauer on here. He has driven some very high power igbts with the basic open revolt control board, and it's made to drive mosfets. To do it right you would probably want a driver board that is actually made for igbts. I think the regular old pwm signal could drive an HCPL-4506 optocoupler, which could drive multiple drivers. For each giant igbt, I would give each driver its own isolated supply too, and drive it with like -8v off and 15v on or so. adamj12b made a driver board for this. he's got a really high power controller in the works.
 

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Discussion Starter #10
thanks for the help guys, im in sschool right now, and am pretty busy with other things, but when i get some time ill finalize what i want out of the controller, and talk to people that have built them before. ill need asmuch help as i can, as i am not experienced in making circuits.
 

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I started building the open revolt controller, and at the same time while waiting for the parts I did this one with IGBTs, i tested it today on a small motor but tomorrow will be the better test with a motor for my bike that is in the works.

http://billsevaccent.blogspot.com/search?updated-min=2010-01-01T00:00:00-08:00&updated-max=2011-01-01T00:00:00-08:00&max-results=50

im not finished with the open revolt controll board, Im still waiting for the current transducer and a couple of other components but I built a driver circuit to play with it today.this controller and the open revolt will both be water cooled, you can see the cooling plate in the pictures. ummm i mean test it today
 

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yes it does have freewheel diodes, i got the idea from your posts on ecomodder, while reserching the open revolt controller.
Well this isn't going to end well... Those IGBT modules only have two terminals on top, so they must be single IGBTs. For a motor controller you need modules with three terminals, either two IGBTs in series (half-bridge), or an IGBT and freewheeling diode in series (chopper). You can't use the anti-parallel diode across the IGBT in a single IGBT module as the freewheeling diode.
 

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I was going to post this earlier, but got sidetracked. Here it is.

quote=billhac;207667]yes it does have freewheel diodes, i got the idea from your posts on ecomodder, while reserching the open revolt controller.[/quote]


Im looking at the pictures and im trying to make out what IGBT's you used. All i can see for the part number is "MG500Q....". With some searching I found the MG500Q1US1. Is this the correct module? If it is, the parasitic diode that is across the switch will not perform the function you are looking for. You need a diode that is connected from M- to B+. The parasitic diode in the IGBT is connected from B- to B+.

I was also trying to figure out what capacitors you are using. I cannot see any info except for 200V.

-Adam
 

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...the parasitic diode that is across the switch will not perform the function you are looking for...
Couple of things to clarify here, Adam. The anti-parallel diode across IGBTs is a totally separate device, not intrinsic to the structure as it is in MOSFETs. In both devices, though, the anti-parallel diode is eminently suited to being used as a freewheeling diode, it just needs to be in the proper location, is all ;)

Yeah, those capacitors look really shaky. And the high inductance pathway between them and the modules isn't good, either, but until the circuit gets sorted out it's still a bit premature to worry about "details" like these....
 

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Couple of things to clarify here, Adam. The anti-parallel diode across IGBTs is a totally separate device, not intrinsic to the structure as it is in MOSFETs. In both devices, though, the anti-parallel diode is eminently suited to being used as a freewheeling diode, it just needs to be in the proper location, is all ;)
Hi Jeffery,

I get it. My mistake. In the IGBT the diode is designed there, MOSFETS there left over from manufacturing process. Right?

-Adam
 

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Well this isn't going to end well... Those IGBT modules only have two terminals on top, so they must be single IGBTs. For a motor controller you need modules with three terminals, either two IGBTs in series (half-bridge), or an IGBT and freewheeling diode in series (chopper). You can't use the anti-parallel diode across the IGBT in a single IGBT module as the freewheeling diode.
i have semikron diodes coming for it.
 

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...In the IGBT the diode is designed there, MOSFETS there left over from manufacturing process. Right?
Yep - the intrinsic diode in the MOSFET is formed when the base and emitter of the parasitic bipolar transistor are shorted together. Diodes formed in this way (ie - collector-base) are usually very slow, so doping is required to make them at least a nominally good match for the potential speed of a MOSFET, but they do alright most of the time.
 

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Couple of things to clarify here, Adam. The anti-parallel diode across IGBTs is a totally separate device, not intrinsic to the structure as it is in MOSFETs. In both devices, though, the anti-parallel diode is eminently suited to being used as a freewheeling diode, it just needs to be in the proper location, is all ;)

Yeah, those capacitors look really shaky. And the high inductance pathway between them and the modules isn't good, either, but until the circuit gets sorted out it's still a bit premature to worry about "details" like these....
every thing looks shaky to you,the caps are the same ones for the open revolt, only 1000uf,i dont claim to be a pro it is just a hobby, why not say good first try, or something positive.
 
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