Quote:
Originally Posted by MPaulHolmes
I just got done with a 1500 mile drive with my 1 year old in the back seat from Olympia to Maricopa. Boy that wasn't fun! We even ran over the big fat middle section of a dead deer. Rain and 60 in Washington, sun and 105 down here. haha.
You can definitely get multiple gate drivers to work. Ian Hooper (who is the reason I started working on controllers for cars in the first place) has made reliable controllers using up to 6 drivers and 12 mosfets. He didn't tie the outputs (pwm) of the drivers together though. He just had 2 mosfets per driver on a separate little driver board. Maybe the blowup was caused by something else? Those drivers have like a 15nS response time. Do you know at approximately what conditions (current of motor, current from batteries, pwm duty) the controller blew up?
mora, I'll try to find the .hex file. Man, I'm awful with knowing which version is which, and not keeping old versions. I tried SVN once, and wanted to stab myself in the eyeball with a fork afterwards.
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Thanks Paul.
When it blew up I was booting it from a standing start, I dont know what current was being pulled, I do know that during my short runs at quite a high accelleration in the road outside my house I was pulling 400A as indicated by the 75ma shunt/ammeter. Batteries were up at 153v and are new,
I have redesigned my power amp board with just one 4451 driver (TO220 package) and ten 10ohm resistors into ten 75A 600V IGBT's. I was using ten 6A drivers into ten 130A 200v MOSFETs, same ones that you used.
I think when this board goes live I will set up a video camera pointed at the meters so I can see what happens.
I dont know how to safely check the current limiting without booting it and seeing what happens. I have calculated the setting (500A) using the online datasheet for the Lem HTFS I am using. I will set it at 300A next time.
I could not work out from your cct diagram exactly how the current limiting was done. It seemed to me that it inhibited the PWM drive to the fet drivers and returned it as soon as the current dropped. There is a line from the sensor that goes to the processor, but I did not know if it is an input or output.
Adam said that it operates very quickly and sharply so I think I worked out correctly. I thought the juddering was the current limiting working but possibly just the FETS blowing as it was quite slow.
