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Old 04-13-2009, 12:17 AM   #899 (permalink)
MPaulHolmes's Avatar
Join Date: Feb 2008
Location: Maricopa, AZ (sort of. Actually outside of town)
Posts: 3,832

Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000
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I've got lots of progress to report on the control board and the driver board. I also ordered the part (I ordered 3 actually! ya!) that will allow for powering the contactor from inside the controller! I had one idea how to do this, and my little guardian angel emailed me showing me a really really awesome way to do it! The micro-controller now decides when the contactor shall turn on and off!

Like in "War Games", we took the human out of the loop!

QUOTE THE GENERAL: Gentlemen, we've been having men down in them silos since before any of you were watching howdee doodee! I don't know about you, but I sleep pretty well knowing those boys are down there!

Hmm... How about the pre-charge resistor? Heck! Let's take that part over too! Maybe we should even have the dang pre-charge resistor inside the controller? I don't know! That would be cool! That would cut down on wires to plug into the controller. Less human error.

You turn the car on and go! You turn the car off, and it's off! I like it!

I ordered some TINNIT Bright Tin Plate stuff. It puts a tin plating on copper! Now our copper bus bars can be nice and tinned and shiny! immune to corrosion!

Hmm... I've been working on the layout for the mosfet driver board (well, the "board" is only 0.8"x8" haha!). I'm going to have to surface mount the "through hole" parts. just a few. NO biggie! Then, the mosfet driver board is going to communicate with the control board by LIGHT! No electrical interference will be able to pass through! OPTO-ISOLATION! It's so dang awesome, I can hardly stand it!

I also am adding a zener diode (I never knew what those really were until today. Don't tell anyone! It's a secret. I'm the "expert" hahahaha!) to not allow voltage spikes from gate to source. It will clamp the voltage from gate to source to no more than 20v. The voltage from gate to source can now freely rise to 20v, and then all of a sudden, BAM! NO MORE! HAHA! If even a small voltage spike of 30v hits the gate, it can destroy the mosfet. That could have been what happened last time. Now, that potential problem is eliminated!

I'm dramatically improving the ground connection between the mosfet driver and the power section. wire with LOTS of surface area. The control section will have it's own nice peaceful ground. That is going to dramatically smooth out the signals, like from the current sensor!

I hope those crystals from china get here soon, so I can run that sucker at 16 MHz.

Note: The improvements have all come from not me! haha! I love open source!
kits and boards
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