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Old 07-21-2009, 06:44 PM   #6 (permalink)
Join Date: Feb 2009
Location: phx
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Interesting! I'd definitely like to try some sort of PI loop - just curious, why no derivative term?

I like the third option too - It sounds like a way to have control of current at low speeds; i'd probably set it up for half the pedal range or something. Maybe this middle term would be:

else if (current/2 > throttlePos) {

with 144V input and the Curtis, I'd rarely press the pedal more than 65% or so, meaning that my max required duty cycle is about .65. I'd cruise around 50%, and hill climb at 65%. (i'm basing these numbers off of the ratio of battery amps to motor amps). Occasionally, I'd punch it to merge or something, but that is rare.

I really like the idea of the PI loop to control current though - seems like it would truly make the hardware overcurrent feature more of a a protection feature than an integral part of the controller operation. I'm toying in my mind how to integrate the two... haven't figured it out yet.
ReVolt AZ testing thread:
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