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Old 05-07-2018, 07:50 PM   #3231 (permalink)
MPaulHolmes
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Holy cow I missed a lot! Fortunately, I am now unemployed, and can check here more often. haha.

For thingstodo:
You have to pretend that you are from the matrix... Remember how they see the random numbers and see all sorts of events happening? 200010220 20202020 "oh no! Neo is fighting the bad guys"

When you do run-pi-test2, what you want to see is convergence toward 0. It should start at around 512, and quickly fall to 0. It won't really fall to exactly zero. So, something like this when you type run-pi-test2:
512, 512, 460, 440, 430, ..., 100, 50, -50, 60, 0, -40, .....

The rate of convergence depends on the specific motor. For big motors it usually converges really fast (like in 10 or 20 iterations). For small ones maybe in 40 or 50 or something iterations? I've seen it as slow as 90 before.

If it converges to zero, (but bounces around zero), you are good. If it goes too negative, and then comes back, then you need to reduce your Kp and Ki. It's a little too agressive and wild. Also, make sure Kp is around 60*Ki, whatever you are using for Ki.

Reversing polarity of the B+ and b- could be very bad. That's a dead short across 2 diodes inside the IGBTs. Now, those big diodes can handle 600 amp each, and you have 3, so that's 1800amp that the IGBTs could handle. I bet the 58v battery pack wasn't able to deliver that. Was there a fuse that could have blown so that the precharge can still do its thing, but the main contactor can't?

The software is very similar to what it was before. You sholdn'thave to use different numbers for your motor.

wootwootman: don't bother with run-pi-test. Just do run-pi-test2. Human eyes on the data is better than the sad amount of intelligence I tried to bestow upon the little microcontroller, which is basically a computer from 1975.

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Last edited by MPaulHolmes; 05-07-2018 at 08:09 PM..
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