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Originally Posted by Kevin Sevcik
I've now deciphered the current sampling strategy employed by the Jaguars...
current... [is] sampled every PWM cycle, with an offset to put the sample in the middle of the PWM pulse...
Current ... is put through a 16x super-sampling, 8-point moving average filter.
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Nice work! Thank you for this information!
So the Jag firmware is doing both: digital filtering
and phase-locking the sample to the bridge switching.
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So you end up with something like a 976Hz update rate for the current, but a bandwidth of something like 122Hz or less.
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Well, the 976Hz makes sense, since the PID in the Jags is updated at about the same rate.
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Of the instantaneous value in the middle of the PWM pulse, lest we forget.
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Right. Now the question now becomes: what is the relationship between this metric, RMS, and algebraic average.