Peter C. Wallace wrote:
> It looks like the integral term has some funny problems in the pid comp.
>
> The symptom is that when the integral term causes the output to saturate, and 
> there is no integral limit or the integral limit is > MaxOutput/Igain it 
> never recovers, and ends up driving in one direction regardless of the error, 
> This seems to be broken in the part of the code that prevents integral wind-up
> this code prevents integral wind-up but also prevents recovery if the output 
> saturates (because its stops calculating the integral term in when 
> in saturation an therefor the integral term that cause the saturation is 
> "latched")
>
>   
Good detective work!  I have never liked the way EMC's I term worked, 
form the very beginning.
The original one had no "horizon" so error from hours ago could still 
influence the output.
The new one was supposed to work, but I think your discovery exactly 
matches what I have seen.

Jon

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