With very low Kp, integrator can get stuck below setpoint when antiwindup equals p
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elcojacobs commented
When the proportional gain is very low (which could be used with a PID driving another setpoint), it is possible to not reach setpoint in steady state.
This is due to a combination of events.
This can only happen if the actuator is not reaching setpoint, by margin a
. This margin is multiplied by the anti-windup gain of 3. If p
equals 3a
, we are stuck.
The integrator is increased with p every cycle.
The antiwindup is (pid result - achieved output) * 3
.
When these two cancel each other out, the integrator is stuck in a steady state value, without the error being zero.
elcojacobs commented
Should be fixed in develop