Let's say we're trying to control the speed of a motor to 20 revs/sec, and we know that our controller output for that speed is approximately 5. We currently have a Proportional controller to drive the motor to our 20 revs/sec setpoint, with some steady-state error.
If we included Feedforward but tuned it poorly, such that it outputs 2 instead of 5, will the following error still be less than it would have been with only the Proportional controller?
I would think that for Feedforward to reduce the steady-state error, the output would need to be able to drive the motor closer to the setpoint than the Proportional controller could do by itself (without unacceptable oscillations). Is this the case?