Appendix C: Tuning Your System
87
Figure C-5. Insufficient Integral Gain
Note that the integral gain may be inactive during motion is the axis is configured for an Integral
mode of "Only Standing". To close the following error during motion, use the feed-forward filter
terms. Also note that the integration limit affects the performance of the integral gain.
C.2.4 Velocity Feed Forward (K
v
)
The velocity feed-forward term is very important when used with velocity controlled servos or
closed-loop step motors. As the speed of a system increases the position error generally
increases and therefore a higher output voltage or pulse rate is needed. The Velocity Feed-
Forward term reduces the following error by increasing the controller output voltage at high
speed. If the Velocity Feed-Forward term is too large the motor will try to travel ahead of the
command position.
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com