Functions That Improve Response - YASKAWA SGM Series User Manual

Application

5.9.3 Functions that Improve Response

5.9.3 Functions that Improve Response
5
D Cable Colors and Monitor Signals
Cable Color
Red
White
Black (2 wires)
The following functions are provided to improve response.
D Mode switching
D Feed-forward control
D Bias
These functions will not necessarily improve characteristics, and they can even have the oppo-
site effect. Be sure to observe the precautions given below, and monitor the actual response
of the characteristics while making adjustments.
J Mode Switching
Mode switching is used to improve transient characteristics if the torque reference saturates
during acceleration and deceleration. In other words, mode switching is a function that auto-
matically switches the speed control mode inside the SERVOPACK from PI (proportional/in-
tegral) to P (proportional) control above a certain setting.
J Feed-forward Control
Feed-forward control generally shortens positioning time, but has no effect on systems where
the position loop gain is at its maximum. Adjust the amount of feed-forward control using
Cn-001D as outlined below.
1. Adjust the speed and position loop.
2. Gradually increase the amount of feed-forward control set in Cn-001D until the position-
ing complete status (PSET) is output as quickly possible.
Make sure during adjustment that the position complete status (PSET) is not intermittent (re-
peatedly turning ON and OFF) and that the speed is not overshoot. Setting the amount of feed-
forward control too high will cause a intermittent positioning complete status as well as speed
overshooting.
A primary lag filter may be added to the feed-forward line to improve characteristics when the
positioning complete signal is intermittent or when speed overshooting occurs due to excessive
feed-forward control.
J Bias Control
When the number of pulses in the error counter exceeds the positioning complete width
(Cn-001B), bias (Cn-001C) is added to the error counter output (speed reference) until the
Signal Name
VTG-M Speed monitor (0.5 V, 1,000 min
TRQ-M Torque monitor (0.5 V, 100% torque)
GND GND
5 -24
Description
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