Parker Aries AR-08AE - Page 142

Chapter 6 Command Reference - 125 -
accuracy is achieved with proportional gain (SGP), then the integral gain
(SGI) need not be used.
If the integral gain is set too high relative to the other gains, the system may
become oscillatory or unstable. The integral gain can also cause excessive
position overshoot and oscillation if an appreciable position error has
persisted long enough during the transient period (time taken to reach the
position setpoint); this effect can be reduced by using the SGILIM command
to limit the integral term windup.
SGILIM
Integral Windup Limit
Type
Tuning
Product Rev
Syntax
<a_>SGILIM<i>
Aries 2.0
Units
i = Limit value
Range
Ø to 32767
Default
1
Response
SGILIM: <*>1
See Also
SGI, SGP, SGV
This command is only valid in DMODE4 (velocity mode) and DMODE6 or 7
(position mode). If integral control (SGI) is used and an appreciable position
error has persisted long enough during the transient period (time taken to
reach the setpoint), the control signal generated by the integral action can
end up too high and saturate to the maximum level of the drive's analog
control signal output. This phenomenon is called integrator windup
After windup occurs, it will take a while before the integrator output returns to
a level within the limit of the controller's output. Such a delay causes
excessive position overshoot and oscillation. Therefore, the integral windup
limit (SGILIM) command is provided for you to set the absolute limit of the
integral and, in essence, turn off the integral action as soon as it reaches the
limit; thus, position overshoot and oscillation can be reduced.
SGP
Servo Gain Proportional
Type
Tuning
Product Rev
Syntax
<a_>SGP<i>
Aries 2.0
Units
i = gain value
Range
Ø.ØØ to 1Ø0Ø.ØØ
Default
Ø.6Ø
Response
SGP: <*>Ø.6Ø
See Also
SGILIM, SGI, SGV, PGAIN
This command is only valid in DMODE4 (velocity mode) and DMODE6 or 7
(position mode). SGP allows you to set the gain of the proportional term in the
servo control algorithm. The output of the proportional term is proportional to
the difference between the commanded position and the actual position read
from the feedback device. The primary function of the proportional term is to
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