Rockwell Automation Publication 750-AT006D-EN-P - January 2022
37
Chapter 2 Product Features
Internal signals and their descriptions are summarized in
. These signals are operational even when adaptive tuning is disabled.
Output parameters and their descriptions are summarized in
10:2119
[AdptTuneMinScale]
Adaptive Tuning Gain
Scaling Factor Minimum
The adaptive tuning Gain Stabilization function incrementally decreases the gain scaling factor to
stabilize the system if necessary or until the gain scaling factor equals this low limit.
10:2134
[GnStab TorqueLim]
Gain Stabilization Torque
Limit
Enter the gain stabilization torque limit. Gain stabilization uses this value to determine stability margin
and whether to decrease parameter 10:2121 [AdptTune GnScale]. Increasing this value decreases the
stability margin.
10:2135
[GnOpt TorqueLim]
Gain Optimization
Torque Limit
Enter the gain optimization torque limit. Gain optimization uses this value to determine stability
margin and whether or not to increase 10:2121 [AdptTune GnScale]. Increasing this value allows gain
optimization to increase gains to further increase P2121 [AdptTune GnScale]. This value should be
smaller than 10:2134 [GnStab TorqueLim].
10:2136
[GnOpt Scale Inc]
Gain Optimization
Scale Increment
Enter the gain optimization gain scale step increment. This value is added to parameter 10:2121
[AdptTune GnScale] each time gain optimization increases it.
10:2137
[GnOpt Error Type]
Gain Optimization
Error Type
Select the type of error measured and used
by adaptive tuning during gain
optimization. Position error is measured in
Position mode and velocity error is
measured in Velocity mode.
• 'Peak' (0) - Measures peak position or velocity error to
compare to error threshold for gain optimization.
• 'Steady State' (1) - Measures steady state position or
velocity error to compare to error threshold for gain
optimization.
10:2139
[GnOptPosErrThrsh]
Gain Optimization Position
Error Threshold
Enter the position error threshold used by gain optimization when in Position mode. When this value is
zero, gain optimization increases parameter 10:2121 [AdptTune GnScale] in each control loop by
parameter 10:2136 [GnOpt Scale Inc] regardless of measured error until parameter 10:2130
[AdptTuneStabMag] reaches between the 10:2135 [GnOpt TorqueLim] and 10:2134 [GnStab TorqueLim]
lines, as shown in
10:2140
[GnOptVelErrThrsh]
Gain Optimization Velocity
Error Threshold
Enter the velocity error threshold used by gain optimization when in Velocity mode. When this value is
zero, gain optimization increases parameter 10:2121 [AdptTune GnScale] in each control loop by
parameter 10:2136 [GnOpt Scale Inc] regardless of measured error until parameter 10:2130
[AdptTuneStabMag] reaches between the 10:2135 [GnOpt TorqueLim] and 10:2134 [GnStab TorqueLim]
lines, as shown in
10:2141
[GnOptSclHiLim]
Gain Optimization Scale
High Limit
Enter the gain scale high limit for gain optimization. Gain optimization will not increase parameter
10:2121 [AdptTune GnScale] beyond this limit.
10:2142
[GnOpt Time]
Gain Optimization Time
Enter a time that Gain Optimization will be active until it automatically switches to Gain Stabilization.
When this parameter is set to zero, Gain Optimization will remain active all the time.
Table 12 - Adaptive Tuning Internal Signals
Parameter No.
Parameter Name
Description
10:2121
[AdptTune GnScale]
Adaptive Tuning Gain
Scaling Factor
Displays the adaptive tuning Gain Scale Factor.
• The adaptive tuning Gain Stabilization function decreases this value by incrementally multiplying a factor
of 0.75x to scale position loop, velocity loop, and load observer gains to stabilize the system if necessary.
The instability is caused from resonances that are not already suppressed by filters or the instability is
caused by filter bandwidths that are too close to the closed loop bandwidth.
• The adaptive tuning Gain Optimization function increases this value by incrementally adding
10:2136 [GnOpt Scale Inc] to scale position loop, velocity loop, and load observer gains to improve
performance while remaining stable.
10:2123
[Trq NF Freq Est]
Torque Notch Filter
Frequency Estimate
Displays the center frequency estimate of the current mechanical resonance that is identified by adaptive
tuning.
• If multiple resonances exist with magnitudes above the threshold, then the one with the largest
magnitude is selected.
• If two resonances with equal magnitude exist, then the one with the lowest center frequency is selected.
10:2124
[Trq NF Mag Est]
Torque Notch Filter
Magnitude Estimate
Displays the magnitude estimate of the current resonance that is identified by adaptive tuning.
• Adaptive tuning identifies resonances and estimates their magnitudes and widths.
10:2125
[Trq NF Wdth Est]
Torque Notch Filter
Width Estimate
Displays the width estimate of the current resonance that is identified by adaptive tuning.
• Adaptive tuning identifies resonances and estimates their magnitudes and widths.
10:2129
[AdptTuneStabFreq]
Adaptive Tuning
Stability Frequency
Displays the center frequency estimate of a resonance that reflects stability margin.
10:2130
[AdptTuneStabMag]
Adaptive Tuning
Stability Magnitude
Displays the magnitude estimate of a resonance that reflects stability margin.
10:2138
[GnOpt Error Max]
Gain Optimization
Error Maximum
Displays the maximum velocity or position error used in gain optimization, in error units.
Table 11 - Adaptive Tuning Settings (Continued)
Parameter No.
Parameter Name
Description