Rockwell Automation 21G PowerFlex 750-Series AC Drives Programming Manual - Manual (Page 131)

Rockwell Automation Publication 750-PM001J-EN-P - October 2014 131
Drive Port 0 Parameters Chapter 3
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No. Display Name
Full Name
Description Values
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UE CONTROL
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1560 FrctnComp Mode
Friction Compensation Mode
The friction compensation function calculates a feed forward torque signal P1567
[FrctnComp Out]. Friction compensation attempts to predict the motor torque required
to counteract load friction. The [FrctnComp Out] signal is summed with P685 [Selected
Trq Ref] and P686 [Torque Step]. This parameter enables the friction comp function and
selects possible sources of motor speed reference as follows:
“Disabled” (0) – Friction compensation function is disabled. P1567 [FrctnComp Out] is
zero so the motor torque reference is not affected.
“Int Ramp Ref” (1) – Friction compensation is enabled. The function is configured to use
the P595 [Filtered Spd Ref] summed with the position reference speed feed forward.
This is the typical setting that should be used for friction compensation on a stand-alone
drive when operating in position or speed mode.
“Ext Ramp Ref” (2) – Friction compensation is enabled. The function is configured to use
P700 [Ext Ramped Ref]. This setting is available for applications that supply a ramped
speed reference external to the drive.
“Speed Fdbk” (3) – Friction compensation is enabled. The function is configured to use
P640 [Filtered SpdFdbk]. A feedback device must be used – the speed feedback source
cannot be open loop feedback. This setting should be used when operating in torque
mode (min/max/torque).
Default:
Options: 0 = “Disabled”
0 = “Disabled”
1 = “Int Ramp Ref”
2 = “Ext Ramp Ref”
3 = “Speed Fdbk” RW 32-bit
Integer
1561 FrctnComp Trig
Friction Compensation Trigger
Sets the starting speed or trigger speed at which the friction compensation will be
applied when leaving the region near zero speed. The initial value for P1567 [FrctnComp
Out] at this speed will be P1564 [FrctnComp Stick]. Friction compensation will remain
active until the speed reference drops below the trigger speed minus P1562 [FrctnComp
Hyst] speed. At these low speeds, 1567 [FrctnComp Out] returns to zero.
Units:
Default:
Min/Max:
Hz
RPM
0.15
0.00 / 7.94 RW Real
1562 FrctnComp Hyst
Friction Compensation Hysteresis
This parameter together with 1561 [FrctnComp Trig] establishes a speed band around
zero speed. Friction compensation will be inactive (zero output) when the speed
reference is inside this band and active when outside. The points at which friction comp
becomes active and inactive differ by the amount of speed set in this parameter.
Units:
Default:
Min/Max:
Hz
RPM
0.06
0.00 / 7.94 RW Real
1563 FrctnComp Time
Friction Compensation Time
Sets the time interval that the stiction torque will be applied. When initially leaving the
zero speed region, the value in P1564 [FrctnComp Stick] will be used for the non-viscous
friction term. After the time period set in this parameter, the non-viscous friction will
ramp down to the value set in P1565 [FrctnComp Slip]. For the remainder of the time
that [FrctnComp Out] remains non-zero, the non-viscous friction will remain constant at
the value of [FrctnComp Slip].
Units:
Default:
Min/Max: mSec
6
0 / 18 RW 32-bit
Integer
1564 FrctnComp Stick
Friction Compensation Stiction
Sets the level for the stiction or static friction torque. This is the torque level required to
break away from zero speed. When initially leaving the zero speed region, this level will
be used for the non-viscous friction term. After the time period set in P1563 [FrctnComp
Time], the non-viscous friction will ramp down to the value set in P1565 [FrctnComp
Slip].
Units:
Default:
Min/Max: %
15.00
0.00 / 800.00 RW Real
755
755
755
755
755