ABB ACS 800 Series, Firmware Manual

Page: 184 / 340

Actual signals and parameters
184
23.04 ACC
COMPENSATION Defines the derivation time for acceleration/(deceleration) compensation. In
order to compensate inertia during acceleration a derivative of the reference is
added to the output of the speed controller. The principle of a derivative action
is described for parameter
23.03 .
Note: As a general rule, set this parameter to the value between 50 … 100% of
the sum of the mechanical time constants of the motor and the driven machine.
(The speed controller Autotune Run does this automatically, see parameter
23.06 .)
The figure below shows the speed responses when a high inertia load is
accelerated along a ramp.
0.00 … 999.98 s Derivation time 0 … 9999
23.05 SLIP GAIN Defines the slip gain for the motor slip compensation control. 100% means full
slip compensation; 0% means no slip compensation. The default value is
100%. Other values can be used if a static speed error is detected despite of
the full slip compensation.
Example: 1000 rpm constant speed reference is given to the drive. Despite of
the full slip compensation (SLIP GAIN = 100%), a manual tachometer
measurement from the motor axis gives a speed value of 998 rpm. The static
speed error is 1000 rpm - 998 rpm = 2 rpm. To compensate the error, the slip
gain should be increased. At the 106% gain value, no static speed error exists.
0.0 … 400.0% Slip gain value. 0 … 400
23.06 AUTOTUNE RUN Start automatic tuning of the speed controller. Instructions:
- Run the motor at a constant speed of 20 to 40% of the rated speed.
- Change the auto tuning parameter
23.06 to YES.
Note: The motor load must be connected to the motor.
NO No auto tuning. 0
YES Activates the speed controller auto tuning. Automatically reverts to NO. 65535
23.07 SP ACT FILT TIME Defines the time constant of the actual speed filter, that is time within the actual
speed has reached 63% of the nominal speed.
0...1000000 ms Time constant 1 = 1 ms
24 TORQUE CTRL Torque control variables.
Visible only if Master/Follower is Active (parameter
60.01 and parameter 99.04
= DTC.
24.01 TORQ RAMP UP Defines the torque reference ramp up time.
0.00 … 120.00 s Time for the reference to increase from zero to the nominal motor torque. 0 … 12000
24.02 TORQ RAMP DOWN Defines the torque reference ramp down time.
0.00 … 120.00 s
Time for the reference to decrease from the nominal motor torque to zero. 0 … 12000
Index Name/Selection Description FbEq
Speed reference
Actual speed
No Acceleration Compensation Acceleration Compensation
t t
% %