ABB ACS880 - Settings and Diagnostics; Speed Controller Autotune

1560
1380
690
540
1
2
3 4
22.87 (rpm)
(input of function)
22.01 (rpm)
(output of function)
Parameter 22.52 = 540 rpm
1
Parameter 22.53 = 690 rpm
2
Parameter 22.54 = 1380 rpm
3
Parameter 22.55 = 1560 rpm
4
Settings and diagnostics
Parameters:
•
Critical speeds: 22.51 Critical speed function…22.57 Critical speed 3 high (page 268)
•
Critical frequencies: 28.51 Critical frequency function…28.57 Critical frequency 3
high (page 310).
￭ Speed controller autotune
The speed controller of the drive can be automatically adjusted using the autotune
function. Autotuning is based on an estimation of the mechanical time constant (inertia)
of the motor and machine.
The autotune routine will run the motor through a series of acceleration/deceleration
cycles, the number of which can be adjusted by parameter 25.40. Higher values will
produce more accurate results, especially if the difference between initial and maximum
speeds is small.
The maximum torque reference used during autotuning will be the initial torque (ie.
torque when the routine is activated) plus 25.38, unless limited by the maximum torque
limit (parameter group 30 Limits) or the nominal motor torque (parameter group 99 Motor
data). The calculated maximum speed during the routine is the initial speed (ie. speed
when the routine is activated) + 25.39, unless limited by parameter 30.12 or 99.9.
The diagram below shows the behavior of speed and torque during the autotune routine.
In this example, 25.40 is set to 2.
Program features 49