ABB ACQ810 - Motor Control; Constant Speeds; Critical Speeds; Speed Controller Tuning

68 Program features
Motor control
 Constant speeds
It is possible to predefine up to 7 constant speeds. Constant speeds can be activated,
for example, through digital inputs. Constant speeds override the speed reference.
Settings
Parameter group 26 Constant speeds (page 185).
 Critical speeds
A Critical speeds function is available for applications where it is necessary to avoid
certain motor speeds or speed ranges because of, for example, mechanical
resonance problems.
Settings
Parameter group 25 Critical speed (page 184).
 Speed controller tuning
The speed controller of the drive can be automatically adjusted using the autotune
function (parameter 23.20 PI tune mode). Autotuning is based on the load and inertia
of the motor and the machine. It is, however, also possible to manually adjust the
controller gain, integration time and derivation time.
Autotuning can be performed in four different ways depending on the setting of
parameter 23.20 PI tune mode. The selections Smooth, Middle and Tight define how
the drive torque reference should react to a speed reference step after tuning. The
selection Smooth will produce a slow response; Tight will produce a fast response.
The selection User allows customized control sensitivity adjustment through
parameters 23.21 Tune bandwidth and 23.22 Tune damping. Detailed tuning status
information is provided by parameter 06.03 Speed ctrl stat. If the autotuning routine
fails, the AUTOTUNE FAILED alarm will occur for approximately 15 seconds. If a stop
command is given to the drive during the autotuning, the routine is aborted.
The prerequisites for performing the autotune routine are:
• The ID run has been successfully completed
• Speed, torque, current and acceleration limits (parameter groups 20 Limits and 22
Speed ref ramp) are set
• Speed feedback filtering, speed error filtering and zero speed are set (parameter
groups 19 Speed calculation and 23 Speed ctrl)
• The drive is stopped.
The results of the autotune routine are automatically transferred into parameters
• 23.01 Proport gain (proportional gain of the speed controller)