Speed Controller Tuning; Settings - ABB ACS355 User Manual

142 Program features

Speed controller tuning

It is possible to manually adjust the controller gain, integration time and derivation
time, or let the drive perform a separate speed controller Autotune run (parameter
2305 AUTOTUNE
load and inertia of the motor and the machine. The figure below shows speed
responses at a speed reference step (typically, 1 to 20%).
n
(%)
n
N
A
A: Undercompensated
B: Normally tuned (autotuning)
C: Normally tuned (manually). Better dynamic performance than with B
The figure below is a simplified block diagram of the speed controller. The controller
output is the reference for the torque controller.
Speed
reference
Calculated actual speed
Note: The speed controller can be used in vector control, ie when
CTRL MODE setting is

Settings

Parameter groups
RUN). In Autotune run, the speed controller is tuned based on the
B
+ Error
-
value
VECTOR: SPEED
23 SPEED CONTROL
C D
Derivative
acceleration
Proportional,
integral
Derivative
or VECTOR: TORQ.
and 20 LIMITS
t
+
+
Torque
+
reference
9904 MOTOR