INVT Goodrive350 Series Operation Manual page 142

Goodrive350 series high-performance multifunction VFD
Unwinding in speed mode
Unwinding in torque mode
5.5.20.2 Speed control
The detection feedback signal is needed in the closed-loop adjustment. PID calculation is carried out
according to the feedback signal for the motor speed regulation, linear speed and stable tension
control. If the tension rocker or floating roller is used for feedback, changing the set value (PID
reference) may change the actual tension, and at the same time, changing the mechanical
configuration such as the tension rocker or floating roller weight can also change the tension.
The control principle is as follows.
Linear speed
Tension reference
Tension feedback
Related modules:
(1) Linear speed input module: It is important for the calculation of the basic setting frequency
according to the linear speed and the calculation of roll diameter according to the linear speed.
(2) Real-time roll diameter calculation module: The calculation accuracy of roll diameter determines
the control performance. The roll diameter can be calculated according to the VFD output frequency
and the linear speed. In addition, it can also be calculated through the thickness or sensor. The linear
Calculate the frequency
according to the linear
speed
+
PID regulation
-
V
V
Basic reference frequency
Inching
frequency
-133-
Basic operation guidelines
Winding in torque mode
Winding in speed mode
Motor reference
+
frequency
+