User Manual V 1-4.XX User guide

B-18 Control Block Diagrams
Using the Kf Gain
In addition to the Kp and Ki gains, the speed PI regulator also uses a
Kf gain. The Kf gain affects the speed overshoot in response to a step
change in speed reference. You can adjust the Kf gain parameter at
any time, independent from the proportional and integral gains
without affecting the stability of the system.
Chapter 13, Understanding the Auto-tuning Procedure, provides
more information about the Kf gain.
Scaling the Speed Pi Regulator Gains
Kf Speed Loop (parameter 160), Kp Speed Loop (parameter 159), and
Ki Speed Loop (parameter 158) are available for scaling the gains.
The scaling used for each of these parameters is in eighths (8 = 1.0).
Using the Error Filter Bandwidth
Error Filtr BW (parameter 162) provides a low-pass filter for
applications that require more noise filtering. When using Error Filtr
BW, keep the value of the parameter between 3 and 5 times greater
than the value of Spd Desired BW (parameter 161), which represents
the bandwidth of the speed loop.
Additional information about Error Filtr BW is located in Chapter 13,
Understanding the Auto-tuning Procedure.
Adjusting the Motor Speed with Changes in Load (Droop
Gain)
For some applications, you may want the motor speed to droop with
an increase in load. In these cases, you can use Droop Percent
(parameter 46) to specify the percent of base speed that the speed
reference is reduced when at full load torque.
file:
Control
group:
Speed Regulator