Speed Pid Control; The Following Parameters Are Relevant For The Speed Control - Danfoss VLT AutomationDrive FC 300 Design Manual

FC 300 Design Guide

Speed PID Control

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The table shows the control configurations where the Speed Control is active. To see where the
Speed Control is active, please refer to the section about the Control Structure.
Par. 1-00
Configuration Mode
[0] Speed open loop
[1] Speed
closed-loop
[2] Torque
[3] Process
open-loop
Note: "N.A." means that the specific mode is not available at all. "Not Active" means that the
specific mode is available but the Speed Control is not active in that mode.
Note: The Speed Control PID will work under the default parameter setting, but tuning the parameters
is highly recommended to optimize the motor control performance. The two Flux motor control
principles are specially dependent on proper tuning to yield their full potential.

The following parameters are relevant for the Speed Control:

Parameter
Speed PID Feedback Resource
Par. 7-00
Speed PID Proportional Gain
Par. 7-02
Speed PID Integral Time Par.
7-03
Speed PID Differentiation Time
Par. 7-04
Speed PID Diff. Gain Limit Par.
7-05
Speed PID Lowpass Filter Time
Par. 7-06
Introduction to FC 300
Par. 1-01 Motor Control Principle
U/f VVCplus
Not Active Not Active
N.A. ACTIVE
N.A. N.A.
N.A. Not Active
Description of function
Select from which resource (i.e. analog or pulse input) the Speed PID should get
its feedback
The higher the value, the quicker the control. However, too high a value may
lead to oscillations.
Eliminates steady state speed error. Lower value means quick reaction. However,
too low a value may lead to oscillations.
Provides a gain proportional to the rate of change of the feedback. A setting of
zero disables the differentiator.
If there are quick changes in reference or feedback in a given application - which
means that the error changes swiftly - the differentiator may soon become too
dominant. This is because it reacts to changes in the error. The quicker the error
changes, the stronger the differentiator gain is. The differentiator gain can thus be
limited to allow setting of the reasonable differentiation time for slow changes and
a suitably quick gain for quick changes.
A low-pass filter that dampens oscillations on the feedback signal and improves
steady state performance. However, too large a filter time will deteriorate the
dynamic performance of the Speed PID control.
MG.33.B3.22 - VLT is a registered Danfoss trademark
Flux sensorless Flux w motor feedb
ACTIVE N.A.
N.A. ACTIVE
N.A. Not Active
ACTIVE ACTIVE
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