Danfoss VLT AutomationDrive FC 300 Programming Manual page 133

3 Parameter descriptions
7-31 Process PID Anti Windup
Option:
[0] Off
[1] * On
7-32 Process PID Start Speed
Range:
3
0 RPM* [0 - 6000 RPM]
7-33 Process PID Proportional Gain
Range:
0.01* [0.00 - 10.00 ]
7-34 Process PID Integral Time
Range:
10000.00 [0.01 - 10000.00 s]
s*
7-35 Process PID Differentiation Time
Range:
0.00 s* [0.00 - 10.00 s]
7-36 Process PID Diff. Gain Limit
Range:
5.0* [1.0 - 50.0 ]
7-38 Process PID Feed Forward Factor
Range:
0 %* [0 - 200 %]
7-39 On Reference Bandwidth
Range:
5 %* [0 - 200 %]
132
Function:
Ceases regulation of an error when the output frequency can no longer be adjusted.
Continues regulation of an error even when the output frequency cannot be increased or decreased.
Function:
Enter the motor speed to be attained as a start signal for commencement of PID control. When the
power is switched on, the frequency converter will commence ramping and then operate under
speed open loop control. Thereafter, when the Process PID start speed is reached, the frequency
converter will change over to Process PID control.
Function:
Enter the PID proportional gain. The proportional gain multiplies the error between the set point
and the feedback signal.
Function:
Enter the PID integral time. The integrator provides an increasing gain at a constant error between
the set point and the feedback signal. The integral time is the time needed by the integrator to reach
the same gain as the proportional gain.
Function:
Enter the PID differentiation time. The differentiator does not react to a constant error, but provides
a gain only when the error changes. The shorter the PID differentiation time, the stronger the gain
from the differentiator.
Function:
Enter a limit for the differentiator gain (DG). If there is no limit, the DG will increase when there are
fast changes. Limit the DG to obtain a pure differentiator gain at slow changes and a constant
differentiator gain where fast changes occur.
Function:
Enter the PID feed forward (FF) factor. The FF factor sends a constant fraction of the reference
signal to bypass the PID control, so the PID control only affects the remaining fraction of the control
signal. Any change to this parameter will thus affect the motor speed. When the FF factor is activated
it provides less overshoot, and high dynamics when changing the set point. par. 7-38
Feed Forward Factor
is active when par. 1-00
Function:
Enter the On Reference bandwidth. When the PID Control Error (the difference between the refer-
ence and the feedback) is less than the set value of this parameter the On Reference status bit is
high, i.e. =1.
®
MG.33.M8.02 - VLT is a registered Danfoss trademark
FC 300 Programming Guide
Configuration Mode
is set to [3] Process.
Process PID