Pi-## Pid Controls - GE AF-650 GP Programming Manual

3.21 PI-## PID Controls

Parameter group related to PID Controls
3.21.1 PI-0# Speed PID Control
Parameters to configure the Speed PID Control.
PI-00 Speed PID Feedback Source
Option:
[0] * Motor feedback par. H-42
[1] 24V encoder
[2] OPCENC
[3] OPCRES
[6] Analog Input 53
[7] Analog Input 54
[8] Frequency input 29
[9] Frequency input 33
PI-02 Speed PID Proportional Gain
Range:
0* [0.0000 - 1.0000]
PI-03 Speed PID Integral Time
Range:
8.0 ms* [2.0 - 20000.0 ms]
PI-04 Speed PID Differentiation Time
Range:
30.0 ms* [0.0 - 200.0 ms]
PI-05 Speed PID Diff. Gain Limit
Range:
5.0* [1.0 - 20.0]
Function:
Select the encoder for closed loop feedback.
The feedback may come from a different encoder (typically mounted on the application itself) than the
motor mounted encoder feedback selected in par. H-42 Flux Motor Feedback Source.
This parameter cannot be adjusted while the motor is running.
Function:
Enter the speed controller proportional gain. Quick control is obtained at high amplification. However if
amplification is too great, the process may become unstable.
Function:
Enter the speed controller integral time, which determines the time the internal PID control takes to correct
errors. The greater the error, the more quickly the gain increases. The integral time causes a delay of the
signal and therefore a dampening effect, and can be used to eliminate steady state speed error. Obtain
quick control through a short integral time, though if the integral time is too short, the process becomes
unstable. An excessively long integral time disables the integral action, leading to major deviations from
the required reference, since the process regulator takes too long to regulate errors. This parameter is
used with Speed open loop [0] and Speed closed loop [1] control, set in par. H-40 Configuration Mode.
Function:
Enter the speed controller differentiation time. The differentiator does not react to constant error. It pro-
vides gain proportional to the rate of change of the speed feedback. The quicker the error changes, the
stronger the gain from the differentiator. The gain is proportional with the speed at which errors change.
Setting this parameter to zero disables the differentiator. This parameter is used with par. H-40 Config-
uration Mode Speed closed loop [1] control.
Function:
Set a limit for the gain provided by the differentiator. Since the differential gain increases at higher fre-
quencies, limiting the gain may be useful. For example, set up a pure D-link at low frequencies and a
constant D-link at higher frequencies. This parameter is used with par. H-40 Configuration Mode Speed
closed loop [1] control.
AF-650 GP Programming Guide
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