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

Parameter Descriptions

3.22 PI-## PID Controls

Parameter group related to PID Controls
3.22.1 PI-0# Speed PID Control
Parameters to configure the Speed PID Control.
PI-00 Speed PID Feedback Source
Option: Function:
NOTICE
This parameter cannot be
adjusted while the motor is
running.
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 parameter H-42 Flux Motor
Feedback Source.
[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-01 Speed PID Droop
The droop function allows the frequency converter to decrease
the motor speed proportional to the load. The droop value is
directly proportional to the load value. Use the droop function
when several motors are mechanically connected and the load
on motors can differ.
Ensure that parameter P-09 Slip Compensation has a default
setting.
Range:
0 RPM [0 - 200 RPM]
*
PI-02 Speed PID Proportional Gain
Range: Function:
0.015 [0 - 1] Enter the speed controller proportional gain.
*
Quick control is obtained at high amplification.
However, if amplification is too great, the
process may become unstable.
DET-618D
AF-650 GP™ Programming Guide
8
ms
30.0
ms
5
Function:
Enter the droop value at
100% load.
02/2016 All rights reserved.
PI-03 Speed PID Integral Time
Range: Function:
[1.0 - Enter the speed controller integral time, which
20000 determines the time the internal PID control
*
ms] 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 [0] Speed open loop and [1] Speed closed
loop control, set in parameter H-40 Configuration
Mode.
PI-04 Speed PID Differentiation Time
Range: Function:
[0 - Enter the speed controller differentiation time.
200 ms] The differentiator does not react to constant
*
error. It provides 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
parameter H-40 Configuration Mode [1] Speed
closed loop control.
PI-05 Speed PID Diff. Gain Limit
Range: Function:
[1 - Set a limit for the gain provided by the differen-
*
20] tiator. Consider limiting the gain at higher
frequencies. For example, set up a pure D-link at
low frequencies and a constant D-link at higher
frequencies. This parameter is used with
parameter H-40 Configuration Mode [1] Speed closed
loop control.
3 3
151