7-03 Speed PID Integral Time
Range:
Function:
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 1-00 Configuration Mode
.
7-04 Speed PID Differentiation Time
Range:
Function:
Size
related
*
[0 -
200 ms]
Enter the speed controller differentiation
time. 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 differen-
tiator. The gain is proportional with the
speed at which errors change. Setting this
parameter to 0 disables the differentiator.
This parameter is used with
parameter 1-00 Configuration Mode
[1] Speed
closed loop
control.
7-05 Speed PID Diff. Gain Limit
Range:
Function:
5
*
[1 -
20 ]
Set a limit for the gain provided by the differen-
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 1-00 Configuration Mode
[1] Speed closed
loop
control.
7-06 Speed PID Lowpass Filter Time
Range:
Function:
Size
related
*
[0.1
- 100
ms]
NOTICE
Severe filtering can be detrimental to
dynamic performance.
This parameter is used with
parameter 1-00 Configuration Mode
[1]
Speed closed loop
and
[2] Torque
control.
Adjust the filter time in flux sensorless to
3–5 ms.
Set a time constant for the speed control low-
pass filter. The low-pass filter improves steady-
state performance and dampens oscillations on
the feedback signal. This is an advantage if
there is a great amount of noise in the system,
see
. For example, if a time
constant (τ) of 100 ms is programmed, the cut-
off frequency for the low-pass filter is 1/0.1 =
10 RAD/s, corresponding to (10/2 x π) = 1.6 Hz.
The PID regulator only regulates a feedback
7-06 Speed PID Lowpass Filter Time
Range:
Function:
signal that varies by a frequency of less than 1.6
Hz. If the feedback signal varies by a higher
frequency than 1.6 Hz, the PID regulator does
not react.
Practical settings of
taken from the number of
pulses per revolutions from encoder:
Encoder PPR
Parameter 7-06 Speed PID
Lowpass Filter Time
512
10 ms
1024
5 ms
2048
2 ms
4096
1 ms
Table 3.25 Speed PID Lowpass Filter Time
Parameter Descriptions
Programming Guide
MG33MP02
Danfoss A/S © 10/2018 All rights reserved.
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Summary of Contents for VLT AutomationDrive FC 302
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