YASKAWA SGD7S series Product Manual page 418

 Torque Reference Filter
As shown in the following diagram, the torque reference filter contains a first order lag filter and
notch filters arranged in series, and each filter operates independently.
The notch filters can be enabled and disabled with Pn408 = n.XX and Pn416 = n.XXX.
*
Torque
Fir t econd tage
reference tage fir t econd torque
torque reference
before filter
reference filter:
filter: Pn40F
Pn401 Pn410
Fir t order econd order
lag filter lag filter
*
The second stage second torque reference filter is disabled when Pn40F is set to 5,000 (default setting) and it is
enabled when Pn40F is set to a value lower than 5,000.
 Torque Reference Filter
If you suspect that machine vibration is being caused by the Servo Drive, try adjusting the
torque reference filter time constant. This may stop the vibration. The lower the value, the bet-
ter the control response characteristic will be, but there may be a limit depending on the
machine conditions.
First Stage First Torque Reference Filter Time Constant
Pn401 Setting Range
0 to 65,535
Second Stage Second Torque Reference Filter Frequency
Pn40F Setting Range
100 to 5,000
Second Stage Second Torque Reference Filter Q Value
Pn410 Setting Range
50 to 100
*
The filter is disabled if you set the parameter to 5,000.
 Notch Filters
The notch filter can eliminate specific frequency elements generated by the vibration of sources
such as resonance of the shaft of a ball screw.
The notch filter puts a notch in the gain curve at the specific vibration frequency (called the
notch frequency). The frequency components near the notch frequency can be reduced or
removed with a notch filter.
Notch filters are set with three parameters for the notch filter frequency, notch filter Q value,
and notch filter depth. This section describes the notch filter Q value and notch filter depth.
Torque-Related
Function
election 1
Pn408
Fir t econd
tage tage
notch filter: notch filter:
Pn409 Pn40C
Pn40A Pn40D
Pn40B Pn40E
Notch filter Notch filter
Setting Unit Default Setting
0.01 ms 100
Setting Unit Default Setting
1 Hz 5000*
Setting Unit Default Setting
0.01 50
8.13 Manual Tuning
8.13.1 Tuning the Servo Gains
Torque-Related
Function
election 2
Pn416
Fourth
Third
tage tage
notch filter:
notch filter: notch filter:
Pn417 Pn41A
Pn41B
Pn418
Pn419 Pn41C
Notch filter Notch filter Notch filter
Speed Position
When Enabled
Immediately
Speed Position
When Enabled
Immediately
Speed Position
When Enabled
Immediately
Torque
Fifth
tage
reference
after filter
Pn41D
Pn41E
Pn41F
Torque
Classification
Tuning
Torque
Classification
Tuning
Torque
Classification
Tuning
8
8-79