Panasonic A4P Series User Manual

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[Adjustment]
Adjustment
Damping Control
Outline
This function reduces the vibration by removing
the vibration frequency component from the com-
mand when the load end of the machine vibrates.
Applicable Range
This function can only be applicable when the following conditions are satisfied.
Caution
    When you change the parameter setup or switch with VS-SEL, stop the action first then execute.
This function does not work properly or no effect is obtained under the following conditions.
How to Use
(1) Setup of damping frequency (1st : SV.Pr2B, 2nd : SV.Pr2D)
Measure the vibration frequency of the front edge of the machine.
When you use such instrument as laser displacement meter, and can
directly measure the load end vibration, read out the vibration fre-
quency from the measured waveform and enter it to SV.Pr2B or
SV.Pr2D (2nd vibration suppression frequency).
(2) Setup of damping filter (1st : SV.Pr2C, 2nd : SV.Pr2E)
First, set up 0.
You can reduce the settling time by setting up larger
value, however, the torque ripple increases at the
command changing point as the right fig. shows.
Setup within the range where no torque saturation
occurs under the actual condition. If torque satura-
tion occurs, damping control effect will be lost.
<Remark>
Limit the damping filter setup with the following formula.
10.0 [Hz] – Damping frequency 
<
=
 Damping filter setup
<
=
 Damping frequency
(3) Setup of damping filter switching selection
(SV.Pr24)
You can switch the 1st or the 2nd damping filter depending on the vibration condition of the machine.
Control mode
Conditions under which the damping control is activated
• Control mode to be either or both position control or/and full-closed control.
    SV.Pr02 = 0 : Position control
    SV.Pr02 = 6 : Full-closed control
Command 
speed
Position deviation
Calculation of 
vibration frequency
Torque 
command
Torque saturation
Damping filter setup is 
too large.
Damping filter setup is 
appropriate.
Switching mode
No switching ( Both of 2 are valid.)
Switch with command direction.
CCW : 1st damping filter
CW   : 2nd damping filter
SV.Pr24
0, 1
2
Servo driver
Motor position
Motor
Coupling
Ball
screw
Work
travel
Driver
PLC
Setup of front edge vibration 
frequency
Motor
Encoder
Load
Position 
command
Damping 
filter
Position/Velocity
control
Torque 
command 
Current
control
Machine 
base
Front edge vibrates.
Vibration 
measurement
with 
displacement
sensor
Motor 
current
Load
Conditions which obstruct the damping control effect
• Vibration is triggered by other factors than command (such as disturbance).
• Ratio of resonance frequency and anti-resonance frequency is large.
• Vibration frequency is out of the range of 10.0 to 200.0 [Hz].