sh030051g.pdf - 第168页
7 - 11 7. SPECIAL ADJUSTMENT FUNCTIONS 7.6.2 Function block diagram The valid loop gains PG2, VG2, VIC and GD2 of the actual loop are c hanged according to the conditions selected by gain changing selection CD P (paramet…
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7. SPECIAL ADJUSTMENT FUNCTIONS
7.5 Low-pass filter
(1) Function
When a ball screw or the like is used, resonance of high frequency may occur as the response level of the
servo system is increased. To prevent this, the low-pass filter is factory-set to be valid for a torque
command. The filter frequency of this low-pass filter is automatically adjusted to the value in the following
expression.
Filter frequency(rad/s)
1 + GD2
VG2
10
When parameter No.PB23 is set to "
1 ", manual setting can be made with parameter No.PB18.
(2) Parameter
Set the operation of the low-pass filter selection (parameter No.PB23.)
Parameter No.PB23
Low-pass filter selection
0: Automatic setting (initial value)
1: Manual setting (parameter No.PB18 setting)
7.6 Gain changing function
This function can change the gains. You can change between gains during rotation and gains during stop or
can use an input device to change gains during operation.
7.6.1 Applications
This function is used when.
(1) You want to increase the gains during servo lock but decrease the gains to reduce noise during rotation.
(2) You want to increase the gains during settling to shorten the stop settling time.
(3) You want to change the gains using an input device to ensure stability of the servo system since the load
inertia moment ratio varies greatly during a stop (e.g. a large load is mounted on a carrier).
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7. SPECIAL ADJUSTMENT FUNCTIONS
7.6.2 Function block diagram
The valid loop gains PG2, VG2, VIC and GD2 of the actual loop are changed according to the conditions
selected by gain changing selection CDP (parameter No.PB26) and gain changing condition CDS (parameter
No.PB27).
GD2
Parameter No.PB06
GD2B
Parameter No.PB29
PG2
Parameter No.PB08
PG2B
Parameter No.PB30
VG2
Parameter No.PB09
VG2B
Parameter No.PB31
VIC
Parameter No.PB10
VICB
Parameter No.PB32
CDS
Parameter No.PB27
VRF1
Parameter No.PB19
VRF1B
Parameter No.PB33
VRF2
Parameter No.PB20
VRF2B
Parameter No.PB34
Command pulse
frequency
Droop pulses
Model speed
Control
command of
controller
Comparator
Changing
Valid
GD2 value
Valid
PG2 value
Valid
VG2 value
Valid
VIC value
Valid
VRF1 value
Valid
VRF2 value
CDP
Parameter No.PB26
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7. SPECIAL ADJUSTMENT FUNCTIONS
7.6.3 Parameters
When using the gain changing function, always set "
3" in parameter No.PA08 (auto tuning) to choose the
manual mode of the gain adjustment modes. The gain changing function cannot be used in the auto tuning
mode.
Parameter No. Abbreviation Name Unit Description
PB06 GD2
Ratio of load inertia moment to
servo motor inertia moment
Multi-
plier
(
1)
Control parameters before changing
PB07 PG1 Model loop gain rad/s
Position and speed gains of a model used to set the
response level to a command. Always valid.
PB08 PG2 Position loop gain rad/s
PB09 VG2 Speed loop gain rad/s
PB10 VIC Speed integral compensation ms
PB29 GD2B
Gain changing ratio of load inertia
moment to servo motor inertia
moment
Multi-
plier
(
1)
Used to set the ratio of load inertia moment to servo motor
inertia moment after changing.
PB30 PG2B Gain changing position loop gain 2 rad/s
Used to set the value of the after-changing position loop
gain 2.
PB31 VG2B Gain changing speed loop gain 2 rad/s
Used to set the value of the after-changing speed loop
gain.
PB32 VICB
Gain changing speed integral
compensation
ms
Used to set the value of the after-changing speed integral
compensation.
PB26 CDP Gain changing selection Used to select the changing condition.
PB27 CDS Gain changing condition
kpps
pulse
r/min
Used to set the changing condition values.
PB28 CDT Gain changing time constant ms
You can set the filter time constant for a gain change at
changing.
PB33 VRF1B
Gain changing vibration suppression
control vibration frequency setting
Hz
Used to set the value of the after-changing vibration
suppression control vibration frequency setting.
PB34 VRF2B
Gain changing vibration suppression
control resonance frequency setting
Hz
Used to set the value of the after-changing vibration
suppression control resonance frequency setting.