Nidec Control Techniques Digitax-SF DA21223, Instruction Manual

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48
5. Settings
Digitax SF I
nstruction Man
ual
５. Parameters
No. 80.0
Position command filter 1:
Smoothing 1 - Moving average counter
Range Default Characteristics
1 to 6,250
(See below)
No. 81.0
Position command filter 4:
Smoothing 2 - Moving average counter
1 to 1,250
Function
Use
These items are used to smooth the speed changes
during
high deceleration/
acceleration, and can be used to suppress vibrations at settling time as well.
Use Filter 4 (Smoothing 2) first.
To increase the smoothing effect further, use Filter 1 (Smoothing 1).
A larger value makes acceleration and deceleration smoother, but the response will become slower.
See the table below for the delay time calculation formula.
Filter 4 (Smoothing 2) suppress the vibrations caused by the Gain FF compensation 2.
Motor Capacity Delay time Calculation Formula
50 W to 750 W 0.16 ms
×(moving average count) = delay time
1 kW to 2 kW 0.2 ms
■ Setup of Vibration Suppression
Positioning will take longer as much as the delay time specified above. Set this item within the range acceptable to the equipment.
① Check the vibration interval in waveforms of position
error
and torque command at settling time.
② Calculate the moving average count as described below.
③ Using Filter 4 may reduce the resonant vibrations.
④ If suppression of the vibrations is not effective enough, recalculate the moving average count based on the vibration interval,
and set it to Filter 1.
Motor Capacity Moving average count and Vibration interval to compress
50 W to 750 W 6,250
×(vibration interval [s]) = Moving average count
1 kW to 2 kW 5,000
Default
Motor Capacity Filter 1 Filter 4
50 W to 750 W 25 10
1 kW to 2 kW 20 10
The default value of Position command filter 1: Type (66.0) is 0 (no filter).
Prerequisite
Position command filter 1: Selection (66.0) = 1 (Smoothing 1)
Position command filter 4: Selection (66.1) = 1 (Enable)
Remark
Before setting this parameter, wait at least 3 secs after the motor stops. In addition, configure it
whe
n
the command pulse is not
present
.
Setting this parameter during pulse input or presence of residual pulse could cause positioning
failure.
The larger the setting is, the longer the delay time from command input
will be
.
Related To No. 66.0, No. 66.1
7
Tuning