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5 Servo Adjustment
MITSUBISHI CNC
< Notch filter frequency adaptive tracking function >
Machine system resonance can vary depending on secular changes or installation conditions of machine,
resonance frequency may deviate from the notch filter frequency set at the initial adjustment. The adaptive tracking
function estimates minor changes in resonance frequency from current command oscillating component,
automatically adjusting notch filter effective frequency. The resonance frequency is estimated while G0 is moving
and effective frequency is modified while the axis is stopped.
The adaptive tracking function can be applied to notch filter 1, 2, 4, 5 (SV038, SV046, SV087, SV088). When
resonance frequency is detected within the adaptive ranges which centers in the frequency set by parameter,
resonance frequency from which notch filter effective frequency with the closest setting value is detected,
suppressing machine resonance.
<Other specifications>
(a) Machine resonance is detected at frequency ranges of 150Hz to 90Hz.
(b) The depth of notch filter is not automatically adjusted. Only the effective frequency will change while the filter
depth remains fixed.
(c) When the notch filter 5 is adaptive to all frequency and also, others are not available, the effective frequency of
notch filter 5 is changed.
(d) When parameter setting value is changed; if the effective frequency remains within the adaptive ranges, it will
keep operating with the original frequency; if it doesn't, changed parameter value will be applied.
Notch filter application ranges when the adaptive tracking function is available
Notch filter
Estimated adaptive
frequency range
Avail. Adaptive
operation
Adaptive range
Notch filter 1 150 to 900 [Hz] SV115/bit8 Setting value(SV038)±Adaptive range (SV115/bit4,5) [Hz]
Notch filter 2 150 to 900 [Hz] SV115/bit9 Setting value (SV046)±Adaptive range (SV115/bit4,5) [Hz]
Notch filter 3 Not included Not included Not included
Notch filter 4 150 to 900 [Hz] SV115/bitA Setting value (SV087)±Adaptive range (SV115/bit4,5) [Hz]
Notch filter 5 150 to 900 [Hz] SV115/bitB
Setting value (SV088)±Adaptive range (SV115/bit4,5) [Hz]
(Note) When adaptive to all frequency (SV115/bitF) 150 to 900 [Hz]
CAUTION
If adaptive ranges are set too wide, frequency may fluctuate so greatly that the control can become unstable.
When the notch filter 5 is set adaptive to all frequency, the depth of the filter shall be set shallowly to enable stable
operation with low frequency.
