MITSUBISHI ELECTRIC MELSERVO MR-J2S- A - Manual (Page 184)

8 - 3
8. SPECIAL ADJUSTMENT FUNCTIONS
POINT
If the frequency of machine resonance is unknown, decrease the notch
frequency from higher to lower ones in order. The optimum notch
frequency is set at the point where vibration is minimal.
A deeper notch has a higher effect on machine resonance suppression but
increases a phase delay and may increase vibration.
The machine characteristic can be grasped beforehand by the machine
analyzer on the MR Configurator (servo configuration software). This
allows the required notch frequency and depth to be determined.
Resonance may occur if parameter No. 58 59 is used to select a close
notch frequency and set a deep notch.
(b) Machine resonance suppression filter 2 (parameter No. 59)
The setting method of machine resonance suppression filter 2 (parameter No. 59) is the same as
that of machine resonance suppression filter 1 (parameter No. 58). However, the machine
resonance suppression filter 2 can be set independently of whether adaptive vibration suppression
control is valid or invalid.
8.3 Adaptive vibration suppression control
(1) Function
Adaptive vibration suppression control is a function in which the servo amplifier detects machine
resonance and sets the filter characteristics automatically to suppress mechanical system vibration.
Since the filter characteristics (frequency, depth) are set automatically, you need not be conscious of
the resonance frequency of a mechanical system. Also, while adaptive vibration suppression control is
valid, the servo amplifier always detects machine resonance, and if the resonance frequency changes,
it changes the filter characteristics in response to that frequency.
Mechanical
system
response
level Mechanical
system
response
level
Machine resonance point Machine resonance point
Frequency Frequency
Notch
depth Notch
depth
Notch frequency Notch frequency
Frequency Frequency
When machine resonance is large and frequency is low When machine resonance is small and frequency is high
POINT
The machine resonance frequency which adaptive vibration suppression
control can respond to is about 150 to 500Hz. Adaptive vibration
suppression control has no effect on the resonance frequency outside this
range. Use the machine resonance suppression filter for the machine
resonance of such frequency.
Adaptive vibration suppression control may provide no effect on a
mechanical system which has complex resonance characteristics or which
has too large resonance.
Under operating conditions in which sudden disturbance torque is imposed
during operation, the detection of the resonance frequency may malfunction
temporarily, causing machine vibration. In such a case, set adaptive
vibration suppression control to be "held" (parameter No. 60: 2 ) to fix
the characteristics of the adaptive vibration suppression control filter.