4.4 Resonance suppressions
4.4 Resonance suppressions
When the mechanical system has the resonance effect, it is possibly created by higher rigidity of the servo
system and quicker response. It may improve if reduce the gain. The servo driver provides the low pass filter.
Under unchanging the gain by using filters can achieve the effect of resonance suppression.
The parameters related to Resonating suppression as follows:
Para
meter
P007
Name
Time constant of filter for torque
Range
0.10～50.00
Default
value
2.50
Unit Usage
ms ALL
The low pass filter is active by default. The parameter P007 is used to setting the time constant of torque filter.
The low pass filter has the very good weaken effect on high frequency and can suppress high frequency resonance
and noise. For example, the machinery with ball bearing screw sometimes can have high frequency resonance if
increasing the gain. Using low pass filter can get better effect, but the system response bandwidth and the phase
allowance also reduced, the system may become unstable.
When the high frequency vibration caused by the servo driver, adjust the filter time-constant Tf of torque,
possibly can eliminate the vibration. The smaller the value, the better control response achieves, but it is limited
by mechanical condition. ; The bigger the value, the better suppressing effect achieves on high frequency vibration,
but the phase allowance reduces and can cause the oscillation if the value is too big. If the load inertia ratio is set
correctly G (G=JL/JM), must satisfy the following condition:
Tf
(ms)
≤
2π
×
1000
2 × Kv (Hz)
49
