Low-Frequency Vibration Suppression In Position Mode - Delta ASDA-B3 Series User Manual

Control Mode
When you set the value of KPP (P2.000) too high, the bandwidth for the position loop is
increased and the phase margin is reduced. Meanwhile, the rotor rotates and vibrates in the
forward and reverse directions. Then, you have to decrease the KPP value until the rotor stops
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vibrating. When the external torque is too high, the low value for KPP cannot meet the demand
of reducing the position following error. In this case, increasing the position feed forward gain,
PFG (P2.002), can effectively reduce the position following error.
The actual position profile changes from (1) to (3) with the increase in the KPP value.
(4) stands for the Position command.

6.2.9 Low-frequency vibration suppression in Position mode

If the machine is too flexible, vibration persists even when the motor stops after the positioning
command is complete. The low-frequency vibration suppression function can reduce the
machine vibration. The suppression range is between 1.0 Hz and 100.0 Hz. You can use this
function with either auto or manual setting.
Auto setting
If you have difficulty finding the frequency, enable the auto low-frequency vibration suppression
function, which automatically searches for the vibration frequency.
When you set P1.029 to 1, the system automatically disables the auto low-frequency vibration
suppression function (by setting P1.026 and P1.028 to 0) and starts to search for the vibration
frequency. When the detected frequency remains at the same level, the system automatically
changes the settings in the following order.
1. Sets P1.029 to 0.
2. Sets P1.025 to the first frequency and sets P1.026 to 1.
3. Sets P1.027 to the second frequency and sets P1.028 to 1.
When P1.029 is automatically reset to 0, but the low-frequency vibration persists, check if
P1.026 or P1.028 is set to 1. If either P1.026 or P1.028 is 1, increase the setting of P1.030
(low-frequency vibration detection). If the values of P1.026 and P1.028 are both 0, it means no
vibration frequency is detected. In this case, lower the value of P1.030 and set P1.029 to 1 to
search for the vibration frequency again. Note that when you set the detection level too low, it
might detect noise as the low-frequency vibration.
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ASDA-B3