Vibration Suppression Command Filter; Vibration Suppression Command Filter Operation - Mitsubishi Electric MELSEC iQ-R16MTCPU Programming Manual

7.9

Vibration Suppression Command Filter

The vibration suppression command filter function is used to suppress vibrations in position control on the load-side such as
vibrations of the work platform and shaking of the machine frame. The function is used to suppress vibrations of low
frequencies that cannot be set in a filter such as the servo amplifier command notch filter, and applications where frequency is
changed during operation. By setting the vibration frequency, a command that suppresses that frequency is generated, thus
controlling vibration. Up to two vibration suppression command filters can be set simultaneously to one servo amplifier axis.
When activating the vibration suppression command filter, the vibration suppression command filter data for each axis must
be set. Refer to vibration suppression command filter data for details of vibration suppression command filter data. ( Page
211 Vibration Suppression Command Filter Data)
The control modes that support vibration suppression command filter are shown in the chart below.
The vibration suppression command filter is only valid in positioning control mode, however if the filter is set during home
position return, it stays invalid.
: Valid : Invalid
Control mode
Positioning control mode
Speed control mode
Torque control mode
Continuous operation to torque control mode
Pressure control mode

Vibration suppression command filter operation

There are two types of filter that are set in vibration suppression command filter data: "Vibration suppression command filter
1", and "Vibration suppression command filter 2".
Before starting positioning control, set the "frequency" of "vibration suppression command filter 1" and "vibration suppression
command filter 2", and change "mode selection device" in "vibration suppression command filter 1" and "Vibration
suppression command filter 2" from "0: Invalid" to the filter method to be set (1: Smoothing filter, 2: FIR filter, 3: IIR filter).
Smoothing filter and FIR filter can be set to vibration suppression command filter 1. When changing settings such as the filter
frequency, change with the status of the device set in command output complete signal after filter turned ON. If the value is
changed while the filter is operating, the filter becomes invalid.
IIR filter can be set to vibration suppression command filter 2. When IIR filter is set, the filter frequency setting can be changed
immediately during positioning operation.
Parameters written from MT Developer2 are fetched by turning the power supply of the Multiple CPU system OFF and ON
again. When parameter settings are changed, turn the Multiple CPU system back ON again, or reset the system.
Filter method selection
The operation examples and application examples for filter method selection are shown below.
■Application examples
Application example
Minimizing torque change of the motor
Suppressing a frequency below 1Hz
Minimizing the command delay caused by the filter
Changing frequency during positioning operation
Suppressing more than one frequency
Vibration suppression command filter valid/invalid
 (Invalid during speed control() and during home position return)

Filter method
Smoothing filter
Smoothing filter
FIR filter
FIR filter
IIR filter
Use filter methods together
• Low frequency: Smoothing filter or FIR filter
• High frequency: IIR filter
7 AUXILIARY AND APPLIED FUNCTIONS
7.9 Vibration Suppression Command Filter
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