Parker Hannifin G2 manual Velocity Control Part, Related parameters #51 Velocity control bandwidth

5.4.1Velocity Control Part

For the velocity control bandwidth, either the value set with the #51 Velocity control bandwidth 1 parameter or the #49 Velocity control bandwidth 2 parameter is selected, according to the status of the controller interface input signal IN_GAIN. The selected value is displayed in the #376 Velocity control bandwidth monitor.

The velocity control part calculates the #361 Velocity proportional gain monitor value from the #155 Load inertia/load mass parameter value, which is either measured and set by an auto-tuning operation or entered directly as a numerical value, according to the velocity control bandwidth value. During this process, the frequency characteristics of neither the velocity feedback filter nor the notch filter are considered but only the frequency characteristic of the first order delay compensation device is considered to calculate the velocity proportional gain.

The first order compensation device can be set in four ways via the #152 First order delay compensation device setting parameter. The first order delay compensation device has the effect that it improves the gain characteristics of the velocity control part. The frequency characteristics for each setting of the first order compensation device is shown below. Note that there is no frequency dependency when the first order compensation is not set.

There are two channels available for the notch filter (optional). The central frequency value can be set independently for each channel via the #153 Notch filter: Frequency selection 1 and #154 Notch filter: Frequency selection 2 parameters. The notch filter has the effect that it improves the gain characteristics of mechanical systems that tend to resonate.

The velocity feedback filter can be enabled or disabled by setting the #219 Enable/Disable velocity feedback filter parameter. When enabled, the filter bandwidth can be set in the #220 Velocity feedback filter bandwidth parameter. The velocity feedback filter is effective in eliminating noise at motor operation, but with a small bandwidth the velocity control part tends to oscillate.

The filter bandwidth of the velocity command filter can be set in the #221 Velocity command filter bandwidth parameter. The velocity command filter helps achieving smoother acceleration/deceleration, but with a small bandwidth the position control part tends to oscillate.

[Related parameters]

#51 Velocity control bandwidth

#152 First order delay compensation device setting #153 Notch filter: Frequency selection 1

#154 Notch filter: Frequency selection 2 #155 Load inertia/load mass

#219 Enable/Disable velocity feedback filter #220 Velocity feedback filter bandwidth #221 Velocity command filter bandwidth

20Hz/80Hz

30Hz/120Hz

40Hz/160Hz

20Hz/80Hz

30Hz/120Hz

40Hz/160Hz

[Frequency characteristics of the first order

delay compensation device]

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