Speed Synchronization; Figure 8: Control Behaviour With Speed Synchronization; Figure 9: Mixing. Speed Synchronizing Control - Danfoss VLT 5000 Operating Instructions Manual

Speed synchronization

The speed synchronization controller raise or lower the speed of the slave drive matching it to the
calculated master speed taking the gear ratio into account. – There is no position control.
In the above diagram, it can be seen that the slave drive is following the speed of the master drive.
Note: Position deviations arising in connection with speed changes are not adjusted. This type of
control could for example be used for dosing pumps mixing two liquids. See example.
The example shows a batching unit where an admixture to a basic substance is carried out. The
mixing proportion is freely selectable by means of the gear ratio. The advantage of pure speed
synchronizing control can also be seen, as it makes little sense to compensate for position deviations
that arise (i.e. too large an amount of Product B being added, for example) by means of reducing the
speed of the slave drive, as that would only lead to an insufficient amount of Product B being added
subsequently.
MG.10.N4.02 - VLT is a registered Danfoss trademark
Synchronizing controller

Figure 8: Control behaviour with speed synchronization

Figure 9: Mixing. Speed synchronizing control

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