Lenze DDS Global Drive PLC Developer Studio - Manual (Page 21)

Function block library LenzeElectricalShaft.lib
Special functions
2.1.2 Digital frequency processing (L_DFSET)
2−11
L
LenzeElectricalShaft.lib EN 1.2
2.1.2.2 Processing of correction values
Speed trimming
Speed trimming is used to add correction values, e.g. from a superimposed closed−loop control. This
allows acceleration or deceleration of the drive.
Speed trimming is implemented through addition
·
of an analog value at nSpeedTrim_a to the speed setpoint (16384
º n
max
(C0011))
or
·
a speed value at nSpeedTrim_v to the speed setpoint (16384
º 15000 rpm)
– The speed trimming via this input is more precise.
Phase trimming
With phase−angle trimming, a set value at nPositionTrimming is added to the speed setpoint. This
changes the rotor position forwards or backwards relative to the setpoint (drive leading or lagging)
depending on the number of increments applied.
The phase trimming can be performed within a range of ±32767 increments (corresponds to ±1/2
revolution).
·
The input is made in increments (one revolution corresponds to 65536 increments).
·
When analog values are entered, 100% correspond to 1/4 revolution = 16384 increments.
·
You can expand the range of adjustment by using the multiplier nAngleOffsetMult .
Phase offset
With the phase−angle offset dnPosOffset a fixed phase−angle shift is applied to the setpoint for the
drive.
Speed−proportional phase setting
The phase−angle shift enables a leading or lagging of the phase with rising speed.
·
In nSpeedDependPosOffset a corresponding adjustment can be entered in increments.
·
The set phase offset is reached at 15000 rpm of the drive (linear relationship).