Power /Frequency Reference - Danfoss Vacon NXP Applications Manual

62 · vacon
2.2.3.4 DC Reference Offset
Offset for DC Reference, used to balance parallel unit active current while using same
DC Reference P2.2.1. in all units.
5.2.2

Power /frequency reference

2.2.4.1 Frequency Drooping Offset
This parameter is used to adjust the base frequency for drooping purposes. For example,
if drooping is set to 2 Hz this parameters can be set to 1 Hz so that when the load is 50%,
the frequency will be at the nominal point. The offset can also be set by the supply
frequency parameters. However, in that case the grid frequency protection function will
also use this increased value as a reference point and makes the protection function
activate at the wrong frequency.
When you use this parameter for drooping purposes, the supply frequency can be left to
the nominal value.
Final frequency reference is also limited by G2.9.7 frequency warning limits.
2.2.4.2 Frequency Down (DigIn)
Select a digital input to decrease the base frequency with a set ramp rate.
See also ID1700 FB Micro Grid CW1 Bit 4 Power Down
2.2.4.3 Frequency Up (DigIn)
Select a digital input to increase the base frequency with a set ramp rate. Frequency
change is also limited by G2.3 Ramp Time and Ramp Range.
See also ID1700 FB Micro Grid CW1 Bit 5 Power Up
2.2.4.6 Base Current Reference
The Base Current Reference determines offset for frequency reference within Frequency
Drooping. For example, if frequency drooping is set to 2.000 Hz and grid frequency is
constant 50 Hz with very small or nonexistent changes (isochronous or strong grid), and
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Description of parameters
Figure 14.
ID417
ID418
ID1533
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Unfiltered
1 s filter time
63 %
FreqRef 2nd
order