ABB ACS880 Series, Руководство по прошивке

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Note: In scalar motor control mode, the output voltage can alternatively be
increased by adjusting the
U/f curve: by setting parameter 97.7 . The value of 97.7 ,
can be calculated as the ratio of the desired voltage and the nominal voltage. In
this example, the ratio is 440 V / 400 V = 110%. Set the value of
97.7 to 110% and
leave motor nominal voltage as 400 V.
Limits
There are two types of limitations that you must take into account when you use
the DC voltage boost function: limitations to the DC voltage reference and the
limitation to the drive output voltage.
The drive calculates the minimum and maximum limits for the User DC voltage
reference (
94.22 ). The calculation is based on the actual supply voltage and the
upper limit of the largest supply voltage range selection available for the drive
(
95.1 ). Limits are:
1. Minimum limit: Internal DC voltage reference ( U
dc,int
).
2. Maximum limit: Maximum DC voltage reference (
U
dc,max
).
For more information, see the table below and sections Internal DC voltage
reference (
U
dc,int
) and Maximum DC voltage reference (
U
dc,max
) .
This table summarizes the limits to the user-defined DC voltage reference and to
the drive output voltage.
Maximum drive
output voltage
with parameter
97.4 default value
Maximum DC
voltage reference
(
Udc,max)
Internal DC voltage
reference (
Udc,int)
1)
95.1 selection Drive
type
479 V 663 V 553 V 380…415 V xxxA-3
576 V 799 V 553 V 380…415 V xxxA-5
641 V 440…480 V
728 V 500 V
795 V 1102 V 764 V 525…600 V xxxA-7
981 V 660…690 V
1) See section
Internal DC voltage reference ( U
dc,int
) .
Internal DC voltage reference ( U
dc,int
)
Udc,int = Uac,rms × √2 × 1.03
where
Internal DC voltage reference Udc,int
124 Program features