BONFIGLIOLI active cube 201, Руководство по эксплуатации

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202 Operating Instructions ACU 12/16
17 V/f characteristic
The sensorless control in configurations 110 and 111 is based on the proportional change of output
voltage compared to the output frequency according to the configured characteristic.
By setting the V/f-characteristic, the voltage of the connected 3-phase motor is controlled according
to the frequency. The torque to be applied by the motor at the corresponding operating point
demands the control of the output voltage proportional to the frequency. At a constant output
voltage / output frequency ratio of the frequency inverter, the magnetization is constant in the
nominal operating range of the 3-phase motor. The rating point of the motor or end point of the V/f-
characteristic is set via the guided commissioning with parameter
Cut-Off Voltage
603 and
parameter
Cut-Off Frequency
604 .
The lower frequency range, where an increased voltage is necessary for the start of the drive, is
critical. The voltage at output frequency = zero is set with the parameter
Starting Voltage
600 . A
voltage increase deviating from the linear course of the V/f characteristic can be defined by
parameters
Voltage Rise
601 and
Rise Frequency
602 . The parameter value percentage is
calculated from the linear V/f characteristic. Via parameters
Minimum Frequency
418 and
Maximum
Frequency
419 , the working range and/or V/f characteristic are defined.
603 (UC)
601 (UK)
600 (US)
U
418 (FMIN)
419 (FMAX)
602 (FK)
604 (FC) f
Working range
(FMIN):
Minimum Frequency
418
, (FMAX):
Maximum Frequency
419
,
(US):
Starting Voltage
600
,
(UK):
Voltage Rise
601
, (FK):
Rise Frequency
602
(UC):
Cut-Off Voltage
603
, (FC):
Cut-Off Frequency
604
Parameter Setting
No. Description Min. Max. Factory setting
600 Starting voltage 0.0 V 100.0 V 5.0 V
601 Voltage rise -100 % 200 % 10 %
602 Rise frequency 0 % 100 % 20 %
603 Cut-off voltage 60.0 V 560.0 V 400.0 V
604 Cut-off frequency 0.00 Hz 599.00 Hz 50.00 Hz
The guided commissioning takes the parameterized rated motor values and reference
data of the frequency inverter into account when it comes to pre-setting the V/f-
characteristic. In the case of asynchronous machines, the speed can be increased at a
constant torque if the motor winding can be switched over from star to delta
connection. If the data for delta connection indicated on the rating plate of the three-
phase motor were entered, the cut-off frequency is increased automatically by the
square root of three.