BONFIGLIOLI active cube 201, Руководство по эксплуатации

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232 Operating Instructions ACU 12/16
18.5.6.1 Limitation of field controller
The output signal of the field controller, the integrating and proportional component are limited via
parameters
Ref. Isd Upper Limit
743 and
Ref. Isd Lower Limit
744 . During guided commissioning,
parameter
Ref. Isd Upper Limit
743 is set according to parameter
Rated Current
371 .
Parameter Setting
No. Description Min. Max. Factory setting
743 Ref. Isd upper limit 0 o  I
FIN
I
FIN
744 Ref. Isd lower limit - I
FIN
I
FIN
0.0
The limits of the field controller define not only the maximum current occurring, but also the
dynamic properties of the controller. The upper and lower limits restrict the modification speed of
the machine flux and the torque resulting from it. In particular the speed area above the nominal
frequency should be observed for the modification of the flux-forming component. The upper limit is
to be estimated from the product of the set magnetizing current and the correction factor
Reference
Flux
717 , although the limit must not exceed the overload current of the drive.
18.5.7 Modulation controller
The modulation controller, which is designed as an I regulator, automatically adapts the output value
of the frequency inverter to the machine behavior in the basic speed area and in the field weakening
area. If the modulation exceeds the figure set with parameter
Reference Modulation
750 , the field-
forming current component and thus the flux in the machine are reduced.
In order to make the best possible use of the voltage available, the figure selected via parameter
Operation Mode
753 is put into proportion to the DC link voltage. That means that with a high mains
voltage there is also a high output voltage available, the drive only reaches the field weakening area
later and produces a higher torque.
Operation Mode 753 Function
0 - Usq-Control
The modulation is calculated from the ratio of torque-forming voltage
component U
sq
to the DC link voltage.
1 - U abs. value control
The modulation is calculated from the abs. voltage value / DC link
voltage ratio.
The integrating part of the modulation controller is to be set via parameter
Integral Time
752 .
Parameter Setting
No. Description Min. Max. Factory setting
750 Reference modulator 3.00 % 105.00 % 102.00 %
752 Integral Time 0.0 ms 1000.0 ms 10.0 ms
The percentage setting of the
Reference Modulation
750 is basically a function of the leakage
inductance of the machine. The default value was selected such that in most cases the remaining
deviation of 5% is sufficient as a reserve range for the current controller. For the optimization of the
controller parameters, the drive is accelerated with a flat ramp into the area of field weakening, so
that the modulation controller intervenes. The limit is set via
parameter Reference Modulation
750 .
Then, the control loop can be excited with a jump function by modifying the reference modulation
(change-over between 95% and 50%). By means of an oscillographed measurement of the flux-
forming current component on the analog output of the frequency inverter, the controlling process
of the modulation controller can be assessed. The course of the signal of the flux-forming current I
sd
should reach the stationary value after overshooting without oscillation. An oscillating of the course
of the current can be damped by increasing the integral time. Parameter
Integral Time
752 should
roughly correspond to the actual value
Act. Rotor Time Constant
227 .