ESTAmat PFC-N
D.No.13157 - Rev. 02
Operating Instruction MV1181
Page 19 of 36
311
Control algorithm
1/2/3/4
1.
Automatic:
The controller operates on the "Best Fit"
principle. This means the controller compares before each
switching operation, all in the step database stored step sizes
with the identified need for reactive power and choose
always the step which is the closest to the control target. If
the controller has several equal steps available, the number
of switching cycles automatically distributed to these steps.
2.
LIFO:
„Last In, First Out“ Switch on the outputs is always
done in the switching sequence 1-2-3-4-max. The switch off
is in the switching sequence been turned upside max-4-3-2-1.
3.
Kombifilter:
Special algorithm for combined filter banks.
The controller operates on the "best fit" principle as in
automatic mode. Unlike to automatic mode the controller is
connecting always at least the same or more capacitance
which is connected to the odd numbered outputs with the
even numbered outputs. If the controller has several equal
steps available, the number of switching cycles automatically
distributed to these steps.
4.
Progressive:
The controller switches if required, several
steps in sequence with a shorter switching time. From
software 1.04, the controller uses independently of the set
switching time always 1 sec. as switching time. Furthermore,
the automatic step size detection is disabled and the step
sizes need to enter by hand. The input of the step sizes
should be as accurate as possible, because the regulator
would otherwise tend to oscillate. Leaving the "Progressive"
algorithm and use a different algorithm, the set switching
time is used the step size detection is re-enabled.
312
Offset reactive power
Ct*Pt*7000
The set here offset reactive power is always added to the measured
reactive power. This means that the system can be capacitive, but
measurement of the utility records the required Pf. The set offset
reactive power also goes into the calculation of ▲Q, Pf, apparent
power, current and active power. The max. offset reactive power
that can be entered is calculated from the set current and voltage
transformer ratios.
313
Switching time asymmetrical
-127...127
The set factor multiplies the selected switching time in the
capacitive direction (fast switch on of steps and slow switch off). If
this factor is set with – as sign the function works vice versa.
Factory setting "1" (means symmetrical switching times for both
directions)
