KMB NOVAR 2600, Руководство по эксплуатации

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NOVAR 2600 Operating Manual
4.2.1.4 Control Deviation Flags
Just below the power factor gauges there are control deviation flags – three particular ones for
each phase L1, L2, L3 a one total three-phase ( ΣL ) flag.
These flags show the magnitude of deviation of the instantaneous reactive power in the power system
from tolerable reactive power range defined by the specified value of required power factor and control
bandwidth. Numeric value of this quantity,
the ΔQfh , can be viewed at appropriate folder of the actual
data&status panel ( described further below).
If the deviation is smaller than a half of the reactive power value of the smallest output, the flag is
suppressed (balanced state). If the deviation is greater than a half of, but smaller than the reactive
power value of the smallest output, the corresponding flag flashes — if lagging (undercompensation,
positive ΔQfh value ), the
(choke) flag flashes; if leading (overcompensation, negative ΔQfh
value ), the (capacitor) flag flashes. If the deviation exceeds the value of the smallest output, the
corresponding flag is shown permanently.
The flags are evaluated both individually for each phase by corresponding phase deviation
( considering the smallest corresponding phase reactive power component ) and for total three-phase
outlet.
Exceptions to these flags’ meanings occur at the following situations when
the ΔQfh deviation cannot
be evaluated :
• if corresponding measurement phase voltage is below instrument sensitivity, the U=0
message is displayed instead
• if corresponding measurement phase voltage is correct, but corresponding measurement
current is below instrument sensitivity, the
I=0 message is displayed instead
• if both corresponding measurement phase voltage and current are correct, but no control
output with non-zero reactive power value is preset, the
C=0
message is displayed instead
During all of the situations above, the power factor control cannot be executed and the controller gets
into
the Standby mode.
4.2.1.5 Control Time Bargraph
At the control deviation flags' background, actual state of control time in form of horizontal
bargraph is displayed.
Power factor control passes discontinuously as a sequence of control interventions . The period
between two consecutive control interventions is called control time .
Depending on preset control strategy (see further below), one control time only or more times are
counted down. If the 3p strategy is set, one common (“three-phase”) control time is evaluated and its
bargraph shown in the ΣL control deviation flag field. For the
3p+1p
or
3x1p
strategies, three
individual control times for each independently controlled phase are evaluated and their bargraphs
shown in corresponding L1, L2, L3 control deviation flag fields.
As soon as the control deviation exceeds one half of appropriate smallest output power, the control
time counter is filled with appropriate preset control time value (depending on the deviation polarity)
and starts to count down. At the same time, appropriate control time bargraph starts to grow to the
right. Over time, the control deviation flag field background is fully filled, that means that the control
time counter has expired. Just after that new control intervention occurs and the control process
continues again from the beginning.
If the control deviation drops down below one half of the smallest output power, the control time
counter is refilled with the preset control time, the countdown stops and the appropriate bargraph is
cleared. But there are two exceptions to this – if :
•
either at least one control choke (or, generally, inductive character section) is switched on,
•
or there is very low load in the network
the control time counts down at minimum rate even during balanced state.
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