NOVAR 2100/2200 Operating Manual
On the contrary, negative reserve means that actual control deviation cannot be compensated; the
negative RC/RL value contains size of missing capacitive/inductive compensation power. That means
is such case the compensation system is undersized and other capacitors/chokes should be installed.
When checking a compensation system capacity usually at least one week long period is observed.
You can use registered maximum and minimum of the reserve average values for this :
1. Check all of the compensation outputs' values and target power factor to be set properly.
2. Check and, if necessary, set suitable average method and evaluation period of the
P/Q/S
-
group (to which the RC/RL reserves belong ; see average values setup).
3. In the actual values scroll to the ΣQ value (symbols Σ VAr, see the navigation map), then
navigate to the fundamental harmonic branch with the
key to the ΣQfh value (until the
H
symbol appears). Now , with the ▼key switch to the control deviation ΣΔQfh value (symbols
Δ Σ VAr) and in this row navigate further right with the
key to the compensation reserve
powers ΣRC (symbols
Σ VAr C H
) or ΣRL (symbols
Σ VAr H L
).
4. Now, with the
key switch to avgmax or avgmin value of any of these values and clear up
registered maximum&minimum power values : press the
key and keep pressed until the
value starts flashing, then change it with an arrow key to the
C
L
r
and confirm with the
key again. Because of just cleared, undefined value
-
-
-
appears.
5. Now let the controller running for reporting period (usually at least one week). After that,
check new registered maximum and minimum average values of reserve powers.
Compensation Reserves - Compensation Reserves -
Sufficient Insufficient Capacitive Reserve
For compensation reactive power capacity assessment,
registered minimum values
of both reserves
are decisive. On the left example above, registered minimum of three-phase capacitive reserve is 31.3
kvars, minimum of inductive reserve is 7.97 kvars. As both of them are positive the system
compensation power is sufficient.
If any of reserve minimum values is negative as example on the right example shows, reactive power
of magnitude that the controller could not compensate appeared sometimes in the network during the
testing period. As
the ΣRC
minimum average value is negative, the capacity of compensation
capacitors is not sufficient ; 8.71 kvars of capacitors missed. Similarly, as
the ΣRL
minimum average
value is positive, no additional compensation chokes are necessary.
You can use the compensation reserves not only for checking the capacity of existing
compensation system, but for any new compensation system dimensioning too : Install single
instrument (without any of compensation sections connected ) at the network where new
compensation system to be projected . Then perform the reserve check as described above;
set target power factor only but let all of the compensation outputs set as zero outputs and
switch the controller into the manual state. After observed period, according registered
negative minimums of the RC / RL reserves you can size the compensation system capacity.
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