KMB NOVAR 2600, Operating Manual

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NOVAR 2600 Operating Manual
ΔQfh
1
….... control deviation reactive power of L1-phase
* ) The outputs that have non-zero reactive power and that are not set as fixed outputs are
considered as the control outputs (including the outputs that are temporary disabled due to
OE-alarm actuation).
Then, three-phase reserves are :
Capacitive three-phase reserve reactive power :
∑
RC = RC
1
+ RC
2
+ RC
3
Inductive three-phase reserve reactive power :
∑
RL = RL
1
+ RL
2
+ RL
3
If any reserve is positive that means that there are still one or more outputs that can switched on or off
to reach target power factor in the network.
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. Switch to the general meter actual values and scroll to three-phase power values. Push the
►button until 3dQ/3RL/3RC option is selected - then window with actual three-phase
control deviation and reserve powers appears.
4. With the button switch to -icon, i.e. to average values.
5. Now clear up till now registered maximum&minimum power values : press the ►button
repetitive until Clear option is selected, then at the confirmation window press the  button.
6. 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.
Fig. 4.20 : Compensation Reserves - Fig. 4.21 : Compensation Reserves -
Sufficient Insufficient Capacitive Reserve
For compensation reactive power capacity assessment, registered minimum values of both reserves
are decisive. On example on Fig. 4.20, 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 next figure shows, reactive power of
magnitude that the controller could not compensate appeared sometimes in the network during the
testing period. As
the 3RC
minimum average value is negative, the capacity of compensation
capacitors is not sufficient ; 8.71 kvars of capacitors missed. Similarly, as the 3RL minimum average
value is positive, no additional compensation chokes are necessary.
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