Elspec EQUALIZER-ST, Руководство пользователя и инструкция по установке, Страница: 45 / 121

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www.elspec-ltd.com | December 2014 | SMX-0609-0101
User Manual | EQ-ST | V15
Average Mode: The Power Factor will be as close as possible to the programmed value, either from
below or above.
The actual kVAr will be less than that required and more than that
required by maximum half step size plus half "In/Out threshold".
Figure 47 through Figure 51 show example of a network with four different configurations. The system step
size is 100kVAr and the requirement increases from 100 kVAr to 215 kVAr, than back to 150 kVAr and remains
at 150 kVAr with minor changes due to CT inaccuracy. The calculated kVAr (amount of kVAr to connect
calculated by the control mode) is marked as

, the actual connected kVAr are marked as

and the
difference between them (compensation variation) is marked as

. The light vertical lines show the margins
between connection and disconnection of a step.
The difference between Figure 47, Figure 48 and Figure 49 is the value of the In/Out threshold. With the 50%
value there are minimal changes is the connected capacity but larger differences between the target value
and the actual. With the 5% threshold there are useless connections and disconnection at the end while the
20% works best in this example.
The difference between Figure 49, Figure 50 and Figure 51 is the Power Factor mode. In the first the connected
capacity is more or less the required, in the second it is always higher (with regards to the In/Out threshold)
while in the third it is always less.
Figure 47: PF Mode Average with 50% Threshold Example
-100
-50
0
50
100
150
200
250
300
350
Time
k
V
A
r
Calculated kVAr Connected kVAr Calc. Minus Conn. kVAr