62 Electrical design and installation
Manual Power Quality Filter PQFM
6.10.2 CT locations for the case of global compensation – one feeding
transformer
This case handles the most frequent configuration: one transformer feeds several non-
linear loads. The active filter is installed at a central position and filters the harmonic
currents of all the loads. This configuration is shown in
.
PQF
LOAD LOAD LOAD
Supply
Figure 39: CT connections for the case of global compensation – one feeding transformer
The connection method for the three CTs to the filter is described in
Section 6.10.1
.
6.10.3 CT locations for the case of individual compensation – one feeding
transformer
Instead of installing one active filter in a central position, it is also possible to connect
the active filter and its CTs so that it compensates one particular load only. In the
example hereafter, the active filter PQF is connected to compensate load 1 only. It does
not see load 2.
LOAD 2
LOAD 1
PQF
Figure 40: CT connections for the case of individual compensation – one
feeding transformer
The connection method for the three CTs to the active filter is described in
Section 6.10.1
.