ABB PQFS

16 Hardware description  Manual Power Quality Filter PQFS
Up to 8 PQFS master panels can be connected in parallel providing full redundancy to the
customer. In addition to using master panels only, PQFS units can be connected in a
master-slave arrangement.
4.3 The PQF current generator hardware
The power circuit of a PQFS unit is represented hereafter.
N
Preload
resistor
Output filter
IGBT
Inverter
Master Unit
N
AC power supply
L
L
1
2
3
4
5
6
7
8
Figure 10: Power circuit diagram of a PQFS active filter
The description of the main components is given in Table 5.
Table 5: Main components of a PQFS active filter
Item Main components
1
IGBT inverter
2 DC bus capacitors
3 PWM reactor
4
Output filter
5
Preload resistor
6
Main contactor
7 Auxiliary fuses
8 Neutral cable connection (not mandatory)