Technical data
June 2008
40-214
For more information visit: www.eaton.com CA08102001E
Adjustable Frequency Drives
40
CFX9000
Enclosed Drives
2. Passive Filters
Tuned harmonic filters involve the series connection of an
inductor with the shunt connection of an inductor and capac-
itor to form a low impedance path to ground for a specific
range of frequencies. This path presents an alternative to the
flow of harmonic currents back into the utility source.
Figure 40-119. CFX9000 Drive with Integrated Passive Filter
Figure 40-120. 100 hp CFX9000 480V Drive with Integrated Passive Filter
Table 40-315. 100 hp CFX9000 480V Drive with Integrated Passive Filter
Advantages
■ Low cost for smaller horsepower applications
■ More effective harmonic attenuation than 12-pulse drives
■ Provides increased input protection for AFD from line
transients
Disadvantages
■ Capacitors age over time, unlike magnetics
■ Not as effective as 18-pulse drives
■ Challenging to retrofit with bypass applications
3-Phase
Input
AC Input
Reactor
L1A
L2A
L3A
1
2
3
Output Transistors
IGBT Section
Dynamic Braking
Tra nsistor
6-Pulse Diode
Bridge Rectifier
Converter Section
Shunt
Fusing
Tuned
Shunt
Reactor
Tuned
Harmonic
Capacitor
Inverter Section
(
–
) DC
(
+
) DC
Bus
Capacitors
AC
Motor
Passive Filter
Current Harmonics
I
1
= 100% I
11
= .24% I
19
= .50%
I
5
= 3.76% I
13
= 1.1% I
23
= .55%
I
7
= 1.65% I
17
= .80% I
25
= 0.8%
Power = 74.6 kW
H
c
= 8.6 Amps
200
Current
Amps
100
0
-100
-200
Time