ABB DCS 600 MultiDrive Series - T-Reactor for 12 - Pulse Parallel Configurations

Chapter 2 – Twelve–Pulse Technology
DCS 600 Manual for 12 – Pulse Operation II F2 2 - 5
2.2 T-reactor for 12 – pulse parallel configurations
SXOVH0 $67 (5 SXOVH6 /$ 9(
C1D1 C1 D1
0
∆
<
T-REACTOR
SXOVHSDUDOOHO
FRQILJXUDWLRQ
/
P
R
W

,
PRW
,

,

/

Field
'&6 '&6
Figure 2/7
The T-reactor also known as interphase transformer (Figure 2/7) ab-
sorbes the instantaneous difference between the output voltages of
both converters (master and slave). This voltage difference is an AC
voltage with a maximum amplitude of 50 % of the peak value of the AC
input voltage of the converters.
The almost rectangular form of this voltage results in a nearly triangu-
lar AC current in the T-reactor.This magnetising current is superposed
by the difference of the DC current produced by both converters. How-
ever this difference is monitored by the master converter and the cur-
rent controllers of the master-slave drive configuration is able to limit it
to below 2 %.
T-reactors delivered from ABB Automation Products GmbH, Lampert-
heim have enough margin in this case, because they are designed for
10 % saturation current.
T-reactors provide a typical 12 – pulse voltage ripple characteristic to
the motor (higher frequency and lower amplitude) resulting in a current
which has four times less ripple than in a standard 6 – pulse configura-
tion.