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

2.2 T-reactor for 12 – pulse parallel configurations
DCS 600 Manual for 12 – Pulse Operation
9 8T Ã% 
!ƒ ˆ y†r ÃH 6 TU @ SÃ
D 1
The T-reactor also known as interphase transformer (
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.
Chapter 2 – Twelve–Pulse Technology
∆
!ƒˆy†rÃh…hyyryÃ
p‚svtˆ…h‡v‚
C 1
T-REACTOR

G
PRW

D
D D
0
Ã
Field
‡
‚
/
€
9 8T Ã% 
!ƒ ˆ y†r ÃT G6 W @
C 1 D 1

Figure 2/7
) ab-
Figure 2/7
II F2
2 - 5