Single Braking Chopper; Multiple Braking Choppers - ABB ACSM1 System Manual

Single braking chopper

In this case only one braking chopper of a drive module in the common DC
system is used. It is recommended to use the chopper of the drive module,
which have the highest braking power ratings. The following conditions
should be fulfilled:
<
P P
•
gen , ave
<
• P P
gen ,max
If the conditions can not be fulfilled, either a drive module with higher P
ratings can be selected (if feasible) or a multiple braking chopper
configuration can be used.

Multiple braking choppers

In case two or more braking choppers of drive modules are active in the
common DC system, the same conditions as above must still be fulfilled.
<
• P P
gen , ave
<
P P
•
gen ,max
where P ratings are now calculated from the individual ratings as follows
br
=
P P
•
br , cont br
=
• P P
br ,max br
P and P
br,cont1 br,max1
power ratings.
br , cont
br ,max
br , cont
br ,max
+ ×
0 . 8 ( P
, cont 1 br , cont 2
+ ×
0 . 7 ( P
,max 1 br ,max
are the values of the drive module with highest braking
+ +
P ...)
br , cont 3
+ +
P ...)
2 br ,max 3
25
br