ABB ACSM1 System Manual page 23

The available energy capacity depends now on the criteria for the U
the actual DC link voltage supplied into common DC system. Selection of the
value for U depends on common DC system configuration and its
dc,lim
general requirements.
Here are the major alternatives for the U
module DC voltage limits (see also the paragraph ACSM1 DC voltage
limits).
•
Absolute maximum limit is defined according to the DC overvoltage trip
limit including some safety margin.
≤
U 840
V DC
dc ,lim
•
DC over voltage control is enabled, but not activated.
≤
U 810
V DC
dc , lim
•
DC link voltage level, where the braking choppers are not yet
activated.
≤
U 780
V DC
dc ,lim
To determine whether the energy capacity is adequate (i.e. the selected
U voltage level is not reached) the following condition must be fulfilled
dc,lim
•
W > E
dc gen
Where E is the regenerative energy to the DC link during the generating
gen
period:
=
E P dt
•
gen gen
based on the ACSM1 drive
dc,lim
23
and
dc,lim