Lenze 9400 Manual - Manual (Page 329)

DC-bus operation
Basic dimensioning
Power distribution of controllers
8

329 EDS94SPP101 EN 7.1
Use the time/performance diagram to optimise the DC-bus performance of all axes for a
complete machine cycle.
Utilisation factor
Please consider the utilisation factors when determining P
DCtotal
. Reduce the power
requirements if the rated power is not fully used.
Simultaneity factor
Please consider the simultaneity factor when determining P
DCtotal
. Reduce the power
requirements if the drives do not run simultaneously or in opposite direction (braking).
Braking
After determining the brake power P
BRtotal
, ensure that the brake power can be provided
by the brake choppers and brake resistors in the DC bus.
Other conditions
The power supply unit must be able to provide the required power (arithmetic mean).
The overload requirements must be within the permissible range:
( 8.4.2)
ƒ 3-min cycle (1 min overload with 150 %/2 min recovery time with 75 %)
ƒ 5-s cycle (0.5 s overload and 4.5 s recovery time with 75 %)
For detailed information on the overload capacity, please see the Technical data.
8.5.2 Power distribution of controllers
In a DC-bus operation, the power from the AC mains is stored in the DC bus and consumed
by several controllers. Drive groups with non-synchronous power consumption, partial
load or excess energy from braking operations are suitable for establishing a DC-bus
connection.
=
=
~
~
L1, L2, L3
U, V, W
P
DC1
P
DC2
P
V
P
LN
P
aN
Power distribution
L1, L2, L3 Mains connection (3/PE AC)
P
Lr
Input mains power
P
DC1
Total DC-bus power
P
DC2
DC-bus power available for the DC bus
P
loss
Power loss
P
ar
Output power
U, V, W Motor connection