Lenze 9400 Manual - Manual (Page 273)

Regenerative power supply modules
Rated data (devices for 400/500V mains)
Regenerative feedback with brake chopper
7

273 EDS94SPP101-7.1
Example: Deceleration with power recovery and brake chopper
The following diagram shows the time characteristics of the speed and the corresponding
power. Regenerative powers (into the DC bus connection) are shown as negative values.
This energy must be dissipated by the regenerative power supply module to the supply
system. In the example, the regenerative power is that high that a brake chopper is
required.
P
BRon
P
Mmax
P + P
Mmax BRmax
t
E
BR
E
Mgen
t
n 
0
P
gen
P
mot
P
94SSPVR050 (E)
Fig. 7-2 Power regeneration - energy characteristics for deceleration in the limit range
P
Power (general)
t Time axis
n Speed
P
mot
Power in motor mode
P
gen
Regenerative power
P
Mgen
Regenerative power into mains
P
Mmax
max. regenerative power into mains (= cycle 1, P
DC
)
P
BR
Power loss via brake resistor
P
BRmax
max. power loss via brake resistor
P
Bron
Switch-on position of brake chopper
E
Mgen
Regenerative energy into mains
E
BR
Energy loss via brake resistor
c Braking
The hatched area E
Mgen
shows the energy dissipated to the supply system. The hatched
area E
Br
shows the power loss in the brake resistor. With cyclic processes, the power loss
must be referred to the cycle time t (mean time between two deceleration processes) to
obtain the mean power loss (=continuous power) of the brake resistor: P
BrAV
= E
Br
/ t. The
mean power loss is important for the dimensioning of the brake resistor. Mains voltage
tolerances and resistance value changes due to the tolerance and the temperature rise
must be considered.
Type
U
r
[V]
P
DC (100 %)
[kW]
P
Mmax
[kW]
P
BRmax
[kW]
P
Mmax
+ P
BRmax
[kW]
P
Bron
[kW]
U
BRmax
[V]
E94ARNE0134
230
4.3 12.9 6.6 19.5 9.9
345
E94ARNE0244 7.8 23.3 13.2 36.5 17.9
E94ARNE0134
400
7.5 22.4 12.7 35.1 17.2
586
E94ARNE0244 13.5 40.5 19.1 59.6 31.0
E94ARNE0134
500
9.3 28.0 19.6 47.6 19.6
727
E94ARNE0244 16.9 50.6 29.4 80.0 35.4