Siemens SINAMICS V10 - Compound Braking Current; Configuration of VDC Controller

Par. No. Name Range Default Unit
P1236 Compound braking current 0 - 250 0 %
Defines DC level superimposed on AC waveform after exceeding DC-link voltage threshold of compound
braking. The value is entered in [%] relative to rated motor current (P0305).
The Compound Brake is an overlay of the DC brake function with regenerative braking (effeteve braking at
the ramp) after OFF1 or OFF3. This enables braking with controlled motor frequency and a minimum of energy
returned to the motor. Through optimization of the ramp-down time and the compound braking an effective
braking without additional HW components is possible.
f
i
t
t
f_act
f_set
P1236 = 0
Without Compound braking
u
t
f
i
t
t
f_act
f_set
P1236 > 0
With Compound braking
t
DC-link
u
DC-link
U
DC_Comp
Value:
P1236 = 0 Compound braking is disaled
P1236 = 1...250 Level of DC braking current defined as a [%] of rated motor current (P0305).
Dependency:
Compound braking depends on the DC link voltage only. It will be active with OFF1/OFF3 and at regenerating
conditions.
It is disabled when:
● DC braking is active
● Flying start is active
Notice:
Increasing the value will generally improve braking performance; however, if you set the value too high, an
overcurrent trip may result. If used with dynamic braking enabled as well compound braking will take priority.
If used with the Vdc max. controller enabled the drive behavior while braking may be worsened particularly
with high values of compound braking.
P1240 Configuration of Vdc controller 0 - 1 1 --
Enables/disables Vdc controller.
The Vdc controller dynamically controls the DC link voltage to prevent trips on high inertia systems.
Possible settings:
0 Vdc controller disabled
1 Vdc-max controller enabled
Parameter list
SINAMICS V10
100 Operating Instructions, 08/2011, A5E03453178 (this is not an order number)